New Grease Pencil object for 2D animation

This commit merge the full development done in greasepencil-object branch and include mainly the following features.

- New grease pencil object.
- New drawing engine.
- New grease pencil modes Draw/Sculpt/Edit and Weight Paint.
- New brushes for grease pencil.
- New modifiers for grease pencil.
- New shaders FX.
- New material system (replace old palettes and colors).
- Split of annotations (old grease pencil) and new grease pencil object.
- UI adapted to blender 2.8.

You can get more info here:

https://code.blender.org/2017/12/drawing-2d-animation-in-blender-2-8/
https://code.blender.org/2018/07/grease-pencil-status-update/

This is the result of nearly two years of development and I want thanks firstly the other members of the grease pencil team: Daniel M. Lara, Matias Mendiola and Joshua Leung for their support, ideas and to keep working in the project all the time, without them this project had been impossible.

Also, I want thanks other Blender developers for their help, advices and to be there always to help me, and specially to Clément Foucault, Dalai Felinto, Pablo Vázquez and Campbell Barton.

28 files changed, 3146 insertions, 637 deletions

diff --git a/source/blender/blenkernel/BKE_brush.h b/source/blender/blenkernel/BKE_brush.h
index eda1c51bbc2..489746cbfd9 100644
--- a/source/blender/blenkernel/BKE_brush.h
+++ b/source/blender/blenkernel/BKE_brush.h
@@ -28,11 +28,14 @@
  */
 
 enum eCurveMappingPreset;
+struct bContext;
 struct Brush;
+struct Paint;
 struct ImBuf;
 struct ImagePool;
 struct Main;
 struct Scene;
+struct ToolSettings;
 struct UnifiedPaintSettings;
 // enum eCurveMappingPreset;
 
@@ -45,14 +48,17 @@ void BKE_brush_system_exit(void);
 /* datablock functions */
 void BKE_brush_init(struct Brush *brush);
 struct Brush *BKE_brush_add(struct Main *bmain, const char *name, const eObjectMode ob_mode);
+struct Brush *BKE_brush_add_gpencil(struct Main *bmain, struct ToolSettings *ts, const char *name);
 struct Brush *BKE_brush_first_search(struct Main *bmain, const eObjectMode ob_mode);
 void BKE_brush_copy_data(struct Main *bmain, struct Brush *brush_dst, const struct Brush *brush_src, const int flag);
 struct Brush *BKE_brush_copy(struct Main *bmain, const struct Brush *brush);
 void BKE_brush_make_local(struct Main *bmain, struct Brush *brush, const bool lib_local);
-void BKE_brush_unlink(struct Main *bmain, struct Brush *brush);
 void BKE_brush_free(struct Brush *brush);
 
 void BKE_brush_sculpt_reset(struct Brush *brush);
+void BKE_brush_gpencil_presets(struct bContext *C);
+struct Brush *BKE_brush_getactive_gpencil(struct ToolSettings *ts);
+struct Paint *BKE_brush_get_gpencil_paint(struct ToolSettings *ts);
 
 /* image icon function */
 struct ImBuf *get_brush_icon(struct Brush *brush);
diff --git a/source/blender/blenkernel/BKE_context.h b/source/blender/blenkernel/BKE_context.h
index 9f57859d318..28dcf9cb127 100644
--- a/source/blender/blenkernel/BKE_context.h
+++ b/source/blender/blenkernel/BKE_context.h
@@ -65,9 +65,7 @@ struct bPoseChannel;
 struct bGPdata;
 struct bGPDlayer;
 struct bGPDframe;
-struct bGPDpalette;
-struct bGPDpalettecolor;
-struct bGPDbrush;
+struct Brush;
 struct wmWindow;
 struct wmWindowManager;
 struct RenderEngineType;
@@ -120,6 +118,10 @@ enum {
 	CTX_MODE_PAINT_TEXTURE,
 	CTX_MODE_PARTICLE,
 	CTX_MODE_OBJECT,
+	CTX_MODE_GPENCIL_PAINT,
+	CTX_MODE_GPENCIL_EDIT,
+	CTX_MODE_GPENCIL_SCULPT,
+	CTX_MODE_GPENCIL_WEIGHT,
 	CTX_MODE_NUM /* must be last */
 };
 
@@ -313,9 +315,7 @@ int CTX_data_visible_pose_bones(const bContext *C, ListBase *list);
 struct bGPdata *CTX_data_gpencil_data(const bContext *C);
 struct bGPDlayer *CTX_data_active_gpencil_layer(const bContext *C);
 struct bGPDframe *CTX_data_active_gpencil_frame(const bContext *C);
-struct bGPDpalette *CTX_data_active_gpencil_palette(const bContext *C);
-struct bGPDpalettecolor *CTX_data_active_gpencil_palettecolor(const bContext *C);
-struct bGPDbrush *CTX_data_active_gpencil_brush(const bContext *C);
+struct Brush *CTX_data_active_gpencil_brush(const bContext *C);
 int CTX_data_visible_gpencil_layers(const bContext *C, ListBase *list);
 int CTX_data_editable_gpencil_layers(const bContext *C, ListBase *list);
 int CTX_data_editable_gpencil_strokes(const bContext *C, ListBase *list);
diff --git a/source/blender/blenkernel/BKE_gpencil.h b/source/blender/blenkernel/BKE_gpencil.h
index 3a951b7860d..887a7f4f67b 100644
--- a/source/blender/blenkernel/BKE_gpencil.h
+++ b/source/blender/blenkernel/BKE_gpencil.h
@@ -31,25 +31,45 @@
  *  \author Joshua Leung
  */
 
+struct CurveMapping;
+struct Depsgraph;
+struct GpencilModifierData;
 struct ToolSettings;
 struct ListBase;
 struct bGPdata;
 struct bGPDlayer;
 struct bGPDframe;
+struct bGPDspoint;
 struct bGPDstroke;
+struct Material;
 struct bGPDpalette;
 struct bGPDpalettecolor;
 struct Main;
+struct BoundBox;
+struct Brush;
+struct Object;
+struct bDeformGroup;
+struct SimplifyGpencilModifierData;
+struct InstanceGpencilModifierData;
+struct LatticeGpencilModifierData;
+
+struct MDeformVert;
+struct MDeformWeight;
 
 /* ------------ Grease-Pencil API ------------------ */
 
+void BKE_gpencil_free_point_weights(struct MDeformVert *dvert);
+void BKE_gpencil_free_stroke_weights(struct bGPDstroke *gps);
 void BKE_gpencil_free_stroke(struct bGPDstroke *gps);
 bool BKE_gpencil_free_strokes(struct bGPDframe *gpf);
 void BKE_gpencil_free_frames(struct bGPDlayer *gpl);
 void BKE_gpencil_free_layers(struct ListBase *list);
-void BKE_gpencil_free_brushes(struct ListBase *list);
-void BKE_gpencil_free_palettes(struct ListBase *list);
-void BKE_gpencil_free(struct bGPdata *gpd, bool free_palettes);
+bool BKE_gpencil_free_frame_runtime_data(struct bGPDframe *derived_gpf);
+void BKE_gpencil_free_derived_frames(struct bGPdata *gpd);
+void BKE_gpencil_free(struct bGPdata *gpd, bool free_all);
+
+void BKE_gpencil_batch_cache_dirty(struct bGPdata *gpd);
+void BKE_gpencil_batch_cache_free(struct bGPdata *gpd);
 
 void BKE_gpencil_stroke_sync_selection(struct bGPDstroke *gps);
 
@@ -60,21 +80,36 @@ struct bGPdata   *BKE_gpencil_data_addnew(struct Main *bmain, const char name[])
 
 struct bGPDframe *BKE_gpencil_frame_duplicate(const struct bGPDframe *gpf_src);
 struct bGPDlayer *BKE_gpencil_layer_duplicate(const struct bGPDlayer *gpl_src);
+void BKE_gpencil_frame_copy_strokes(struct bGPDframe *gpf_src, struct bGPDframe *gpf_dst);
+struct bGPDstroke *BKE_gpencil_stroke_duplicate(struct bGPDstroke *gps_src);
+
 void BKE_gpencil_copy_data(struct Main *bmain, struct bGPdata *gpd_dst, const struct bGPdata *gpd_src, const int flag);
+struct bGPdata   *BKE_gpencil_copy(struct Main *bmain, const struct bGPdata *gpd);
 struct bGPdata   *BKE_gpencil_data_duplicate(struct Main *bmain, const struct bGPdata *gpd, bool internal_copy);
 
 void BKE_gpencil_make_local(struct Main *bmain, struct bGPdata *gpd, const bool lib_local);
 
 void BKE_gpencil_frame_delete_laststroke(struct bGPDlayer *gpl, struct bGPDframe *gpf);
 
-struct bGPDpalette *BKE_gpencil_palette_addnew(struct bGPdata *gpd, const char *name, bool setactive);
-struct bGPDpalette *BKE_gpencil_palette_duplicate(const struct bGPDpalette *palette_src);
-struct bGPDpalettecolor *BKE_gpencil_palettecolor_addnew(struct bGPDpalette *palette, const char *name, bool setactive);
+/* materials */
+void BKE_gpencil_material_index_remove(struct bGPdata *gpd, int index);
+void BKE_gpencil_material_remap(struct bGPdata *gpd, const unsigned int *remap, unsigned int remap_len);
 
-struct bGPDbrush *BKE_gpencil_brush_addnew(struct ToolSettings *ts, const char *name, bool setactive);
-struct bGPDbrush *BKE_gpencil_brush_duplicate(const struct bGPDbrush *brush_src);
-void BKE_gpencil_brush_init_presets(struct ToolSettings *ts);
+/* statistics functions */
+void BKE_gpencil_stats_update(struct bGPdata *gpd);
 
+/* Utilities for creating and populating GP strokes */
+/* - Number of values defining each point in the built-in data
+ *   buffers for primitives (e.g. 2D Monkey)
+ */
+#define GP_PRIM_DATABUF_SIZE  5
+
+void BKE_gpencil_stroke_add_points(
+        struct bGPDstroke *gps,
+        const float *array, const int totpoints,
+        const float mat[4][4]);
+
+struct bGPDstroke *BKE_gpencil_add_stroke(struct bGPDframe *gpf, int mat_idx, int totpoints, short thickness);
 
 /* Stroke and Fill - Alpha Visibility Threshold */
 #define GPENCIL_ALPHA_OPACITY_THRESH 0.001f
@@ -103,20 +138,40 @@ struct bGPDlayer *BKE_gpencil_layer_getactive(struct bGPdata *gpd);
 void BKE_gpencil_layer_setactive(struct bGPdata *gpd, struct bGPDlayer *active);
 void BKE_gpencil_layer_delete(struct bGPdata *gpd, struct bGPDlayer *gpl);
 
-struct bGPDbrush *BKE_gpencil_brush_getactive(struct ToolSettings *ts);
-void BKE_gpencil_brush_setactive(struct ToolSettings *ts, struct bGPDbrush *active);
-void BKE_gpencil_brush_delete(struct ToolSettings *ts, struct bGPDbrush *brush);
-
-struct bGPDpalette *BKE_gpencil_palette_getactive(struct bGPdata *gpd);
-void BKE_gpencil_palette_setactive(struct bGPdata *gpd, struct bGPDpalette *active);
-void BKE_gpencil_palette_delete(struct bGPdata *gpd, struct bGPDpalette *palette);
-void BKE_gpencil_palette_change_strokes(struct bGPdata *gpd);
-
-struct bGPDpalettecolor *BKE_gpencil_palettecolor_getactive(struct bGPDpalette *palette);
-void BKE_gpencil_palettecolor_setactive(struct bGPDpalette *palette, struct bGPDpalettecolor *active);
-void BKE_gpencil_palettecolor_delete(struct bGPDpalette *palette, struct bGPDpalettecolor *palcolor);
-struct bGPDpalettecolor *BKE_gpencil_palettecolor_getbyname(struct bGPDpalette *palette, char *name);
-void BKE_gpencil_palettecolor_changename(struct bGPdata *gpd, char *oldname, const char *newname);
-void BKE_gpencil_palettecolor_delete_strokes(struct bGPdata *gpd, char *name);
+struct Material *BKE_gpencil_get_material_from_brush(struct Brush *brush);
+struct Material *BKE_gpencil_material_ensure(struct Main *bmain, struct Object *ob);
+
+/* object boundbox */
+bool BKE_gpencil_stroke_minmax(
+        const struct bGPDstroke *gps, const bool use_select,
+        float r_min[3], float r_max[3]);
+
+struct BoundBox *BKE_gpencil_boundbox_get(struct Object *ob);
+void BKE_gpencil_centroid_3D(struct bGPdata *gpd, float r_centroid[3]);
+
+/* vertex groups */
+float BKE_gpencil_vgroup_use_index(struct MDeformVert *dvert, int index);
+void BKE_gpencil_vgroup_remove(struct Object *ob, struct bDeformGroup *defgroup);
+struct MDeformWeight *BKE_gpencil_vgroup_add_point_weight(struct MDeformVert *dvert, int index, float weight);
+bool BKE_gpencil_vgroup_remove_point_weight(struct MDeformVert *dvert, int index);
+void BKE_gpencil_stroke_weights_duplicate(struct bGPDstroke *gps_src, struct bGPDstroke *gps_dst);
+
+/* GPencil geometry evaluation */
+void BKE_gpencil_eval_geometry(struct Depsgraph *depsgraph, struct bGPdata *gpd);
+
+/* stroke geometry utilities */
+void BKE_gpencil_stroke_normal(const struct bGPDstroke *gps, float r_normal[3]);
+void BKE_gpencil_simplify_stroke(struct bGPDstroke *gps, float factor);
+void BKE_gpencil_simplify_fixed(struct bGPDstroke *gps);
+
+void BKE_gpencil_transform(struct bGPdata *gpd, float mat[4][4]);
+
+bool BKE_gpencil_smooth_stroke(struct bGPDstroke *gps, int i, float inf);
+bool BKE_gpencil_smooth_stroke_strength(struct bGPDstroke *gps, int point_index, float influence);
+bool BKE_gpencil_smooth_stroke_thickness(struct bGPDstroke *gps, int point_index, float influence);
+bool BKE_gpencil_smooth_stroke_uv(struct bGPDstroke *gps, int point_index, float influence);
+
+void BKE_gpencil_get_range_selected(struct bGPDlayer *gpl, int *r_initframe, int *r_endframe);
+float BKE_gpencil_multiframe_falloff_calc(struct bGPDframe *gpf, int actnum, int f_init, int f_end, struct CurveMapping *cur_falloff);
 
 #endif /*  __BKE_GPENCIL_H__ */
diff --git a/source/blender/blenkernel/BKE_gpencil_modifier.h b/source/blender/blenkernel/BKE_gpencil_modifier.h
new file mode 100644
index 00000000000..cd6b6540012
--- /dev/null
+++ b/source/blender/blenkernel/BKE_gpencil_modifier.h
@@ -0,0 +1,256 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is: all of this file.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+#ifndef __BKE_GPENCIL_MODIFIER_H__
+#define __BKE_GPENCIL_MODIFIER_H__
+
+/** \file BKE_greasepencil_modifier.h
+ *  \ingroup bke
+ */
+
+#include "DNA_gpencil_modifier_types.h"     /* needed for all enum typdefs */
+#include "BLI_compiler_attrs.h"
+#include "BKE_customdata.h"
+
+struct ID;
+struct Depsgraph;
+struct DerivedMesh;
+struct bContext; /* NOTE: bakeModifier() - called from UI - needs to create new datablocks, hence the need for this */
+struct Mesh;
+struct Object;
+struct Scene;
+struct ViewLayer;
+struct ListBase;
+struct bArmature;
+struct Main;
+struct GpencilModifierData;
+struct BMEditMesh;
+struct DepsNodeHandle;
+struct bGPDlayer;
+struct bGPDframe;
+struct bGPDstroke;
+struct ModifierUpdateDepsgraphContext;
+
+#define GPENCIL_MODIFIER_ACTIVE(_md, _is_render) (((_md->mode & eGpencilModifierMode_Realtime) && (_is_render == false)) || \
+												  ((_md->mode & eGpencilModifierMode_Render) && (_is_render == true)))
+#define GPENCIL_MODIFIER_EDIT(_md, _is_edit) (((_md->mode & eGpencilModifierMode_Editmode) == 0) && (_is_edit))
+
+typedef enum {
+	/* Should not be used, only for None modifier type */
+	eGpencilModifierTypeType_None,
+
+	/* grease pencil modifiers */
+	eGpencilModifierTypeType_Gpencil,
+}  GpencilModifierTypeType;
+
+typedef enum {
+	eGpencilModifierTypeFlag_SupportsMapping = (1 << 0),
+	eGpencilModifierTypeFlag_SupportsEditmode = (1 << 1),
+
+	/* For modifiers that support editmode this determines if the
+	* modifier should be enabled by default in editmode. This should
+	* only be used by modifiers that are relatively speedy and
+	* also generally used in editmode, otherwise let the user enable
+	* it by hand.
+	*/
+	eGpencilModifierTypeFlag_EnableInEditmode = (1 << 2),
+
+	/* For modifiers that require original data and so cannot
+	* be placed after any non-deformative modifier.
+	*/
+	eGpencilModifierTypeFlag_RequiresOriginalData = (1 << 3),
+
+	/* max one per type */
+	eGpencilModifierTypeFlag_Single = (1 << 4),
+
+	/* can't be added manually by user */
+	eGpencilModifierTypeFlag_NoUserAdd = (1 << 5),
+} GpencilModifierTypeFlag;
+
+/* IMPORTANT! Keep ObjectWalkFunc and IDWalkFunc signatures compatible. */
+typedef void(*GreasePencilObjectWalkFunc)(void *userData, struct Object *ob, struct Object **obpoin, int cb_flag);
+typedef void(*GreasePencilIDWalkFunc)(void *userData, struct Object *ob, struct ID **idpoin, int cb_flag);
+typedef void(*GreasePencilTexWalkFunc)(void *userData, struct Object *ob, struct GpencilModifierData *md, const char *propname);
+
+typedef struct GpencilModifierTypeInfo {
+	/* The user visible name for this modifier */
+	char name[32];
+
+	/* The DNA struct name for the modifier data type, used to
+	 * write the DNA data out.
+	 */
+	char struct_name[32];
+
+	/* The size of the modifier data type, used by allocation. */
+	int struct_size;
+
+	GpencilModifierType type;
+	GpencilModifierTypeFlag flags;
+
+
+	/********************* Non-optional functions *********************/
+
+	/* Copy instance data for this modifier type. Should copy all user
+	 * level settings to the target modifier.
+	 */
+	void (*copyData)(const struct GpencilModifierData *md, struct GpencilModifierData *target);
+
+	/* Callback for GP "stroke" modifiers that operate on the
+	 * shape and parameters of the provided strokes (e.g. Thickness, Noise, etc.)
+	 *
+	 * The gpl parameter contains the GP layer that the strokes come from.
+	 * While access is provided to this data, you should not directly access
+	 * the gpl->frames data from the modifier. Instead, use the gpf parameter
+	 * instead.
+	 *
+	 * The gps parameter contains the GP stroke to operate on. This is usually a copy
+	 * of the original (unmodified and saved to files) stroke data.
+	 */
+	void (*deformStroke)(struct GpencilModifierData *md, struct Depsgraph *depsgraph,
+	                     struct Object *ob, struct bGPDlayer *gpl, struct bGPDstroke *gps);
+
+	/* Callback for GP "geometry" modifiers that create extra geometry
+	 * in the frame (e.g. Array)
+	 *
+	 * The gpf parameter contains the GP frame/strokes to operate on. This is
+	 * usually a copy of the original (unmodified and saved to files) stroke data.
+	 * Modifiers should only add any generated strokes to this frame (and not one accessed
+	 * via the gpl parameter).
+	 *
+	 * The modifier_index parameter indicates where the modifier is
+	 * in the modifier stack in relation to other modifiers.
+	 */
+	void (*generateStrokes)(struct GpencilModifierData *md, struct Depsgraph *depsgraph,
+	                        struct Object *ob, struct bGPDlayer *gpl, struct bGPDframe *gpf);
+
+	/* Bake-down GP modifier's effects into the GP datablock.
+	 *
+	 * This gets called when the user clicks the "Apply" button in the UI.
+	 * As such, this callback needs to go through all layers/frames in the
+	 * datablock, mutating the geometry and/or creating new datablocks/objects
+	 */
+	void (*bakeModifier)(struct Main *bmain, struct Depsgraph *depsgraph,
+                           struct GpencilModifierData *md, struct Object *ob);
+
+	/********************* Optional functions *********************/
+
+	/* Initialize new instance data for this modifier type, this function
+	 * should set modifier variables to their default values.
+	 *
+	 * This function is optional.
+	 */
+	void (*initData)(struct GpencilModifierData *md);
+
+	/* Free internal modifier data variables, this function should
+	 * not free the md variable itself.
+	 *
+	 * This function is optional.
+	 */
+	void (*freeData)(struct GpencilModifierData *md);
+
+	/* Return a boolean value indicating if this modifier is able to be
+	 * calculated based on the modifier data. This is *not* regarding the
+	 * md->flag, that is tested by the system, this is just if the data
+	 * validates (for example, a lattice will return false if the lattice
+	 * object is not defined).
+	 *
+	 * This function is optional (assumes never disabled if not present).
+	 */
+	bool (*isDisabled)(struct GpencilModifierData *md, int userRenderParams);
+
+	/* Add the appropriate relations to the dependency graph.
+	 *
+	 * This function is optional.
+	 */
+	void (*updateDepsgraph)(struct GpencilModifierData *md,
+	                        const struct ModifierUpdateDepsgraphContext *ctx);
+
+	/* Should return true if the modifier needs to be recalculated on time
+	 * changes.
+	 *
+	 * This function is optional (assumes false if not present).
+	 */
+	bool (*dependsOnTime)(struct GpencilModifierData *md);
+
+
+	/* Should call the given walk function on with a pointer to each Object
+	 * pointer that the modifier data stores. This is used for linking on file
+	 * load and for unlinking objects or forwarding object references.
+	 *
+	 * This function is optional.
+	 */
+	void (*foreachObjectLink)(struct GpencilModifierData *md, struct Object *ob,
+	                          GreasePencilObjectWalkFunc walk, void *userData);
+
+	/* Should call the given walk function with a pointer to each ID
+	 * pointer (i.e. each datablock pointer) that the modifier data
+	 * stores. This is used for linking on file load and for
+	 * unlinking datablocks or forwarding datablock references.
+	 *
+	 * This function is optional. If it is not present, foreachObjectLink
+	 * will be used.
+	 */
+	void (*foreachIDLink)(struct GpencilModifierData *md, struct Object *ob,
+	                      GreasePencilIDWalkFunc walk, void *userData);
+
+	/* Should call the given walk function for each texture that the
+	 * modifier data stores. This is used for finding all textures in
+	 * the context for the UI.
+	 *
+	 * This function is optional. If it is not present, it will be
+	 * assumed the modifier has no textures.
+	 */
+	void (*foreachTexLink)(struct GpencilModifierData *md, struct Object *ob,
+	                       GreasePencilTexWalkFunc walk, void *userData);
+} GpencilModifierTypeInfo;
+
+void BKE_gpencil_instance_modifier_instance_tfm(struct InstanceGpencilModifierData *mmd, const int elem_idx[3], float r_mat[4][4]);
+
+/* Initialize modifier's global data (type info and some common global storages). */
+void BKE_gpencil_modifier_init(void);
+
+const GpencilModifierTypeInfo *BKE_gpencil_modifierType_getInfo(GpencilModifierType type);
+struct GpencilModifierData  *BKE_gpencil_modifier_new(int type);
+void BKE_gpencil_modifier_free_ex(struct GpencilModifierData *md, const int flag);
+void BKE_gpencil_modifier_free(struct GpencilModifierData *md);
+bool BKE_gpencil_modifier_unique_name(struct ListBase *modifiers, struct GpencilModifierData *gmd);
+bool BKE_gpencil_modifier_dependsOnTime(struct GpencilModifierData *md);
+struct GpencilModifierData *BKE_gpencil_modifiers_findByType(struct Object *ob, GpencilModifierType type);
+struct GpencilModifierData *BKE_gpencil_modifiers_findByName(struct Object *ob, const char *name);
+void BKE_gpencil_modifier_copyData_generic(const struct GpencilModifierData *md_src, struct GpencilModifierData *md_dst);
+void BKE_gpencil_modifier_copyData(struct GpencilModifierData *md, struct GpencilModifierData *target);
+void BKE_gpencil_modifier_copyData_ex(struct GpencilModifierData *md, struct GpencilModifierData *target, const int flag);
+void BKE_gpencil_modifiers_foreachIDLink(struct Object *ob, GreasePencilIDWalkFunc walk, void *userData);
+void BKE_gpencil_modifiers_foreachTexLink(struct Object *ob, GreasePencilTexWalkFunc walk, void *userData);
+
+bool BKE_gpencil_has_geometry_modifiers(struct Object *ob);
+
+void BKE_gpencil_stroke_modifiers(
+	struct Depsgraph *depsgraph, struct Object *ob,
+	struct bGPDlayer *gpl, struct bGPDframe *gpf, struct bGPDstroke *gps, bool is_render);
+void BKE_gpencil_geometry_modifiers(
+	struct Depsgraph *depsgraph, struct Object *ob,
+	struct bGPDlayer *gpl, struct bGPDframe *gpf, bool is_render);
+
+void BKE_gpencil_lattice_init(struct Object *ob);
+void BKE_gpencil_lattice_clear(struct Object *ob);
+
+#endif /* __BKE_GPENCIL_MODIFIER_H__ */
diff --git a/source/blender/blenkernel/BKE_icons.h b/source/blender/blenkernel/BKE_icons.h
index 22897d2ea80..7a5262e0a14 100644
--- a/source/blender/blenkernel/BKE_icons.h
+++ b/source/blender/blenkernel/BKE_icons.h
@@ -43,7 +43,10 @@ enum {
 	ICON_DATA_PREVIEW,
 	/** 2D triangles: obj is #Icon_Geom */
 	ICON_DATA_GEOM,
+	/** Studiolight */
 	ICON_DATA_STUDIOLIGHT,
+	/** GPencil Layer color preview (annotations): obj is #bGPDlayer */
+	ICON_DATA_GPLAYER,
 };
 
 struct Icon {
@@ -79,6 +82,7 @@ struct ImBuf;
 struct PreviewImage;
 struct ID;
 struct StudioLight;
+struct bGPDlayer;
 
 enum eIconSizes;
 
@@ -87,6 +91,9 @@ void BKE_icons_init(int first_dyn_id);
 /* return icon id for library object or create new icon if not found */
 int BKE_icon_id_ensure(struct ID *id);
 
+/* return icon id for Grease Pencil layer (color preview) or create new icon if not found */
+int BKE_icon_gplayer_color_ensure(struct bGPDlayer *gpl);
+
 int BKE_icon_preview_ensure(struct ID *id, struct PreviewImage *preview);
 
 /* retrieve icon for id */
diff --git a/source/blender/blenkernel/BKE_lattice.h b/source/blender/blenkernel/BKE_lattice.h
index c2ac5e98f76..67e6a32edfd 100644
--- a/source/blender/blenkernel/BKE_lattice.h
+++ b/source/blender/blenkernel/BKE_lattice.h
@@ -54,7 +54,6 @@ void BKE_lattice_free(struct Lattice *lt);
 void BKE_lattice_make_local(struct Main *bmain, struct Lattice *lt, const bool lib_local);
 void calc_lat_fudu(int flag, int res, float *r_fu, float *r_du);
 
-struct LatticeDeformData;
 struct LatticeDeformData *init_latt_deform(struct Object *oblatt, struct Object *ob) ATTR_WARN_UNUSED_RESULT;
 void calc_latt_deform(struct LatticeDeformData *lattice_deform_data, float co[3], float weight);
 void end_latt_deform(struct LatticeDeformData *lattice_deform_data);
diff --git a/source/blender/blenkernel/BKE_material.h b/source/blender/blenkernel/BKE_material.h
index c85017a2216..1ca8928c61d 100644
--- a/source/blender/blenkernel/BKE_material.h
+++ b/source/blender/blenkernel/BKE_material.h
@@ -54,11 +54,13 @@ void BKE_material_init(struct Material *ma);
 void BKE_material_remap_object(struct Object *ob, const unsigned int *remap);
 void BKE_material_remap_object_calc(struct  Object *ob_dst, struct Object *ob_src, short *remap_src_to_dst);
 struct Material *BKE_material_add(struct Main *bmain, const char *name);
+struct Material *BKE_material_add_gpencil(struct Main *bmain, const char *name);
 void BKE_material_copy_data(struct Main *bmain, struct Material *ma_dst, const struct Material *ma_src, const int flag);
 struct Material *BKE_material_copy(struct Main *bmain, const struct Material *ma);
 struct Material *BKE_material_localize(struct Material *ma);
 struct Material *give_node_material(struct Material *ma); /* returns node material or self */
 void BKE_material_make_local(struct Main *bmain, struct Material *ma, const bool lib_local);
+void BKE_material_init_gpencil_settings(struct Material *ma);
 
 /* UNUSED */
 // void automatname(struct Material *);
@@ -87,6 +89,8 @@ short BKE_object_material_slot_find_index(struct Object *ob, struct Material *ma
 bool  BKE_object_material_slot_add(struct Main *bmain, struct Object *ob);
 bool  BKE_object_material_slot_remove(struct Main *bmain, struct Object *ob);
 
+struct MaterialGPencilStyle *BKE_material_gpencil_settings_get(struct Object *ob, short act);
+
 void BKE_texpaint_slot_refresh_cache(struct Scene *scene, struct Material *ma);
 void BKE_texpaint_slots_refresh_object(struct Scene *scene, struct Object *ob);
 
diff --git a/source/blender/blenkernel/BKE_object.h b/source/blender/blenkernel/BKE_object.h
index 79e4f1d448a..7d795c25a04 100644
--- a/source/blender/blenkernel/BKE_object.h
+++ b/source/blender/blenkernel/BKE_object.h
@@ -37,8 +37,11 @@ extern "C" {
 
 struct Base;
 struct Depsgraph;
+struct GpencilModifierData;
 struct Scene;
+struct ShaderFxData;
 struct ViewLayer;
+struct ID;
 struct Object;
 struct BoundBox;
 struct View3D;
@@ -49,6 +52,7 @@ struct Mesh;
 struct RigidBodyWorld;
 struct HookModifierData;
 struct ModifierData;
+struct HookGpencilModifierData;
 
 #include "DNA_object_enums.h"
 
@@ -69,11 +73,16 @@ void BKE_object_free_derived_mesh_caches(struct Object *ob);
 void BKE_object_free_caches(struct Object *object);
 
 void BKE_object_modifier_hook_reset(struct Object *ob, struct HookModifierData *hmd);
+void BKE_object_modifier_gpencil_hook_reset(struct Object *ob, struct HookGpencilModifierData *hmd);
+bool BKE_object_modifier_gpencil_use_time(struct Object *ob, struct GpencilModifierData *md);
+
+bool BKE_object_shaderfx_use_time(struct Object *ob, struct ShaderFxData *md);
 
 bool BKE_object_support_modifier_type_check(const struct Object *ob, int modifier_type);
 
 void BKE_object_link_modifiers(struct Scene *scene, struct Object *ob_dst, const struct Object *ob_src);
 void BKE_object_free_modifiers(struct Object *ob, const int flag);
+void BKE_object_free_shaderfx(struct Object *ob, const int flag);
 
 void BKE_object_make_proxy(struct Main *bmain, struct Object *ob, struct Object *target, struct Object *gob);
 void BKE_object_copy_proxy_drivers(struct Object *ob, struct Object *target);
@@ -108,6 +117,9 @@ struct Object *BKE_object_add_from(
         struct Main *bmain, struct Scene *scene, struct ViewLayer *view_layer,
         int type, const char *name, struct Object *ob_src)
         ATTR_NONNULL(1, 2, 3, 6) ATTR_RETURNS_NONNULL;
+struct Object *BKE_object_add_for_data(
+        struct Main *bmain, struct ViewLayer *view_layer,
+        int type, const char *name, struct ID *data, bool do_id_user) ATTR_RETURNS_NONNULL;
 void *BKE_object_obdata_add_from_type(
         struct Main *bmain,
         int type, const char *name)
diff --git a/source/blender/blenkernel/BKE_paint.h b/source/blender/blenkernel/BKE_paint.h
index 6ade14b275c..c440a634c9f 100644
--- a/source/blender/blenkernel/BKE_paint.h
+++ b/source/blender/blenkernel/BKE_paint.h
@@ -77,7 +77,8 @@ typedef enum ePaintMode {
 	ePaintTextureProjective = 3,
 	ePaintTexture2D = 4,
 	ePaintSculptUV = 5,
-	ePaintInvalid = 6
+	ePaintInvalid = 6,
+	ePaintGpencil = 7
 } ePaintMode;
 
 /* overlay invalidation */
diff --git a/source/blender/blenkernel/BKE_shader_fx.h b/source/blender/blenkernel/BKE_shader_fx.h
new file mode 100644
index 00000000000..11c5983106a
--- /dev/null
+++ b/source/blender/blenkernel/BKE_shader_fx.h
@@ -0,0 +1,180 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is: all of this file.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+#ifndef __BKE_SHADER_FX_H__
+#define __BKE_SHADER_FX_H__
+
+/** \file BKE_shader_fx.h
+ *  \ingroup bke
+ */
+
+#include "DNA_shader_fx_types.h"     /* needed for all enum typdefs */
+#include "BLI_compiler_attrs.h"
+#include "BKE_customdata.h"
+
+struct ID;
+struct Depsgraph;
+struct DerivedMesh;
+struct Mesh;
+struct Object;
+struct Scene;
+struct ViewLayer;
+struct ListBase;
+struct bArmature;
+struct Main;
+struct ShaderFxData;
+struct DepsNodeHandle;
+struct bGPDlayer;
+struct bGPDframe;
+struct bGPDstroke;
+struct ModifierUpdateDepsgraphContext;
+
+#define SHADER_FX_ACTIVE(_fx, _is_render) (((_fx->mode & eShaderFxMode_Realtime) && (_is_render == false)) || \
+												  ((_fx->mode & eShaderFxMode_Render) && (_is_render == true))) 
+#define SHADER_FX_EDIT(_fx, _is_edit) (((_fx->mode & eShaderFxMode_Editmode) == 0) && (_is_edit))
+
+typedef enum {
+	/* Should not be used, only for None type */
+	eShaderFxType_NoneType,
+
+	/* grease pencil effects */
+	eShaderFxType_GpencilType,
+}  ShaderFxTypeType;
+
+typedef enum {
+	eShaderFxTypeFlag_SupportsEditmode = (1 << 0),
+
+	/* For effects that support editmode this determines if the
+	* effect should be enabled by default in editmode. 
+	*/
+	eShaderFxTypeFlag_EnableInEditmode = (1 << 2),
+
+	/* max one per type */
+	eShaderFxTypeFlag_Single = (1 << 4),
+
+	/* can't be added manually by user */
+	eShaderFxTypeFlag_NoUserAdd = (1 << 5),
+} ShaderFxTypeFlag;
+
+/* IMPORTANT! Keep ObjectWalkFunc and IDWalkFunc signatures compatible. */
+typedef void(*ShaderFxObjectWalkFunc)(void *userData, struct Object *ob, struct Object **obpoin, int cb_flag);
+typedef void(*ShaderFxIDWalkFunc)(void *userData, struct Object *ob, struct ID **idpoin, int cb_flag);
+typedef void(*ShaderFxTexWalkFunc)(void *userData, struct Object *ob, struct ShaderFxData *fx, const char *propname);
+
+typedef struct ShaderFxTypeInfo {
+	/* The user visible name for this effect */
+	char name[32];
+
+	/* The DNA struct name for the effect data type, used to
+	 * write the DNA data out.
+	 */
+	char struct_name[32];
+
+	/* The size of the effect data type, used by allocation. */
+	int struct_size;
+
+	ShaderFxTypeType type;
+	ShaderFxTypeFlag flags;
+
+	/* Copy instance data for this effect type. Should copy all user
+	* level settings to the target effect.
+	*/
+	void(*copyData)(const struct ShaderFxData *fx, struct ShaderFxData *target);
+
+	/* Initialize new instance data for this effect type, this function
+	 * should set effect variables to their default values.
+	 * 
+	 * This function is optional.
+	 */
+	void (*initData)(struct ShaderFxData *fx);
+
+	/* Free internal effect data variables, this function should
+	 * not free the fx variable itself.
+	 *
+	 * This function is optional.
+	 */
+	void (*freeData)(struct ShaderFxData *fx);
+
+	/* Return a boolean value indicating if this effect is able to be
+	 * calculated based on the effect data. This is *not* regarding the
+	 * fx->flag, that is tested by the system, this is just if the data
+	 * validates (for example, a lattice will return false if the lattice
+	 * object is not defined).
+	 *
+	 * This function is optional (assumes never disabled if not present).
+	 */
+	bool (*isDisabled)(struct ShaderFxData *fx, int userRenderParams);
+
+	/* Add the appropriate relations to the dependency graph.
+	 *
+	 * This function is optional.
+	 */
+	void (*updateDepsgraph)(struct ShaderFxData *fx,
+	                        const struct ModifierUpdateDepsgraphContext *ctx);
+ 
+	/* Should return true if the effect needs to be recalculated on time
+	 * changes.
+	 *
+	 * This function is optional (assumes false if not present).
+	 */
+	bool (*dependsOnTime)(struct ShaderFxData *fx);
+
+
+	/* Should call the given walk function on with a pointer to each Object
+	 * pointer that the effect data stores. This is used for linking on file
+	 * load and for unlinking objects or forwarding object references.
+	 *
+	 * This function is optional.
+	 */
+	void (*foreachObjectLink)(struct ShaderFxData *fx, struct Object *ob,
+	                          ShaderFxObjectWalkFunc walk, void *userData);
+
+	/* Should call the given walk function with a pointer to each ID
+	 * pointer (i.e. each datablock pointer) that the effect data
+	 * stores. This is used for linking on file load and for
+	 * unlinking datablocks or forwarding datablock references.
+	 *
+	 * This function is optional. If it is not present, foreachObjectLink
+	 * will be used.
+	 */
+	void (*foreachIDLink)(struct ShaderFxData *fx, struct Object *ob,
+	                      ShaderFxIDWalkFunc walk, void *userData);
+} ShaderFxTypeInfo;
+
+/* Initialize  global data (type info and some common global storages). */
+void BKE_shaderfx_init(void);
+
+const ShaderFxTypeInfo *BKE_shaderfxType_getInfo(ShaderFxType type);
+struct ShaderFxData  *BKE_shaderfx_new(int type);
+void BKE_shaderfx_free_ex(struct ShaderFxData *fx, const int flag);
+void BKE_shaderfx_free(struct ShaderFxData *fx);
+bool BKE_shaderfx_unique_name(struct ListBase *shaderfx, struct ShaderFxData *fx);
+bool BKE_shaderfx_dependsOnTime(struct ShaderFxData *fx);
+struct ShaderFxData *BKE_shaderfx_findByType(struct Object *ob, ShaderFxType type);
+struct ShaderFxData *BKE_shaderfx_findByName(struct Object *ob, const char *name);
+void BKE_shaderfx_copyData_generic(const struct ShaderFxData *fx_src, struct ShaderFxData *fx_dst);
+void BKE_shaderfx_copyData(struct ShaderFxData *fx, struct ShaderFxData *target);
+void BKE_shaderfx_copyData_ex(struct ShaderFxData *fx, struct ShaderFxData *target, const int flag);
+void BKE_shaderfx_foreachIDLink(struct Object *ob, ShaderFxIDWalkFunc walk, void *userData);
+
+bool BKE_shaderfx_has_gpencil(struct Object *ob);
+
+#endif /* __BKE_SHADER_FX_H__ */
diff --git a/source/blender/blenkernel/CMakeLists.txt b/source/blender/blenkernel/CMakeLists.txt
index 01910bffdb0..7169597f100 100644
--- a/source/blender/blenkernel/CMakeLists.txt
+++ b/source/blender/blenkernel/CMakeLists.txt
@@ -38,6 +38,8 @@ set(INC
 	../makesrna
 	../bmesh
 	../modifiers
+	../gpencil_modifiers
+	../shader_fx
 	../nodes
 	../physics
 	../render/extern/include
@@ -115,6 +117,7 @@ set(SRC
 	intern/font.c
 	intern/freestyle.c
 	intern/gpencil.c
+	intern/gpencil_modifier.c
 	intern/icons.c
 	intern/icons_rasterize.c
 	intern/idcode.c
@@ -180,6 +183,7 @@ set(SRC
 	intern/seqeffects.c
 	intern/seqmodifier.c
 	intern/sequencer.c
+	intern/shader_fx.c
 	intern/shrinkwrap.c
 	intern/smoke.c
 	intern/softbody.c
@@ -259,6 +263,7 @@ set(SRC
 	BKE_freestyle.h
 	BKE_global.h
 	BKE_gpencil.h
+	BKE_gpencil_modifier.h
 	BKE_icons.h
 	BKE_idcode.h
 	BKE_idprop.h
@@ -306,6 +311,7 @@ set(SRC
 	BKE_scene.h
 	BKE_screen.h
 	BKE_sequencer.h
+	BKE_shader_fx.h
 	BKE_shrinkwrap.h
 	BKE_smoke.h
 	BKE_softbody.h
diff --git a/source/blender/blenkernel/intern/anim_sys.c b/source/blender/blenkernel/intern/anim_sys.c
index fd7497f9ba1..7dfedfe6c06 100644
--- a/source/blender/blenkernel/intern/anim_sys.c
+++ b/source/blender/blenkernel/intern/anim_sys.c
@@ -104,6 +104,7 @@ bool id_type_can_have_animdata(const short id_type)
 		case ID_MSK:
 		case ID_GD:
 		case ID_CF:
+		case ID_PAL:
 			return true;
 
 		/* no AnimData */
@@ -1150,6 +1151,9 @@ void BKE_animdata_main_cb(Main *bmain, ID_AnimData_Edit_Callback func, void *use
 	/* grease pencil */
 	ANIMDATA_IDS_CB(bmain->gpencil.first);
 
+	/* palettes */
+	ANIMDATA_IDS_CB(bmain->palettes.first);
+
 	/* cache files */
 	ANIMDATA_IDS_CB(bmain->cachefiles.first);
 }
@@ -2925,6 +2929,9 @@ void BKE_animsys_evaluate_all_animation(Main *main, Depsgraph *depsgraph, Scene
 	/* grease pencil */
 	EVAL_ANIM_IDS(main->gpencil.first, ADT_RECALC_ANIM);
 
+	/* palettes */
+	EVAL_ANIM_IDS(main->palettes.first, ADT_RECALC_ANIM);
+
 	/* cache files */
 	EVAL_ANIM_IDS(main->cachefiles.first, ADT_RECALC_ANIM);
 
diff --git a/source/blender/blenkernel/intern/brush.c b/source/blender/blenkernel/intern/brush.c
index 42cd7968321..598eb9b5b54 100644
--- a/source/blender/blenkernel/intern/brush.c
+++ b/source/blender/blenkernel/intern/brush.c
@@ -29,6 +29,7 @@
 #include "DNA_brush_types.h"
 #include "DNA_scene_types.h"
 #include "DNA_object_types.h"
+#include "DNA_gpencil_types.h"
 
 #include "BLI_math.h"
 #include "BLI_blenlib.h"
@@ -36,6 +37,7 @@
 
 #include "BKE_brush.h"
 #include "BKE_colortools.h"
+#include "BKE_context.h"
 #include "BKE_global.h"
 #include "BKE_library.h"
 #include "BKE_library_query.h"
@@ -129,6 +131,7 @@ static void brush_defaults(Brush *brush)
 
 	brush->stencil_dimension[0] = 256;
 	brush->stencil_dimension[1] = 256;
+
 }
 
 /* Datablock add/copy/free/make_local */
@@ -164,6 +167,368 @@ Brush *BKE_brush_add(Main *bmain, const char *name, const eObjectMode ob_mode)
 	return brush;
 }
 
+/* add a new gp-brush */
+Brush *BKE_brush_add_gpencil(Main *bmain, ToolSettings *ts, const char *name)
+{
+	Brush *brush;
+	Paint *paint = BKE_brush_get_gpencil_paint(ts);
+	brush = BKE_brush_add(bmain, name, OB_MODE_GPENCIL_PAINT);
+
+	BKE_paint_brush_set(paint, brush);
+	id_us_min(&brush->id);
+
+	/* grease pencil basic settings */
+	brush->size = 3;
+
+	brush->gpencil_settings = MEM_callocN(sizeof(BrushGpencilSettings), "BrushGpencilSettings");
+
+	brush->gpencil_settings->draw_smoothlvl = 1;
+	brush->gpencil_settings->flag = 0;
+	brush->gpencil_settings->flag |= GP_BRUSH_USE_PRESSURE;
+	brush->gpencil_settings->draw_sensitivity = 1.0f;
+	brush->gpencil_settings->draw_strength = 1.0f;
+	brush->gpencil_settings->draw_jitter = 0.0f;
+	brush->gpencil_settings->flag |= GP_BRUSH_USE_JITTER_PRESSURE;
+	brush->gpencil_settings->icon_id = GP_BRUSH_ICON_PEN;
+
+	/* curves */
+	brush->gpencil_settings->curve_sensitivity = curvemapping_add(1, 0.0f, 0.0f, 1.0f, 1.0f);
+	brush->gpencil_settings->curve_strength = curvemapping_add(1, 0.0f, 0.0f, 1.0f, 1.0f);
+	brush->gpencil_settings->curve_jitter = curvemapping_add(1, 0.0f, 0.0f, 1.0f, 1.0f);
+
+	/* return brush */
+	return brush;
+}
+
+Paint *BKE_brush_get_gpencil_paint(ToolSettings *ts)
+{
+	/* alloc paint session */
+	if (ts->gp_paint == NULL) {
+		ts->gp_paint = MEM_callocN(sizeof(GpPaint), "GpPaint");
+	}
+
+	return &ts->gp_paint->paint;
+}
+
+/* grease pencil cumapping->preset */
+typedef enum eGPCurveMappingPreset {
+	GPCURVE_PRESET_PENCIL = 0,
+	GPCURVE_PRESET_INK = 1,
+	GPCURVE_PRESET_INKNOISE = 2,
+} eGPCurveMappingPreset;
+
+static void brush_gpencil_curvemap_reset(CurveMap *cuma, int preset)
+{
+	if (cuma->curve)
+		MEM_freeN(cuma->curve);
+
+	cuma->totpoint = 3;
+	cuma->curve = MEM_callocN(cuma->totpoint * sizeof(CurveMapPoint), __func__);
+
+	switch (preset) {
+		case GPCURVE_PRESET_PENCIL:
+			cuma->curve[0].x = 0.0f;
+			cuma->curve[0].y = 0.0f;
+			cuma->curve[1].x = 0.75115f;
+			cuma->curve[1].y = 0.25f;
+			cuma->curve[2].x = 1.0f;
+			cuma->curve[2].y = 1.0f;
+			break;
+		case GPCURVE_PRESET_INK:
+			cuma->curve[0].x = 0.0f;
+			cuma->curve[0].y = 0.0f;
+			cuma->curve[1].x = 0.63448f;
+			cuma->curve[1].y = 0.375f;
+			cuma->curve[2].x = 1.0f;
+			cuma->curve[2].y = 1.0f;
+			break;
+		case GPCURVE_PRESET_INKNOISE:
+			cuma->curve[0].x = 0.0f;
+			cuma->curve[0].y = 0.0f;
+			cuma->curve[1].x = 0.63134f;
+			cuma->curve[1].y = 0.3625f;
+			cuma->curve[2].x = 1.0f;
+			cuma->curve[2].y = 1.0f;
+			break;
+	}
+
+	if (cuma->table) {
+		MEM_freeN(cuma->table);
+		cuma->table = NULL;
+	}
+}
+
+/* create a set of grease pencil presets */
+void BKE_brush_gpencil_presets(bContext *C)
+{
+#define SMOOTH_STROKE_RADIUS 40
+#define SMOOTH_STROKE_FACTOR 0.9f
+
+	ToolSettings *ts = CTX_data_tool_settings(C);
+	Paint *paint = BKE_brush_get_gpencil_paint(ts);
+	Main *bmain = CTX_data_main(C);
+
+	Brush *brush, *deft;
+	CurveMapping *custom_curve;
+
+	/* Pencil brush */
+	brush = BKE_brush_add_gpencil(bmain, ts, "Draw Pencil");
+	brush->size = 25.0f;
+	brush->gpencil_settings->flag |= (GP_BRUSH_USE_PRESSURE | GP_BRUSH_ENABLE_CURSOR);
+	brush->gpencil_settings->draw_sensitivity = 1.0f;
+
+	brush->gpencil_settings->draw_strength = 0.6f;
+	brush->gpencil_settings->flag |= GP_BRUSH_USE_STENGTH_PRESSURE;
+
+	brush->gpencil_settings->draw_random_press = 0.0f;
+
+	brush->gpencil_settings->draw_jitter = 0.0f;
+	brush->gpencil_settings->flag |= GP_BRUSH_USE_JITTER_PRESSURE;
+
+	brush->gpencil_settings->draw_angle = 0.0f;
+	brush->gpencil_settings->draw_angle_factor = 0.0f;
+
+	brush->gpencil_settings->flag |= GP_BRUSH_GROUP_SETTINGS;
+	brush->gpencil_settings->draw_smoothfac = 0.5f;
+	brush->gpencil_settings->draw_smoothlvl = 1;
+	brush->gpencil_settings->thick_smoothfac = 1.0f;
+	brush->gpencil_settings->thick_smoothlvl = 3;
+	brush->gpencil_settings->draw_subdivide = 1;
+	brush->gpencil_settings->draw_random_sub = 0.0f;
+	brush->gpencil_settings->icon_id = GP_BRUSH_ICON_PENCIL;
+	brush->gpencil_settings->brush_type = GP_BRUSH_TYPE_DRAW;
+
+	brush->smooth_stroke_radius = SMOOTH_STROKE_RADIUS;
+	brush->smooth_stroke_factor = SMOOTH_STROKE_FACTOR;
+
+	/* Pen brush */
+	brush = BKE_brush_add_gpencil(bmain, ts, "Draw Pen");
+	deft = brush; /* save default brush */
+	brush->size = 30.0f;
+	brush->gpencil_settings->flag |= (GP_BRUSH_USE_PRESSURE | GP_BRUSH_ENABLE_CURSOR);
+	brush->gpencil_settings->draw_sensitivity = 1.0f;
+
+	brush->gpencil_settings->draw_strength = 1.0f;
+	brush->gpencil_settings->flag |= GP_BRUSH_USE_STENGTH_PRESSURE;
+
+	brush->gpencil_settings->draw_random_press = 0.0f;
+	brush->gpencil_settings->draw_random_strength = 0.0f;
+
+	brush->gpencil_settings->draw_jitter = 0.0f;
+	brush->gpencil_settings->flag |= GP_BRUSH_USE_JITTER_PRESSURE;
+
+	brush->gpencil_settings->draw_angle = 0.0f;
+	brush->gpencil_settings->draw_angle_factor = 0.0f;
+
+	brush->gpencil_settings->flag |= GP_BRUSH_GROUP_SETTINGS;
+	brush->gpencil_settings->draw_smoothfac = 0.5f;
+	brush->gpencil_settings->draw_smoothlvl = 1;
+	brush->gpencil_settings->draw_subdivide = 1;
+	brush->gpencil_settings->thick_smoothfac = 1.0f;
+	brush->gpencil_settings->thick_smoothlvl = 3;
+	brush->gpencil_settings->draw_random_sub = 0.0f;
+	brush->gpencil_settings->icon_id = GP_BRUSH_ICON_PEN;
+	brush->gpencil_settings->brush_type = GP_BRUSH_TYPE_DRAW;
+
+	brush->smooth_stroke_radius = SMOOTH_STROKE_RADIUS;
+	brush->smooth_stroke_factor = SMOOTH_STROKE_FACTOR;
+
+	/* Ink brush */
+	brush = BKE_brush_add_gpencil(bmain, ts, "Draw Ink");
+	brush->size = 60.0f;
+	brush->gpencil_settings->flag |= (GP_BRUSH_USE_PRESSURE | GP_BRUSH_ENABLE_CURSOR);
+	brush->gpencil_settings->draw_sensitivity = 1.6f;
+
+	brush->gpencil_settings->draw_strength = 1.0f;
+
+	brush->gpencil_settings->draw_random_press = 0.0f;
+
+	brush->gpencil_settings->draw_jitter = 0.0f;
+	brush->gpencil_settings->flag |= GP_BRUSH_USE_JITTER_PRESSURE;
+
+	brush->gpencil_settings->draw_angle = 0.0f;
+	brush->gpencil_settings->draw_angle_factor = 0.0f;
+
+	brush->gpencil_settings->flag |= GP_BRUSH_GROUP_SETTINGS;
+	brush->gpencil_settings->draw_smoothfac = 0.5f;
+	brush->gpencil_settings->draw_smoothlvl = 1;
+	brush->gpencil_settings->thick_smoothfac = 1.0f;
+	brush->gpencil_settings->thick_smoothlvl = 3;
+	brush->gpencil_settings->draw_subdivide = 1;
+	brush->gpencil_settings->draw_random_sub = 0.0f;
+	brush->gpencil_settings->icon_id = GP_BRUSH_ICON_INK;
+	brush->gpencil_settings->brush_type = GP_BRUSH_TYPE_DRAW;
+
+	brush->smooth_stroke_radius = SMOOTH_STROKE_RADIUS;
+	brush->smooth_stroke_factor = SMOOTH_STROKE_FACTOR;
+
+	/* Curve */
+	custom_curve = brush->gpencil_settings->curve_sensitivity;
+	curvemapping_set_defaults(custom_curve, 0, 0.0f, 0.0f, 1.0f, 1.0f);
+	curvemapping_initialize(custom_curve);
+	brush_gpencil_curvemap_reset(custom_curve->cm, GPCURVE_PRESET_INK);
+
+	/* Ink Noise brush */
+	brush = BKE_brush_add_gpencil(bmain, ts, "Draw Noise");
+	brush->size = 60.0f;
+	brush->gpencil_settings->flag |= (GP_BRUSH_USE_PRESSURE | GP_BRUSH_ENABLE_CURSOR);
+	brush->gpencil_settings->draw_sensitivity = 1.0f;
+
+	brush->gpencil_settings->draw_strength = 1.0f;
+
+	brush->gpencil_settings->flag |= GP_BRUSH_GROUP_RANDOM;
+	brush->gpencil_settings->draw_random_press = 0.7f;
+	brush->gpencil_settings->draw_random_strength = 0.0f;
+
+	brush->gpencil_settings->draw_jitter = 0.0f;
+	brush->gpencil_settings->flag |= GP_BRUSH_USE_JITTER_PRESSURE;
+
+	brush->gpencil_settings->draw_angle = 0.0f;
+	brush->gpencil_settings->draw_angle_factor = 0.0f;
+
+	brush->gpencil_settings->flag |= GP_BRUSH_GROUP_SETTINGS;
+	brush->gpencil_settings->draw_smoothfac = 1.0f;
+	brush->gpencil_settings->draw_smoothlvl = 2;
+	brush->gpencil_settings->thick_smoothfac = 0.5f;
+	brush->gpencil_settings->thick_smoothlvl = 2;
+	brush->gpencil_settings->draw_subdivide = 1;
+	brush->gpencil_settings->draw_random_sub = 0.0f;
+	brush->gpencil_settings->icon_id = GP_BRUSH_ICON_INKNOISE;
+	brush->gpencil_settings->brush_type = GP_BRUSH_TYPE_DRAW;
+
+	brush->smooth_stroke_radius = SMOOTH_STROKE_RADIUS;
+	brush->smooth_stroke_factor = SMOOTH_STROKE_FACTOR;
+
+	/* Curve */
+	custom_curve = brush->gpencil_settings->curve_sensitivity;
+	curvemapping_set_defaults(custom_curve, 0, 0.0f, 0.0f, 1.0f, 1.0f);
+	curvemapping_initialize(custom_curve);
+	brush_gpencil_curvemap_reset(custom_curve->cm, GPCURVE_PRESET_INKNOISE);
+
+	/* Block Basic brush */
+	brush = BKE_brush_add_gpencil(bmain, ts, "Draw Block");
+	brush->size = 150.0f;
+	brush->gpencil_settings->flag |= (GP_BRUSH_USE_PRESSURE | GP_BRUSH_ENABLE_CURSOR);
+	brush->gpencil_settings->draw_sensitivity = 1.0f;
+
+	brush->gpencil_settings->draw_strength = 0.7f;
+	brush->gpencil_settings->flag |= GP_BRUSH_USE_STENGTH_PRESSURE;
+
+	brush->gpencil_settings->draw_random_press = 0.0f;
+
+	brush->gpencil_settings->draw_jitter = 0.0f;
+	brush->gpencil_settings->flag |= GP_BRUSH_USE_JITTER_PRESSURE;
+
+	brush->gpencil_settings->draw_angle = 0.0f;
+	brush->gpencil_settings->draw_angle_factor = 0.0f;
+
+	brush->gpencil_settings->flag |= GP_BRUSH_GROUP_SETTINGS;
+	brush->gpencil_settings->draw_smoothfac = 0.0f;
+	brush->gpencil_settings->draw_smoothlvl = 1;
+	brush->gpencil_settings->thick_smoothfac = 1.0f;
+	brush->gpencil_settings->thick_smoothlvl = 3;
+	brush->gpencil_settings->draw_subdivide = 0;
+	brush->gpencil_settings->draw_random_sub = 0;
+	brush->gpencil_settings->icon_id = GP_BRUSH_ICON_BLOCK;
+	brush->gpencil_settings->brush_type = GP_BRUSH_TYPE_DRAW;
+
+	brush->smooth_stroke_radius = SMOOTH_STROKE_RADIUS;
+	brush->smooth_stroke_factor = SMOOTH_STROKE_FACTOR;
+
+	/* Marker brush */
+	brush = BKE_brush_add_gpencil(bmain, ts, "Draw Marker");
+	brush->size = 80.0f;
+	brush->gpencil_settings->flag |= (GP_BRUSH_USE_PRESSURE | GP_BRUSH_ENABLE_CURSOR);
+	brush->gpencil_settings->draw_sensitivity = 1.0f;
+
+	brush->gpencil_settings->draw_strength = 1.0f;
+
+	brush->gpencil_settings->flag |= GP_BRUSH_GROUP_RANDOM;
+	brush->gpencil_settings->draw_random_press = 0.374f;
+	brush->gpencil_settings->draw_random_strength = 0.0f;
+
+	brush->gpencil_settings->draw_jitter = 0.0f;
+	brush->gpencil_settings->flag |= GP_BRUSH_USE_JITTER_PRESSURE;
+
+	brush->gpencil_settings->draw_angle = M_PI_4; /* 45 degrees */
+	brush->gpencil_settings->draw_angle_factor = 1.0f;
+
+	brush->gpencil_settings->flag |= GP_BRUSH_GROUP_SETTINGS;
+	brush->gpencil_settings->draw_smoothfac = 0.5f;
+	brush->gpencil_settings->draw_smoothlvl = 1;
+	brush->gpencil_settings->thick_smoothfac = 1.0f;
+	brush->gpencil_settings->thick_smoothlvl = 3;
+	brush->gpencil_settings->draw_subdivide = 1;
+	brush->gpencil_settings->draw_random_sub = 0.0f;
+	brush->gpencil_settings->icon_id = GP_BRUSH_ICON_MARKER;
+	brush->gpencil_settings->brush_type = GP_BRUSH_TYPE_DRAW;
+
+	brush->smooth_stroke_radius = SMOOTH_STROKE_RADIUS;
+	brush->smooth_stroke_factor = SMOOTH_STROKE_FACTOR;
+
+	/* Fill brush */
+	brush = BKE_brush_add_gpencil(bmain, ts, "Fill Area");
+	brush->size = 1.0f;
+	brush->gpencil_settings->flag |= GP_BRUSH_ENABLE_CURSOR;
+	brush->gpencil_settings->draw_sensitivity = 1.0f;
+	brush->gpencil_settings->fill_leak = 3;
+	brush->gpencil_settings->fill_threshold = 0.1f;
+	brush->gpencil_settings->fill_simplylvl = 1;
+	brush->gpencil_settings->icon_id = GP_BRUSH_ICON_FILL;
+	brush->gpencil_settings->brush_type = GP_BRUSH_TYPE_FILL;
+
+	brush->gpencil_settings->draw_smoothfac = 0.5f;
+	brush->gpencil_settings->draw_smoothlvl = 1;
+	brush->gpencil_settings->thick_smoothfac = 1.0f;
+	brush->gpencil_settings->thick_smoothlvl = 3;
+	brush->gpencil_settings->draw_subdivide = 1;
+
+	brush->smooth_stroke_radius = SMOOTH_STROKE_RADIUS;
+	brush->smooth_stroke_factor = SMOOTH_STROKE_FACTOR;
+
+	brush->gpencil_settings->draw_strength = 1.0f;
+
+	/* Soft Eraser brush */
+	brush = BKE_brush_add_gpencil(bmain, ts, "Eraser Soft");
+	brush->size = 30.0f;
+	brush->gpencil_settings->flag |= (GP_BRUSH_ENABLE_CURSOR | GP_BRUSH_DEFAULT_ERASER);
+	brush->gpencil_settings->icon_id = GP_BRUSH_ICON_ERASE_SOFT;
+	brush->gpencil_settings->brush_type = GP_BRUSH_TYPE_ERASE;
+	brush->gpencil_settings->eraser_mode = GP_BRUSH_ERASER_SOFT;
+
+	/* Hard Eraser brush */
+	brush = BKE_brush_add_gpencil(bmain, ts, "Eraser Hard");
+	brush->size = 30.0f;
+	brush->gpencil_settings->flag |= GP_BRUSH_ENABLE_CURSOR;
+	brush->gpencil_settings->icon_id = GP_BRUSH_ICON_ERASE_HARD;
+	brush->gpencil_settings->brush_type = GP_BRUSH_TYPE_ERASE;
+	brush->gpencil_settings->eraser_mode = GP_BRUSH_ERASER_HARD;
+
+	/* Stroke Eraser brush */
+	brush = BKE_brush_add_gpencil(bmain, ts, "Eraser Stroke");
+	brush->size = 30.0f;
+	brush->gpencil_settings->flag |= GP_BRUSH_ENABLE_CURSOR;
+	brush->gpencil_settings->icon_id = GP_BRUSH_ICON_ERASE_STROKE;
+	brush->gpencil_settings->brush_type = GP_BRUSH_TYPE_ERASE;
+	brush->gpencil_settings->eraser_mode = GP_BRUSH_ERASER_STROKE;
+
+	/* set defaut brush */
+	BKE_paint_brush_set(paint, deft);
+
+}
+
+/* get the active gp-brush for editing */
+Brush *BKE_brush_getactive_gpencil(ToolSettings *ts)
+{
+	/* error checking */
+	if (ELEM(NULL, ts, ts->gp_paint)) {
+		return NULL;
+	}
+	Paint *paint = &ts->gp_paint->paint;
+
+	return paint->brush;
+}
+
 struct Brush *BKE_brush_first_search(struct Main *bmain, const eObjectMode ob_mode)
 {
 	Brush *brush;
@@ -197,6 +562,12 @@ void BKE_brush_copy_data(Main *UNUSED(bmain), Brush *brush_dst, const Brush *bru
 	}
 
 	brush_dst->curve = curvemapping_copy(brush_src->curve);
+	if (brush_src->gpencil_settings != NULL) {
+		brush_dst->gpencil_settings = MEM_dupallocN(brush_src->gpencil_settings);
+		brush_dst->gpencil_settings->curve_sensitivity = curvemapping_copy(brush_src->gpencil_settings->curve_sensitivity);
+		brush_dst->gpencil_settings->curve_strength = curvemapping_copy(brush_src->gpencil_settings->curve_strength);
+		brush_dst->gpencil_settings->curve_jitter = curvemapping_copy(brush_src->gpencil_settings->curve_jitter);
+	}
 
 	/* enable fake user by default */
 	id_fake_user_set(&brush_dst->id);
@@ -215,11 +586,18 @@ void BKE_brush_free(Brush *brush)
 	if (brush->icon_imbuf) {
 		IMB_freeImBuf(brush->icon_imbuf);
 	}
-
 	curvemapping_free(brush->curve);
 
+	if (brush->gpencil_settings != NULL) {
+		curvemapping_free(brush->gpencil_settings->curve_sensitivity);
+		curvemapping_free(brush->gpencil_settings->curve_strength);
+		curvemapping_free(brush->gpencil_settings->curve_jitter);
+		MEM_SAFE_FREE(brush->gpencil_settings);
+	}
+
 	MEM_SAFE_FREE(brush->gradient);
 
+
 	BKE_previewimg_free(&(brush->preview));
 }
 
diff --git a/source/blender/blenkernel/intern/colortools.c b/source/blender/blenkernel/intern/colortools.c
index ff4795afe87..d18572a57f6 100644
--- a/source/blender/blenkernel/intern/colortools.c
+++ b/source/blender/blenkernel/intern/colortools.c
@@ -282,6 +282,7 @@ void curvemap_reset(CurveMap *cuma, const rctf *clipr, int preset, int slope)
 		case CURVE_PRESET_MID9: cuma->totpoint = 9; break;
 		case CURVE_PRESET_ROUND: cuma->totpoint = 4; break;
 		case CURVE_PRESET_ROOT: cuma->totpoint = 4; break;
+		case CURVE_PRESET_GAUSS: cuma->totpoint = 7; break;
 	}
 
 	cuma->curve = MEM_callocN(cuma->totpoint * sizeof(CurveMapPoint), "curve points");
@@ -352,6 +353,24 @@ void curvemap_reset(CurveMap *cuma, const rctf *clipr, int preset, int slope)
 			cuma->curve[3].x = 1;
 			cuma->curve[3].y = 0;
 			break;
+		case CURVE_PRESET_GAUSS:
+			cuma->curve[0].x = 0;
+			cuma->curve[0].y = 0.025f;
+			cuma->curve[1].x = 0.16f;
+			cuma->curve[1].y = 0.135f;
+			cuma->curve[2].x = 0.298f;
+			cuma->curve[2].y = 0.36f;
+
+			cuma->curve[3].x = 0.50f;
+			cuma->curve[3].y = 1.0f;
+
+			cuma->curve[4].x = 0.70f;
+			cuma->curve[4].y = 0.36f;
+			cuma->curve[5].x = 0.84f;
+			cuma->curve[5].y = 0.135f;
+			cuma->curve[6].x = 1.0f;
+			cuma->curve[6].y = 0.025f;
+			break;
 	}
 
 	/* mirror curve in x direction to have positive slope
diff --git a/source/blender/blenkernel/intern/context.c b/source/blender/blenkernel/intern/context.c
index 3dfe9732062..84ca143dc55 100644
--- a/source/blender/blenkernel/intern/context.c
+++ b/source/blender/blenkernel/intern/context.c
@@ -1014,6 +1014,10 @@ int CTX_data_mode_enum_ex(const Object *obedit, const Object *ob, const eObjectM
 			else if (object_mode & OB_MODE_VERTEX_PAINT) return CTX_MODE_PAINT_VERTEX;
 			else if (object_mode & OB_MODE_TEXTURE_PAINT) return CTX_MODE_PAINT_TEXTURE;
 			else if (object_mode & OB_MODE_PARTICLE_EDIT) return CTX_MODE_PARTICLE;
+			else if (object_mode & OB_MODE_GPENCIL_PAINT) return CTX_MODE_GPENCIL_PAINT;
+			else if (object_mode & OB_MODE_GPENCIL_EDIT) return CTX_MODE_GPENCIL_EDIT;
+			else if (object_mode & OB_MODE_GPENCIL_SCULPT) return CTX_MODE_GPENCIL_SCULPT;
+			else if (object_mode & OB_MODE_GPENCIL_WEIGHT) return CTX_MODE_GPENCIL_WEIGHT;
 		}
 	}
 
@@ -1044,6 +1048,10 @@ static const char *data_mode_strings[] = {
 	"imagepaint",
 	"particlemode",
 	"objectmode",
+	"greasepencil_paint",
+	"greasepencil_edit",
+	"greasepencil_sculpt",
+	"greasepencil_weight",
 	NULL
 };
 BLI_STATIC_ASSERT(ARRAY_SIZE(data_mode_strings) == CTX_MODE_NUM + 1, "Must have a string for each context mode")
@@ -1212,17 +1220,7 @@ bGPDlayer *CTX_data_active_gpencil_layer(const bContext *C)
 	return ctx_data_pointer_get(C, "active_gpencil_layer");
 }
 
-bGPDpalette *CTX_data_active_gpencil_palette(const bContext *C)
-{
-	return ctx_data_pointer_get(C, "active_gpencil_palette");
-}
-
-bGPDpalettecolor *CTX_data_active_gpencil_palettecolor(const bContext *C)
-{
-	return ctx_data_pointer_get(C, "active_gpencil_palettecolor");
-}
-
-bGPDbrush *CTX_data_active_gpencil_brush(const bContext *C)
+Brush *CTX_data_active_gpencil_brush(const bContext *C)
 {
 	return ctx_data_pointer_get(C, "active_gpencil_brush");
 }
diff --git a/source/blender/blenkernel/intern/deform.c b/source/blender/blenkernel/intern/deform.c
index d08e3643ca7..ddf9840a32e 100644
--- a/source/blender/blenkernel/intern/deform.c
+++ b/source/blender/blenkernel/intern/deform.c
@@ -74,7 +74,9 @@ bDeformGroup *BKE_defgroup_new(Object *ob, const char *name)
 	BLI_addtail(&ob->defbase, defgroup);
 	defgroup_unique_name(defgroup, ob);
 
-	BKE_mesh_batch_cache_dirty(ob->data, BKE_MESH_BATCH_DIRTY_ALL);
+	if (ob->type != OB_GPENCIL) {
+		BKE_mesh_batch_cache_dirty(ob->data, BKE_MESH_BATCH_DIRTY_ALL);
+	}
 
 	return defgroup;
 }
diff --git a/source/blender/blenkernel/intern/gpencil.c b/source/blender/blenkernel/intern/gpencil.c
index e89508fd6c0..de3f891f9f9 100644
--- a/source/blender/blenkernel/intern/gpencil.c
+++ b/source/blender/blenkernel/intern/gpencil.c
@@ -39,26 +39,83 @@
 #include "BLI_blenlib.h"
 #include "BLI_utildefines.h"
 #include "BLI_math_vector.h"
+#include "BLI_math_color.h"
 #include "BLI_string_utils.h"
+#include "BLI_rand.h"
+#include "BLI_ghash.h"
 
 #include "BLT_translation.h"
 
+#include "DNA_anim_types.h"
+#include "DNA_meshdata_types.h"
+#include "DNA_material_types.h"
 #include "DNA_gpencil_types.h"
 #include "DNA_userdef_types.h"
 #include "DNA_scene_types.h"
+#include "DNA_object_types.h"
 
+#include "BKE_context.h"
+#include "BKE_action.h"
 #include "BKE_animsys.h"
 #include "BKE_global.h"
 #include "BKE_gpencil.h"
 #include "BKE_colortools.h"
+#include "BKE_icons.h"
 #include "BKE_library.h"
 #include "BKE_main.h"
+#include "BKE_object.h"
+#include "BKE_material.h"
 
+#include "DEG_depsgraph.h"
 
 /* ************************************************** */
-/* GENERAL STUFF */
+/* Draw Engine */
 
-/* --------- Memory Management ------------ */
+void(*BKE_gpencil_batch_cache_dirty_cb)(bGPdata *gpd) = NULL;
+void(*BKE_gpencil_batch_cache_free_cb)(bGPdata *gpd) = NULL;
+
+void BKE_gpencil_batch_cache_dirty(bGPdata *gpd)
+{
+	if (gpd) {
+		DEG_id_tag_update(&gpd->id, OB_RECALC_DATA);
+		BKE_gpencil_batch_cache_dirty_cb(gpd);
+	}
+}
+
+void BKE_gpencil_batch_cache_free(bGPdata *gpd)
+{
+	if (gpd) {
+		BKE_gpencil_batch_cache_free_cb(gpd);
+	}
+}
+
+/* ************************************************** */
+/* Memory Management */
+
+/* clean vertex groups weights */
+void BKE_gpencil_free_point_weights(MDeformVert *dvert)
+{
+	if (dvert == NULL) {
+		return;
+	}
+	MEM_SAFE_FREE(dvert->dw);
+}
+
+void BKE_gpencil_free_stroke_weights(bGPDstroke *gps)
+{
+	if (gps == NULL) {
+		return;
+	}
+
+	if (gps->dvert == NULL) {
+		return;
+	}
+
+	for (int i = 0; i < gps->totpoints; i++) {
+		MDeformVert *dvert = &gps->dvert[i];
+		BKE_gpencil_free_point_weights(dvert);
+	}
+}
 
 /* free stroke, doesn't unlink from any listbase */
 void BKE_gpencil_free_stroke(bGPDstroke *gps)
@@ -66,10 +123,14 @@ void BKE_gpencil_free_stroke(bGPDstroke *gps)
 	if (gps == NULL) {
 		return;
 	}
-
 	/* free stroke memory arrays, then stroke itself */
-	if (gps->points)
+	if (gps->points) {
 		MEM_freeN(gps->points);
+	}
+	if (gps->dvert) {
+		BKE_gpencil_free_stroke_weights(gps);
+		MEM_freeN(gps->dvert);
+	}
 	if (gps->triangles)
 		MEM_freeN(gps->triangles);
 
@@ -92,6 +153,26 @@ bool BKE_gpencil_free_strokes(bGPDframe *gpf)
 	return changed;
 }
 
+/* Free strokes and colors belonging to a gp-frame */
+bool BKE_gpencil_free_frame_runtime_data(bGPDframe *derived_gpf)
+{
+	bGPDstroke *gps_next;
+	if (!derived_gpf) {
+		return false;
+	}
+
+	/* free strokes */
+	for (bGPDstroke *gps = derived_gpf->strokes.first; gps; gps = gps_next) {
+		gps_next = gps->next;
+		BKE_gpencil_free_stroke(gps);
+	}
+	BLI_listbase_clear(&derived_gpf->strokes);
+
+	MEM_SAFE_FREE(derived_gpf);
+
+	return true;
+}
+
 /* Free all of a gp-layer's frames */
 void BKE_gpencil_free_frames(bGPDlayer *gpl)
 {
@@ -111,101 +192,101 @@ void BKE_gpencil_free_frames(bGPDlayer *gpl)
 	gpl->actframe = NULL;
 }
 
-/* Free all of a gp-colors */
-static void free_gpencil_colors(bGPDpalette *palette)
-{
-	/* error checking */
-	if (palette == NULL) {
-		return;
-	}
 
-	/* free colors */
-	BLI_freelistN(&palette->colors);
-}
 
-/* Free all of the gp-palettes and colors */
-void BKE_gpencil_free_palettes(ListBase *list)
+/* Free all of the gp-layers for a viewport (list should be &gpd->layers or so) */
+void BKE_gpencil_free_layers(ListBase *list)
 {
-	bGPDpalette *palette_next;
+	bGPDlayer *gpl_next;
 
 	/* error checking */
-	if (list == NULL) {
-		return;
-	}
+	if (list == NULL) return;
 
-	/* delete palettes */
-	for (bGPDpalette *palette = list->first; palette; palette = palette_next) {
-		palette_next = palette->next;
-		/* free palette colors */
-		free_gpencil_colors(palette);
+	/* delete layers */
+	for (bGPDlayer *gpl = list->first; gpl; gpl = gpl_next) {
+		gpl_next = gpl->next;
 
-		MEM_freeN(palette);
+		/* free layers and their data */
+		BKE_gpencil_free_frames(gpl);
+		BLI_freelinkN(list, gpl);
 	}
-	BLI_listbase_clear(list);
 }
 
-/* Free all of the gp-brushes for a viewport (list should be &gpd->brushes or so) */
-void BKE_gpencil_free_brushes(ListBase *list)
+/* clear all runtime derived data */
+static void BKE_gpencil_clear_derived(bGPDlayer *gpl)
 {
-	bGPDbrush *brush_next;
+	GHashIterator gh_iter;
 
-	/* error checking */
-	if (list == NULL) {
+	if (gpl->runtime.derived_data == NULL) {
 		return;
 	}
 
-	/* delete brushes */
-	for (bGPDbrush *brush = list->first; brush; brush = brush_next) {
-		brush_next = brush->next;
-		/* free curves */
-		if (brush->cur_sensitivity) {
-			curvemapping_free(brush->cur_sensitivity);
-		}
-		if (brush->cur_strength) {
-			curvemapping_free(brush->cur_strength);
+	GHASH_ITER(gh_iter, gpl->runtime.derived_data) {
+		bGPDframe *gpf = (bGPDframe *)BLI_ghashIterator_getValue(&gh_iter);
+		if (gpf) {
+			BKE_gpencil_free_frame_runtime_data(gpf);
 		}
-		if (brush->cur_jitter) {
-			curvemapping_free(brush->cur_jitter);
-		}
-
-		MEM_freeN(brush);
 	}
-	BLI_listbase_clear(list);
 }
 
-/* Free all of the gp-layers for a viewport (list should be &gpd->layers or so) */
-void BKE_gpencil_free_layers(ListBase *list)
+/* Free all of the gp-layers temp data*/
+static void BKE_gpencil_free_layers_temp_data(ListBase *list)
 {
 	bGPDlayer *gpl_next;
 
 	/* error checking */
 	if (list == NULL) return;
-
 	/* delete layers */
 	for (bGPDlayer *gpl = list->first; gpl; gpl = gpl_next) {
 		gpl_next = gpl->next;
+		BKE_gpencil_clear_derived(gpl);
 
-		/* free layers and their data */
-		BKE_gpencil_free_frames(gpl);
-		BLI_freelinkN(list, gpl);
+		if (gpl->runtime.derived_data) {
+			BLI_ghash_free(gpl->runtime.derived_data, NULL, NULL);
+			gpl->runtime.derived_data = NULL;
+		}
+	}
+}
+
+/* Free temp gpf derived frames */
+void BKE_gpencil_free_derived_frames(bGPdata *gpd)
+{
+	/* error checking */
+	if (gpd == NULL) return;
+	for (bGPDlayer *gpl = gpd->layers.first; gpl; gpl = gpl->next) {
+		BKE_gpencil_clear_derived(gpl);
+
+		if (gpl->runtime.derived_data) {
+			BLI_ghash_free(gpl->runtime.derived_data, NULL, NULL);
+			gpl->runtime.derived_data = NULL;
+		}
 	}
 }
 
 /** Free (or release) any data used by this grease pencil (does not free the gpencil itself). */
-void BKE_gpencil_free(bGPdata *gpd, bool free_palettes)
+void BKE_gpencil_free(bGPdata *gpd, bool free_all)
 {
+	/* clear animation data */
 	BKE_animdata_free(&gpd->id, false);
 
 	/* free layers */
+	if (free_all) {
+		BKE_gpencil_free_layers_temp_data(&gpd->layers);
+	}
 	BKE_gpencil_free_layers(&gpd->layers);
 
-	/* free palettes */
-	if (free_palettes) {
-		BKE_gpencil_free_palettes(&gpd->palettes);
+	/* materials */
+	MEM_SAFE_FREE(gpd->mat);
+
+	/* free all data */
+	if (free_all) {
+		/* clear cache */
+		BKE_gpencil_batch_cache_free(gpd);
 	}
 }
 
-/* -------- Container Creation ---------- */
+/* ************************************************** */
+/* Container Creation */
 
 /* add a new gp-frame to the given layer */
 bGPDframe *BKE_gpencil_frame_addnew(bGPDlayer *gpl, int cframe)
@@ -329,28 +410,31 @@ bGPDlayer *BKE_gpencil_layer_addnew(bGPdata *gpd, const char *name, bool setacti
 	/* add to datablock */
 	BLI_addtail(&gpd->layers, gpl);
 
-	/* set basic settings */
-	copy_v4_v4(gpl->color, U.gpencil_new_layer_col);
-	/* Since GPv2 thickness must be 0 */
-	gpl->thickness = 0;
-
-	gpl->opacity = 1.0f;
+	/* annotation vs GP Object behaviour is slightly different */
+	if (gpd->flag & GP_DATA_ANNOTATIONS) {
+		/* set default color of new strokes for this layer */
+		copy_v4_v4(gpl->color, U.gpencil_new_layer_col);
+		gpl->opacity = 1.0f;
 
-	/* onion-skinning settings */
-	if (gpd->flag & GP_DATA_SHOW_ONIONSKINS)
-		gpl->flag |= GP_LAYER_ONIONSKIN;
+		/* set default thickness of new strokes for this layer */
+		gpl->thickness = 3;
 
-	gpl->flag |= (GP_LAYER_GHOST_PREVCOL | GP_LAYER_GHOST_NEXTCOL);
-
-	ARRAY_SET_ITEMS(gpl->gcolor_prev, 0.145098f, 0.419608f, 0.137255f); /* green */
-	ARRAY_SET_ITEMS(gpl->gcolor_next, 0.125490f, 0.082353f, 0.529412f); /* blue */
-
-	/* high quality fill by default */
-	gpl->flag |= GP_LAYER_HQ_FILL;
+		/* onion-skinning settings */
+		gpl->onion_flag |= GP_LAYER_ONIONSKIN;
+	}
+	else {
+		/* thickness parameter represents "thickness change", not absolute thickness */
+		gpl->thickness = 0;
+		gpl->opacity = 1.0f;
+	}
 
 	/* auto-name */
 	BLI_strncpy(gpl->info, name, sizeof(gpl->info));
-	BLI_uniquename(&gpd->layers, gpl, DATA_("GP_Layer"), '.', offsetof(bGPDlayer, info), sizeof(gpl->info));
+	BLI_uniquename(&gpd->layers, gpl,
+	               (gpd->flag & GP_DATA_ANNOTATIONS) ? DATA_("Note") : DATA_("GP_Layer"),
+	               '.',
+	               offsetof(bGPDlayer, info),
+	               sizeof(gpl->info));
 
 	/* make this one the active one */
 	if (setactive)
@@ -360,292 +444,153 @@ bGPDlayer *BKE_gpencil_layer_addnew(bGPdata *gpd, const char *name, bool setacti
 	return gpl;
 }
 
-/* add a new gp-palette and make it the active */
-bGPDpalette *BKE_gpencil_palette_addnew(bGPdata *gpd, const char *name, bool setactive)
-{
-	bGPDpalette *palette;
-
-	/* check that list is ok */
-	if (gpd == NULL) {
-		return NULL;
-	}
-
-	/* allocate memory and add to end of list */
-	palette = MEM_callocN(sizeof(bGPDpalette), "bGPDpalette");
-
-	/* add to datablock */
-	BLI_addtail(&gpd->palettes, palette);
-
-	/* set basic settings */
-	/* auto-name */
-	BLI_strncpy(palette->info, name, sizeof(palette->info));
-	BLI_uniquename(&gpd->palettes, palette, DATA_("GP_Palette"), '.', offsetof(bGPDpalette, info),
-	               sizeof(palette->info));
-
-	/* make this one the active one */
-	/* NOTE: Always make this active if there's nothing else yet (T50123) */
-	if ((setactive) || (gpd->palettes.first == gpd->palettes.last)) {
-		BKE_gpencil_palette_setactive(gpd, palette);
-	}
-
-	/* return palette */
-	return palette;
-}
-
-/* create a set of default drawing brushes with predefined presets */
-void BKE_gpencil_brush_init_presets(ToolSettings *ts)
+/* add a new gp-datablock */
+bGPdata *BKE_gpencil_data_addnew(Main *bmain, const char name[])
 {
-	bGPDbrush *brush;
-	/* Basic brush */
-	brush = BKE_gpencil_brush_addnew(ts, "Basic", true);
-	brush->thickness = 3.0f;
-	brush->flag &= ~GP_BRUSH_USE_RANDOM_PRESSURE;
-	brush->draw_sensitivity = 1.0f;
-	brush->flag |= GP_BRUSH_USE_PRESSURE;
-
-	brush->flag &= ~GP_BRUSH_USE_RANDOM_STRENGTH;
-	brush->draw_strength = 1.0f;
-	brush->flag |= ~GP_BRUSH_USE_STENGTH_PRESSURE;
-
-	brush->draw_random_press = 0.0f;
-
-	brush->draw_jitter = 0.0f;
-	brush->flag |= GP_BRUSH_USE_JITTER_PRESSURE;
-
-	brush->draw_angle = 0.0f;
-	brush->draw_angle_factor = 0.0f;
-
-	brush->draw_smoothfac = 0.0f;
-	brush->draw_smoothlvl = 1;
-	brush->sublevel = 0;
-	brush->draw_random_sub = 0.0f;
-
-	/* Pencil brush */
-	brush = BKE_gpencil_brush_addnew(ts, "Pencil", false);
-	brush->thickness = 7.0f;
-	brush->flag &= ~GP_BRUSH_USE_RANDOM_PRESSURE;
-	brush->draw_sensitivity = 1.0f;
-	brush->flag |= GP_BRUSH_USE_PRESSURE;
-
-	brush->flag &= ~GP_BRUSH_USE_RANDOM_STRENGTH;
-	brush->draw_strength = 0.7f;
-	brush->flag |= GP_BRUSH_USE_STENGTH_PRESSURE;
-
-	brush->draw_random_press = 0.0f;
-
-	brush->draw_jitter = 0.0f;
-	brush->flag |= GP_BRUSH_USE_JITTER_PRESSURE;
-
-	brush->draw_angle = 0.0f;
-	brush->draw_angle_factor = 0.0f;
-
-	brush->draw_smoothfac = 1.0f;
-	brush->draw_smoothlvl = 2;
-	brush->sublevel = 2;
-	brush->draw_random_sub = 0.0f;
-
-	/* Ink brush */
-	brush = BKE_gpencil_brush_addnew(ts, "Ink", false);
-	brush->thickness = 7.0f;
-	brush->flag &= ~GP_BRUSH_USE_RANDOM_PRESSURE;
-	brush->draw_sensitivity = 1.6f;
-	brush->flag |= GP_BRUSH_USE_PRESSURE;
-
-	brush->flag &= ~GP_BRUSH_USE_RANDOM_STRENGTH;
-	brush->draw_strength = 1.0f;
-	brush->flag &= ~GP_BRUSH_USE_STENGTH_PRESSURE;
-
-	brush->draw_random_press = 0.0f;
-
-	brush->draw_jitter = 0.0f;
-	brush->flag |= GP_BRUSH_USE_JITTER_PRESSURE;
-
-	brush->draw_angle = 0.0f;
-	brush->draw_angle_factor = 0.0f;
+	bGPdata *gpd;
 
-	brush->draw_smoothfac = 1.1f;
-	brush->draw_smoothlvl = 2;
-	brush->sublevel = 2;
-	brush->draw_random_sub = 0.0f;
+	/* allocate memory for a new block */
+	gpd = BKE_libblock_alloc(bmain, ID_GD, name, 0);
 
-	/* Ink Noise brush */
-	brush = BKE_gpencil_brush_addnew(ts, "Ink noise", false);
-	brush->thickness = 6.0f;
-	brush->flag |= GP_BRUSH_USE_RANDOM_PRESSURE;
-	brush->draw_sensitivity = 1.611f;
-	brush->flag |= GP_BRUSH_USE_PRESSURE;
+	/* initial settings */
+	gpd->flag = (GP_DATA_DISPINFO | GP_DATA_EXPAND);
 
-	brush->flag &= ~GP_BRUSH_USE_RANDOM_STRENGTH;
-	brush->draw_strength = 1.0f;
-	brush->flag |= GP_BRUSH_USE_STENGTH_PRESSURE;
+	/* general flags */
+	gpd->flag |= GP_DATA_VIEWALIGN;
 
-	brush->draw_random_press = 1.0f;
+	/* GP object specific settings */
+	ARRAY_SET_ITEMS(gpd->line_color, 0.6f, 0.6f, 0.6f, 0.5f);
 
-	brush->draw_jitter = 0.0f;
-	brush->flag |= GP_BRUSH_USE_JITTER_PRESSURE;
+	gpd->xray_mode = GP_XRAY_3DSPACE;
+	gpd->runtime.batch_cache_data = NULL;
+	gpd->pixfactor = GP_DEFAULT_PIX_FACTOR;
 
-	brush->draw_angle = 0.0f;
-	brush->draw_angle_factor = 0.0f;
+	/* onion-skinning settings (datablock level) */
+	gpd->onion_flag |= (GP_ONION_GHOST_PREVCOL | GP_ONION_GHOST_NEXTCOL);
+	gpd->onion_flag |= GP_ONION_FADE;
+	gpd->onion_mode = GP_ONION_MODE_RELATIVE;
+	gpd->onion_factor = 0.5f;
+	ARRAY_SET_ITEMS(gpd->gcolor_prev, 0.145098f, 0.419608f, 0.137255f); /* green */
+	ARRAY_SET_ITEMS(gpd->gcolor_next, 0.125490f, 0.082353f, 0.529412f); /* blue */
+	gpd->gstep = 1;
+	gpd->gstep_next = 1;
 
-	brush->draw_smoothfac = 1.1f;
-	brush->draw_smoothlvl = 2;
-	brush->sublevel = 2;
-	brush->draw_random_sub = 0.0f;
+	return gpd;
+}
 
-	/* Marker brush */
-	brush = BKE_gpencil_brush_addnew(ts, "Marker", false);
-	brush->thickness = 10.0f;
-	brush->flag &= ~GP_BRUSH_USE_RANDOM_PRESSURE;
-	brush->draw_sensitivity = 2.0f;
-	brush->flag &= ~GP_BRUSH_USE_PRESSURE;
 
-	brush->flag &= ~GP_BRUSH_USE_RANDOM_STRENGTH;
-	brush->draw_strength = 1.0f;
-	brush->flag &= ~GP_BRUSH_USE_STENGTH_PRESSURE;
+/* ************************************************** */
+/* Primitive Creation */
+/* Utilities for easier bulk-creation of geometry */
 
-	brush->draw_random_press = 0.0f;
+/**
+ * Populate stroke with point data from data buffers
+ *
+ * \param array Flat array of point data values. Each entry has GP_PRIM_DATABUF_SIZE values
+ * \param mat   4x4 transform matrix to transform points into the right coordinate space
+ */
+void BKE_gpencil_stroke_add_points(bGPDstroke *gps, const float *array, const int totpoints, const float mat[4][4])
+{
+	for (int i = 0; i < totpoints; i++) {
+		bGPDspoint *pt = &gps->points[i];
+		const int x = GP_PRIM_DATABUF_SIZE * i;
 
-	brush->draw_jitter = 0.0f;
-	brush->flag |= GP_BRUSH_USE_JITTER_PRESSURE;
+		pt->x = array[x];
+		pt->y = array[x + 1];
+		pt->z = array[x + 2];
+		mul_m4_v3(mat, &pt->x);
 
-	brush->draw_angle = M_PI_4; /* 45 degrees */
-	brush->draw_angle_factor = 1.0f;
+		pt->pressure = array[x + 3];
+		pt->strength = array[x + 4];
+	}
+}
 
-	brush->draw_smoothfac = 1.0f;
-	brush->draw_smoothlvl = 2;
-	brush->sublevel = 2;
-	brush->draw_random_sub = 0.0f;
+/* Create a new stroke, with pre-allocated data buffers */
+bGPDstroke *BKE_gpencil_add_stroke(bGPDframe *gpf, int mat_idx, int totpoints, short thickness)
+{
+	/* allocate memory for a new stroke */
+	bGPDstroke *gps = MEM_callocN(sizeof(bGPDstroke), "gp_stroke");
 
-	/* Crayon brush */
-	brush = BKE_gpencil_brush_addnew(ts, "Crayon", false);
-	brush->thickness = 10.0f;
-	brush->flag &= ~GP_BRUSH_USE_RANDOM_PRESSURE;
-	brush->draw_sensitivity = 3.0f;
-	brush->flag &= ~GP_BRUSH_USE_PRESSURE;
+	gps->thickness = thickness * 25;
+	gps->inittime = 0;
 
-	brush->flag &= ~GP_BRUSH_USE_RANDOM_STRENGTH;
-	brush->draw_strength = 0.140f;
-	brush->flag |= GP_BRUSH_USE_STENGTH_PRESSURE;
+	/* enable recalculation flag by default */
+	gps->flag = GP_STROKE_RECALC_CACHES | GP_STROKE_3DSPACE;
 
-	brush->draw_random_press = 0.0f;
+	gps->totpoints = totpoints;
+	gps->points = MEM_callocN(sizeof(bGPDspoint) * gps->totpoints, "gp_stroke_points");
+	gps->dvert = MEM_callocN(sizeof(MDeformVert) * gps->totpoints, "gp_stroke_weights");
 
-	brush->draw_jitter = 0.0f;
-	brush->flag |= GP_BRUSH_USE_JITTER_PRESSURE;
+	/* initialize triangle memory to dummy data */
+	gps->triangles = MEM_callocN(sizeof(bGPDtriangle), "GP Stroke triangulation");
+	gps->flag |= GP_STROKE_RECALC_CACHES;
+	gps->tot_triangles = 0;
 
-	brush->draw_angle = 0.0f;
-	brush->draw_angle_factor = 0.0f;
+	gps->mat_nr = mat_idx;
 
-	brush->draw_smoothfac = 0.0f;
-	brush->draw_smoothlvl = 1;
-	brush->sublevel = 2;
-	brush->draw_random_sub = 0.5f;
+	/* add to frame */
+	BLI_addtail(&gpf->strokes, gps);
 
+	return gps;
 }
 
-/* add a new gp-brush and make it the active */
-bGPDbrush *BKE_gpencil_brush_addnew(ToolSettings *ts, const char *name, bool setactive)
-{
-	bGPDbrush *brush;
-
-	/* check that list is ok */
-	if (ts == NULL) {
-		return NULL;
-	}
-
-	/* allocate memory and add to end of list */
-	brush = MEM_callocN(sizeof(bGPDbrush), "bGPDbrush");
 
-	/* add to datablock */
-	BLI_addtail(&ts->gp_brushes, brush);
-
-	/* set basic settings */
-	brush->thickness = 3;
-	brush->draw_smoothlvl = 1;
-	brush->flag |= GP_BRUSH_USE_PRESSURE;
-	brush->draw_sensitivity = 1.0f;
-	brush->draw_strength = 1.0f;
-	brush->flag |= GP_BRUSH_USE_STENGTH_PRESSURE;
-	brush->draw_jitter = 0.0f;
-	brush->flag |= GP_BRUSH_USE_JITTER_PRESSURE;
-
-	/* curves */
-	brush->cur_sensitivity = curvemapping_add(1, 0.0f, 0.0f, 1.0f, 1.0f);
-	brush->cur_strength = curvemapping_add(1, 0.0f, 0.0f, 1.0f, 1.0f);
-	brush->cur_jitter = curvemapping_add(1, 0.0f, 0.0f, 1.0f, 1.0f);
-
-	/* auto-name */
-	BLI_strncpy(brush->info, name, sizeof(brush->info));
-	BLI_uniquename(&ts->gp_brushes, brush, DATA_("GP_Brush"), '.', offsetof(bGPDbrush, info), sizeof(brush->info));
-
-	/* make this one the active one */
-	if (setactive) {
-		BKE_gpencil_brush_setactive(ts, brush);
-	}
-
-	/* return brush */
-	return brush;
-}
+/* ************************************************** */
+/* Data Duplication */
 
-/* add a new gp-palettecolor and make it the active */
-bGPDpalettecolor *BKE_gpencil_palettecolor_addnew(bGPDpalette *palette, const char *name, bool setactive)
+/* make a copy of a given gpencil weights */
+void BKE_gpencil_stroke_weights_duplicate(bGPDstroke *gps_src, bGPDstroke *gps_dst)
 {
-	bGPDpalettecolor *palcolor;
-
-	/* check that list is ok */
-	if (palette == NULL) {
-		return NULL;
+	if (gps_src == NULL) {
+		return;
 	}
+	BLI_assert(gps_src->totpoints == gps_dst->totpoints);
 
-	/* allocate memory and add to end of list */
-	palcolor = MEM_callocN(sizeof(bGPDpalettecolor), "bGPDpalettecolor");
-
-	/* add to datablock */
-	BLI_addtail(&palette->colors, palcolor);
-
-	/* set basic settings */
-	palcolor->flag |= PC_COLOR_HQ_FILL;
-	copy_v4_v4(palcolor->color, U.gpencil_new_layer_col);
-	ARRAY_SET_ITEMS(palcolor->fill, 1.0f, 1.0f, 1.0f);
+	if ((gps_src->dvert == NULL) || (gps_dst->dvert == NULL)){
+		return;
+	}
 
-	/* auto-name */
-	BLI_strncpy(palcolor->info, name, sizeof(palcolor->info));
-	BLI_uniquename(&palette->colors, palcolor, DATA_("Color"), '.', offsetof(bGPDpalettecolor, info),
-	               sizeof(palcolor->info));
+	for (int i = 0; i < gps_src->totpoints; i++) {
+		MDeformVert *dvert_src = &gps_src->dvert[i];
+		MDeformVert *dvert_dst = &gps_dst->dvert[i];
+		if (dvert_src->totweight > 0) {
+			dvert_dst->dw = MEM_dupallocN(dvert_src->dw);
+		}
+		else {
+			dvert_dst->dw = NULL;
+		}
 
-	/* make this one the active one */
-	if (setactive) {
-		BKE_gpencil_palettecolor_setactive(palette, palcolor);
 	}
-
-	/* return palette color */
-	return palcolor;
 }
 
-/* add a new gp-datablock */
-bGPdata *BKE_gpencil_data_addnew(Main *bmain, const char name[])
+/* make a copy of a given gpencil stroke */
+bGPDstroke *BKE_gpencil_stroke_duplicate(bGPDstroke *gps_src)
 {
-	bGPdata *gpd;
+	bGPDstroke *gps_dst = NULL;
 
-	/* allocate memory for a new block */
-	gpd = BKE_libblock_alloc(bmain, ID_GD, name, 0);
+	gps_dst = MEM_dupallocN(gps_src);
+	gps_dst->prev = gps_dst->next = NULL;
 
-	/* initial settings */
-	gpd->flag = (GP_DATA_DISPINFO | GP_DATA_EXPAND);
+	gps_dst->points = MEM_dupallocN(gps_src->points);
 
-	/* for now, stick to view is also enabled by default
-	 * since this is more useful...
+	gps_dst->dvert = MEM_dupallocN(gps_src->dvert);
+	BKE_gpencil_stroke_weights_duplicate(gps_src, gps_dst);
+
+	/* Don't clear triangles, so that modifier evaluation can just use
+	 * this without extra work first. Most places that need to force
+	 * this data to get recalculated will destroy the data anyway though.
 	 */
-	gpd->flag |= GP_DATA_VIEWALIGN;
+	gps_dst->triangles = MEM_dupallocN(gps_dst->triangles);
+	/* gps_dst->flag |= GP_STROKE_RECALC_CACHES; */
 
-	return gpd;
+	/* return new stroke */
+	return gps_dst;
 }
 
-/* -------- Data Duplication ---------- */
-
 /* make a copy of a given gpencil frame */
 bGPDframe *BKE_gpencil_frame_duplicate(const bGPDframe *gpf_src)
 {
-	bGPDstroke *gps_dst;
+	bGPDstroke *gps_dst = NULL;
 	bGPDframe *gpf_dst;
 
 	/* error checking */
@@ -660,11 +605,8 @@ bGPDframe *BKE_gpencil_frame_duplicate(const bGPDframe *gpf_src)
 	/* copy strokes */
 	BLI_listbase_clear(&gpf_dst->strokes);
 	for (bGPDstroke *gps_src = gpf_src->strokes.first; gps_src; gps_src = gps_src->next) {
-		/* make copy of source stroke, then adjust pointer to points too */
-		gps_dst = MEM_dupallocN(gps_src);
-		gps_dst->points = MEM_dupallocN(gps_src->points);
-		gps_dst->triangles = MEM_dupallocN(gps_src->triangles);
-		gps_dst->flag |= GP_STROKE_RECALC_CACHES;
+		/* make copy of source stroke */
+		gps_dst = BKE_gpencil_stroke_duplicate(gps_src);
 		BLI_addtail(&gpf_dst->strokes, gps_dst);
 	}
 
@@ -672,55 +614,24 @@ bGPDframe *BKE_gpencil_frame_duplicate(const bGPDframe *gpf_src)
 	return gpf_dst;
 }
 
-/* make a copy of a given gpencil brush */
-bGPDbrush *BKE_gpencil_brush_duplicate(const bGPDbrush *brush_src)
+/* make a copy of strokes between gpencil frames */
+void BKE_gpencil_frame_copy_strokes(bGPDframe *gpf_src, struct bGPDframe *gpf_dst)
 {
-	bGPDbrush *brush_dst;
-
+	bGPDstroke *gps_dst = NULL;
 	/* error checking */
-	if (brush_src == NULL) {
-		return NULL;
-	}
-
-	/* make a copy of source brush */
-	brush_dst = MEM_dupallocN(brush_src);
-	brush_dst->prev = brush_dst->next = NULL;
-	/* make a copy of curves */
-	brush_dst->cur_sensitivity = curvemapping_copy(brush_src->cur_sensitivity);
-	brush_dst->cur_strength = curvemapping_copy(brush_src->cur_strength);
-	brush_dst->cur_jitter = curvemapping_copy(brush_src->cur_jitter);
-
-	/* return new brush */
-	return brush_dst;
-}
-
-/* make a copy of a given gpencil palette */
-bGPDpalette *BKE_gpencil_palette_duplicate(const bGPDpalette *palette_src)
-{
-	bGPDpalette *palette_dst;
-	const bGPDpalettecolor *palcolor_src;
-	bGPDpalettecolor *palcolord_dst;
-
-	/* error checking */
-	if (palette_src == NULL) {
-		return NULL;
+	if ((gpf_src == NULL) || (gpf_dst == NULL)) {
+		return;
 	}
 
-	/* make a copy of source palette */
-	palette_dst = MEM_dupallocN(palette_src);
-	palette_dst->prev = palette_dst->next = NULL;
-
-	/* copy colors */
-	BLI_listbase_clear(&palette_dst->colors);
-	for (palcolor_src = palette_src->colors.first; palcolor_src; palcolor_src = palcolor_src->next) {
-		/* make a copy of source */
-		palcolord_dst = MEM_dupallocN(palcolor_src);
-		BLI_addtail(&palette_dst->colors, palcolord_dst);
+	/* copy strokes */
+	BLI_listbase_clear(&gpf_dst->strokes);
+	for (bGPDstroke *gps_src = gpf_src->strokes.first; gps_src; gps_src = gps_src->next) {
+		/* make copy of source stroke */
+		gps_dst = BKE_gpencil_stroke_duplicate(gps_src);
+		BLI_addtail(&gpf_dst->strokes, gps_dst);
 	}
-
-	/* return new palette */
-	return palette_dst;
 }
+
 /* make a copy of a given gpencil layer */
 bGPDlayer *BKE_gpencil_layer_duplicate(const bGPDlayer *gpl_src)
 {
@@ -736,6 +647,7 @@ bGPDlayer *BKE_gpencil_layer_duplicate(const bGPDlayer *gpl_src)
 	/* make a copy of source layer */
 	gpl_dst = MEM_dupallocN(gpl_src);
 	gpl_dst->prev = gpl_dst->next = NULL;
+	gpl_dst->runtime.derived_data = NULL;
 
 	/* copy frames */
 	BLI_listbase_clear(&gpl_dst->frames);
@@ -755,7 +667,7 @@ bGPDlayer *BKE_gpencil_layer_duplicate(const bGPDlayer *gpl_src)
 
 /**
  * Only copy internal data of GreasePencil ID from source to already allocated/initialized destination.
- * You probably nerver want to use that directly, use id_copy or BKE_id_copy_ex for typical needs.
+ * You probably never want to use that directly, use id_copy or BKE_id_copy_ex for typical needs.
  *
  * WARNING! This function will not handle ID user count!
  *
@@ -763,6 +675,14 @@ bGPDlayer *BKE_gpencil_layer_duplicate(const bGPDlayer *gpl_src)
  */
 void BKE_gpencil_copy_data(Main *UNUSED(bmain), bGPdata *gpd_dst, const bGPdata *gpd_src, const int UNUSED(flag))
 {
+	/* cache data is not duplicated */
+	gpd_dst->runtime.batch_cache_data = NULL;
+
+	/* duplicate material array */
+	if (gpd_src->mat) {
+		gpd_dst->mat = MEM_dupallocN(gpd_src->mat);
+	}
+
 	/* copy layers */
 	BLI_listbase_clear(&gpd_dst->layers);
 	for (const bGPDlayer *gpl_src = gpd_src->layers.first; gpl_src; gpl_src = gpl_src->next) {
@@ -771,45 +691,46 @@ void BKE_gpencil_copy_data(Main *UNUSED(bmain), bGPdata *gpd_dst, const bGPdata
 		BLI_addtail(&gpd_dst->layers, gpl_dst);
 	}
 
-	/* copy palettes */
-	BLI_listbase_clear(&gpd_dst->palettes);
-	for (const bGPDpalette *palette_src = gpd_src->palettes.first; palette_src; palette_src = palette_src->next) {
-		bGPDpalette *palette_dst = BKE_gpencil_palette_duplicate(palette_src);  /* TODO here too could add unused flags... */
-		BLI_addtail(&gpd_dst->palettes, palette_dst);
-	}
+}
+
+/* Standard API to make a copy of GP datablock, separate from copying its data */
+bGPdata *BKE_gpencil_copy(Main *bmain, const bGPdata *gpd)
+{
+	bGPdata *gpd_copy;
+	BKE_id_copy_ex(bmain, &gpd->id, (ID **)&gpd_copy, 0, false);
+	return gpd_copy;
 }
 
 /* make a copy of a given gpencil datablock */
+// XXX: Should this be deprecated?
 bGPdata *BKE_gpencil_data_duplicate(Main *bmain, const bGPdata *gpd_src, bool internal_copy)
 {
+	bGPdata *gpd_dst;
+
 	/* Yuck and super-uber-hyper yuck!!!
 	 * Should be replaceable with a no-main copy (LIB_ID_COPY_NO_MAIN etc.), but not sure about it,
 	 * so for now keep old code for that one. */
-	if (internal_copy) {
-		const bGPDlayer *gpl_src;
-		bGPDlayer *gpl_dst;
-		bGPdata *gpd_dst;
 
+	/* error checking */
+	if (gpd_src == NULL) {
+		return NULL;
+	}
+
+	if (internal_copy) {
 		/* make a straight copy for undo buffers used during stroke drawing */
 		gpd_dst = MEM_dupallocN(gpd_src);
-
-		/* copy layers */
-		BLI_listbase_clear(&gpd_dst->layers);
-		for (gpl_src = gpd_src->layers.first; gpl_src; gpl_src = gpl_src->next) {
-			/* make a copy of source layer and its data */
-			gpl_dst = BKE_gpencil_layer_duplicate(gpl_src);
-			BLI_addtail(&gpd_dst->layers, gpl_dst);
-		}
-
-		/* return new */
-		return gpd_dst;
 	}
 	else {
 		BLI_assert(bmain != NULL);
-		bGPdata *gpd_copy;
-		BKE_id_copy_ex(bmain, &gpd_src->id, (ID **)&gpd_copy, 0, false);
-		return gpd_copy;
+		BKE_id_copy_ex(bmain, &gpd_src->id, (ID **)&gpd_dst, 0, false);
+		gpd_dst->runtime.batch_cache_data = NULL;
 	}
+
+	/* Copy internal data (layers, etc.) */
+	BKE_gpencil_copy_data(bmain, gpd_dst, gpd_src, 0);
+
+	/* return new */
+	return gpd_dst;
 }
 
 void BKE_gpencil_make_local(Main *bmain, bGPdata *gpd, const bool lib_local)
@@ -817,7 +738,8 @@ void BKE_gpencil_make_local(Main *bmain, bGPdata *gpd, const bool lib_local)
 	BKE_id_make_local_generic(bmain, &gpd->id, true, lib_local);
 }
 
-/* -------- GP-Stroke API --------- */
+/* ************************************************** */
+/* GP Stroke API */
 
 /* ensure selection status of stroke is in sync with its points */
 void BKE_gpencil_stroke_sync_selection(bGPDstroke *gps)
@@ -842,7 +764,8 @@ void BKE_gpencil_stroke_sync_selection(bGPDstroke *gps)
 	}
 }
 
-/* -------- GP-Frame API ---------- */
+/* ************************************************** */
+/* GP Frame API */
 
 /* delete the last stroke of the given frame */
 void BKE_gpencil_frame_delete_laststroke(bGPDlayer *gpl, bGPDframe *gpf)
@@ -855,7 +778,13 @@ void BKE_gpencil_frame_delete_laststroke(bGPDlayer *gpl, bGPDframe *gpf)
 		return;
 
 	/* free the stroke and its data */
-	MEM_freeN(gps->points);
+	if (gps->points) {
+		MEM_freeN(gps->points);
+	}
+	if (gps->dvert) {
+		BKE_gpencil_free_stroke_weights(gps);
+		MEM_freeN(gps->dvert);
+	}
 	MEM_freeN(gps->triangles);
 	BLI_freelinkN(&gpf->strokes, gps);
 
@@ -866,7 +795,8 @@ void BKE_gpencil_frame_delete_laststroke(bGPDlayer *gpl, bGPDframe *gpf)
 	}
 }
 
-/* -------- GP-Layer API ---------- */
+/* ************************************************** */
+/* GP Layer API */
 
 /* Check if the given layer is able to be edited or not */
 bool gpencil_layer_is_editable(const bGPDlayer *gpl)
@@ -1048,8 +978,6 @@ bool BKE_gpencil_layer_delframe(bGPDlayer *gpl, bGPDframe *gpf)
 	 */
 	if (gpl->actframe == gpf)
 		gpl->actframe = gpf->prev;
-	else
-		gpl->actframe = NULL;
 
 	/* free the frame and its data */
 	changed = BKE_gpencil_free_strokes(gpf);
@@ -1103,255 +1031,602 @@ void BKE_gpencil_layer_delete(bGPdata *gpd, bGPDlayer *gpl)
 
 	/* free layer */
 	BKE_gpencil_free_frames(gpl);
+
+	/* free icon providing preview of icon color */
+	BKE_icon_delete(gpl->runtime.icon_id);
+
+	/* free derived data */
+	BKE_gpencil_clear_derived(gpl);
+	if (gpl->runtime.derived_data) {
+		BLI_ghash_free(gpl->runtime.derived_data, NULL, NULL);
+		gpl->runtime.derived_data = NULL;
+	}
+
 	BLI_freelinkN(&gpd->layers, gpl);
 }
 
-/* ************************************************** */
-/* get the active gp-brush for editing */
-bGPDbrush *BKE_gpencil_brush_getactive(ToolSettings *ts)
+Material *BKE_gpencil_get_material_from_brush(Brush *brush)
 {
-	bGPDbrush *brush;
+	Material *ma = NULL;
 
-	/* error checking */
-	if (ELEM(NULL, ts, ts->gp_brushes.first)) {
-		return NULL;
+	if ((brush != NULL) && (brush->gpencil_settings != NULL) &&
+		(brush->gpencil_settings->material != NULL))
+	{
+		ma = brush->gpencil_settings->material;
 	}
 
-	/* loop over brushes until found (assume only one active) */
-	for (brush = ts->gp_brushes.first; brush; brush = brush->next) {
-		if (brush->flag & GP_BRUSH_ACTIVE) {
-			return brush;
+	return ma;
+}
+
+/* Get active color, and add all default settings if we don't find anything */
+Material *BKE_gpencil_material_ensure(Main *bmain, Object *ob)
+{
+	Material *ma = NULL;
+
+	/* sanity checks */
+	if (ELEM(NULL, bmain, ob))
+		return NULL;
+
+	ma = give_current_material(ob, ob->actcol);
+	if (ma == NULL) {
+		if (ob->totcol == 0) {
+			BKE_object_material_slot_add(bmain, ob);
 		}
+		ma = BKE_material_add_gpencil(bmain, DATA_("Material"));
+		assign_material(bmain, ob, ma, ob->totcol, BKE_MAT_ASSIGN_EXISTING);
+	}
+	else if (ma->gp_style == NULL) {
+			BKE_material_init_gpencil_settings(ma);
 	}
 
-	/* no active brush found */
-	return NULL;
+	return ma;
 }
 
-/* set the active gp-brush */
-void BKE_gpencil_brush_setactive(ToolSettings *ts, bGPDbrush *active)
+/* ************************************************** */
+/* GP Object - Boundbox Support */
+
+/**
+ * Get min/max coordinate bounds for single stroke
+ * \return Returns whether we found any selected points
+ */
+bool BKE_gpencil_stroke_minmax(
+        const bGPDstroke *gps, const bool use_select,
+        float r_min[3], float r_max[3])
 {
-	bGPDbrush *brush;
+	const bGPDspoint *pt;
+	int i;
+	bool changed = false;
 
-	/* error checking */
-	if (ELEM(NULL, ts, ts->gp_brushes.first, active)) {
-		return;
-	}
+	if (ELEM(NULL, gps, r_min, r_max))
+		return false;
 
-	/* loop over brushes deactivating all */
-	for (brush = ts->gp_brushes.first; brush; brush = brush->next) {
-		brush->flag &= ~GP_BRUSH_ACTIVE;
+	for (i = 0, pt = gps->points; i < gps->totpoints; i++, pt++) {
+		if ((use_select == false) || (pt->flag & GP_SPOINT_SELECT)) {
+			minmax_v3v3_v3(r_min, r_max, &pt->x);
+			changed = true;
+		}
 	}
-
-	/* set as active one */
-	active->flag |= GP_BRUSH_ACTIVE;
+	return changed;
 }
 
-/* delete the active gp-brush */
-void BKE_gpencil_brush_delete(ToolSettings *ts, bGPDbrush *brush)
+/* get min/max bounds of all strokes in GP datablock */
+static void gpencil_minmax(bGPdata *gpd, float r_min[3], float r_max[3])
 {
-	/* error checking */
-	if (ELEM(NULL, ts, brush)) {
+	INIT_MINMAX(r_min, r_max);
+
+	if (gpd == NULL)
 		return;
-	}
 
-	/* free curves */
-	if (brush->cur_sensitivity) {
-		curvemapping_free(brush->cur_sensitivity);
-	}
-	if (brush->cur_strength) {
-		curvemapping_free(brush->cur_strength);
+	for (bGPDlayer *gpl = gpd->layers.first; gpl; gpl = gpl->next) {
+		bGPDframe *gpf = gpl->actframe;
+
+		if (gpf != NULL) {
+			for (bGPDstroke *gps = gpf->strokes.first; gps; gps = gps->next) {
+				BKE_gpencil_stroke_minmax(gps, false, r_min, r_max);
+			}
+		}
 	}
-	if (brush->cur_jitter) {
-		curvemapping_free(brush->cur_jitter);
+}
+
+/* compute center of bounding box */
+void BKE_gpencil_centroid_3D(bGPdata *gpd, float r_centroid[3])
+{
+	float min[3], max[3], tot[3];
+
+	gpencil_minmax(gpd, min, max);
+
+	add_v3_v3v3(tot, min, max);
+	mul_v3_v3fl(r_centroid, tot, 0.5f);
+}
+
+
+/* create bounding box values */
+static void boundbox_gpencil(Object *ob)
+{
+	BoundBox *bb;
+	bGPdata *gpd;
+	float min[3], max[3];
+
+	if (ob->bb == NULL) {
+		ob->bb = MEM_callocN(sizeof(BoundBox), "GPencil boundbox");
 	}
 
-	/* free */
-	BLI_freelinkN(&ts->gp_brushes, brush);
+	bb  = ob->bb;
+	gpd = ob->data;
+
+	gpencil_minmax(gpd, min, max);
+	BKE_boundbox_init_from_minmax(bb, min, max);
+
+	bb->flag &= ~BOUNDBOX_DIRTY;
 }
 
-/* ************************************************** */
-/* get the active gp-palette for editing */
-bGPDpalette *BKE_gpencil_palette_getactive(bGPdata *gpd)
+/* get bounding box */
+BoundBox *BKE_gpencil_boundbox_get(Object *ob)
 {
-	bGPDpalette *palette;
+	bGPdata *gpd;
 
-	/* error checking */
-	if (ELEM(NULL, gpd, gpd->palettes.first)) {
+	if (ELEM(NULL, ob, ob->data))
 		return NULL;
-	}
 
-	/* loop over palettes until found (assume only one active) */
-	for (palette = gpd->palettes.first; palette; palette = palette->next) {
-		if (palette->flag & PL_PALETTE_ACTIVE)
-			return palette;
+	gpd = ob->data;
+	if ((ob->bb) && ((ob->bb->flag & BOUNDBOX_DIRTY) == 0) &&
+	    ((gpd->flag & GP_DATA_CACHE_IS_DIRTY) == 0))
+	{
+		return ob->bb;
 	}
 
-	/* no active palette found */
-	return NULL;
+	boundbox_gpencil(ob);
+
+	return ob->bb;
 }
 
-/* set the active gp-palette */
-void BKE_gpencil_palette_setactive(bGPdata *gpd, bGPDpalette *active)
-{
-	bGPDpalette *palette;
+/* ************************************************** */
+/* Apply Transforms */
 
-	/* error checking */
-	if (ELEM(NULL, gpd, gpd->palettes.first, active)) {
+void BKE_gpencil_transform(bGPdata *gpd, float mat[4][4])
+{
+	if (gpd == NULL)
 		return;
+
+	for (bGPDlayer *gpl = gpd->layers.first; gpl; gpl = gpl->next) {
+		/* FIXME: For now, we just skip parented layers.
+		 * Otherwise, we have to update each frame to find
+		 * the current parent position/effects.
+		 */
+		if (gpl->parent) {
+			continue;
+		}
+
+		for (bGPDframe *gpf = gpl->frames.first; gpf; gpf = gpf->next) {
+			for (bGPDstroke *gps = gpf->strokes.first; gps; gps = gps->next) {
+				bGPDspoint *pt;
+				int i;
+
+				for (pt = gps->points, i = 0; i < gps->totpoints; pt++, i++) {
+					mul_m4_v3(mat, &pt->x);
+				}
+
+				/* TODO: Do we need to do this? distortion may mean we need to re-triangulate */
+				gps->flag |= GP_STROKE_RECALC_CACHES;
+				gps->tot_triangles = 0;
+			}
+		}
 	}
 
-	/* loop over palettes deactivating all */
-	for (palette = gpd->palettes.first; palette; palette = palette->next) {
-		palette->flag &= ~PL_PALETTE_ACTIVE;
+}
+
+/* ************************************************** */
+/* GP Object - Vertex Groups */
+
+/* remove a vertex group */
+void BKE_gpencil_vgroup_remove(Object *ob, bDeformGroup *defgroup)
+{
+	bGPdata *gpd = ob->data;
+	MDeformVert *dvert = NULL;
+	MDeformWeight *gpw = NULL;
+	const int def_nr = BLI_findindex(&ob->defbase, defgroup);
+
+	/* Remove points data */
+	if (gpd) {
+		for (bGPDlayer *gpl = gpd->layers.first; gpl; gpl = gpl->next) {
+			for (bGPDframe *gpf = gpl->frames.first; gpf; gpf = gpf->next) {
+				for (bGPDstroke *gps = gpf->strokes.first; gps; gps = gps->next) {
+					for (int i = 0; i < gps->totpoints; i++) {
+						dvert = &gps->dvert[i];
+						for (int i2 = 0; i2 < dvert->totweight; i2++) {
+							gpw = &dvert->dw[i2];
+							if (gpw->def_nr == def_nr) {
+								BKE_gpencil_vgroup_remove_point_weight(dvert, def_nr);
+							}
+							/* if index is greater, must be moved one back */
+							if (gpw->def_nr > def_nr) {
+								gpw->def_nr--;
+							}
+						}
+					}
+				}
+			}
+		}
 	}
 
-	/* set as active one */
-	active->flag |= PL_PALETTE_ACTIVE;
-	/* force color recalc */
-	BKE_gpencil_palette_change_strokes(gpd);
+	/* Remove the group */
+	BLI_freelinkN(&ob->defbase, defgroup);
 }
 
-/* delete the active gp-palette */
-void BKE_gpencil_palette_delete(bGPdata *gpd, bGPDpalette *palette)
+/* add a new weight */
+MDeformWeight *BKE_gpencil_vgroup_add_point_weight(MDeformVert *dvert, int index, float weight)
 {
-	/* error checking */
-	if (ELEM(NULL, gpd, palette)) {
-		return;
+	MDeformWeight *new_gpw = NULL;
+	MDeformWeight *tmp_gpw;
+
+	/* need to verify if was used before to update */
+	for (int i = 0; i < dvert->totweight; i++) {
+		tmp_gpw = &dvert->dw[i];
+		if (tmp_gpw->def_nr == index) {
+			tmp_gpw->weight = weight;
+			return tmp_gpw;
+		}
+	}
+
+	dvert->totweight++;
+	if (dvert->totweight == 1) {
+		dvert->dw = MEM_callocN(sizeof(MDeformWeight), "gp_weight");
+	}
+	else {
+		dvert->dw = MEM_reallocN(dvert->dw, sizeof(MDeformWeight) * dvert->totweight);
 	}
+	new_gpw = &dvert->dw[dvert->totweight - 1];
+	new_gpw->def_nr = index;
+	new_gpw->weight = weight;
 
-	/* free colors */
-	free_gpencil_colors(palette);
-	BLI_freelinkN(&gpd->palettes, palette);
-	/* force color recalc */
-	BKE_gpencil_palette_change_strokes(gpd);
+	return new_gpw;
 }
 
-/* Set all strokes to recalc the palette color */
-void BKE_gpencil_palette_change_strokes(bGPdata *gpd)
+/* return the weight if use index  or -1*/
+float BKE_gpencil_vgroup_use_index(MDeformVert *dvert, int index)
 {
-	bGPDlayer *gpl;
-	bGPDframe *gpf;
-	bGPDstroke *gps;
+	MDeformWeight *gpw;
+	for (int i = 0; i < dvert->totweight; i++) {
+		gpw = &dvert->dw[i];
+		if (gpw->def_nr == index) {
+			return gpw->weight;
+		}
+	}
+	return -1.0f;
+}
 
-	for (gpl = gpd->layers.first; gpl; gpl = gpl->next) {
-		for (gpf = gpl->frames.first; gpf; gpf = gpf->next) {
-			for (gps = gpf->strokes.first; gps; gps = gps->next) {
-				gps->flag |= GP_STROKE_RECALC_COLOR;
-			}
+/* add a new weight */
+bool BKE_gpencil_vgroup_remove_point_weight(MDeformVert *dvert, int index)
+{
+	int e = 0;
+
+	if (BKE_gpencil_vgroup_use_index(dvert, index) < 0.0f) {
+		return false;
+	}
+
+	/* if the array get empty, exit */
+	if (dvert->totweight == 1) {
+		dvert->totweight = 0;
+		MEM_SAFE_FREE(dvert->dw);
+		return true;
+	}
+
+	/* realloc weights */
+	MDeformWeight *tmp = MEM_dupallocN(dvert->dw);
+	MEM_SAFE_FREE(dvert->dw);
+	dvert->dw = MEM_callocN(sizeof(MDeformWeight) * dvert->totweight - 1, "gp_weights");
+
+	for (int x = 0; x < dvert->totweight; x++) {
+		MDeformWeight *gpw = &tmp[e];
+		MDeformWeight *final_gpw = &dvert->dw[e];
+		if (gpw->def_nr != index) {
+			final_gpw->def_nr = gpw->def_nr;
+			final_gpw->weight = gpw->weight;
+			e++;
 		}
 	}
+	MEM_SAFE_FREE(tmp);
+	dvert->totweight--;
+
+	return true;
 }
 
 
-/* get the active gp-palettecolor for editing */
-bGPDpalettecolor *BKE_gpencil_palettecolor_getactive(bGPDpalette *palette)
+/* ************************************************** */
+
+/**
+ * Apply smooth to stroke point
+ * \param gps              Stroke to smooth
+ * \param i                Point index
+ * \param inf              Amount of smoothing to apply
+ */
+bool BKE_gpencil_smooth_stroke(bGPDstroke *gps, int i, float inf)
 {
-	bGPDpalettecolor *palcolor;
+	bGPDspoint *pt = &gps->points[i];
+	// float pressure = 0.0f;
+	float sco[3] = { 0.0f };
 
-	/* error checking */
-	if (ELEM(NULL, palette, palette->colors.first)) {
-		return NULL;
+	/* Do nothing if not enough points to smooth out */
+	if (gps->totpoints <= 2) {
+		return false;
+	}
+
+	/* Only affect endpoints by a fraction of the normal strength,
+	* to prevent the stroke from shrinking too much
+	*/
+	if ((i == 0) || (i == gps->totpoints - 1)) {
+		inf *= 0.1f;
 	}
 
-	/* loop over colors until found (assume only one active) */
-	for (palcolor = palette->colors.first; palcolor; palcolor = palcolor->next) {
-		if (palcolor->flag & PC_COLOR_ACTIVE) {
-			return palcolor;
+	/* Compute smoothed coordinate by taking the ones nearby */
+	/* XXX: This is potentially slow, and suffers from accumulation error as earlier points are handled before later ones */
+	{
+		// XXX: this is hardcoded to look at 2 points on either side of the current one (i.e. 5 items total)
+		const int   steps = 2;
+		const float average_fac = 1.0f / (float)(steps * 2 + 1);
+		int step;
+
+		/* add the point itself */
+		madd_v3_v3fl(sco, &pt->x, average_fac);
+
+		/* n-steps before/after current point */
+		// XXX: review how the endpoints are treated by this algorithm
+		// XXX: falloff measures should also introduce some weighting variations, so that further-out points get less weight
+		for (step = 1; step <= steps; step++) {
+			bGPDspoint *pt1, *pt2;
+			int before = i - step;
+			int after = i + step;
+
+			CLAMP_MIN(before, 0);
+			CLAMP_MAX(after, gps->totpoints - 1);
+
+			pt1 = &gps->points[before];
+			pt2 = &gps->points[after];
+
+			/* add both these points to the average-sum (s += p[i]/n) */
+			madd_v3_v3fl(sco, &pt1->x, average_fac);
+			madd_v3_v3fl(sco, &pt2->x, average_fac);
+
 		}
 	}
 
-	/* no active color found */
-	return NULL;
+	/* Based on influence factor, blend between original and optimal smoothed coordinate */
+	interp_v3_v3v3(&pt->x, &pt->x, sco, inf);
+
+	return true;
 }
-/* get the gp-palettecolor looking for name */
-bGPDpalettecolor *BKE_gpencil_palettecolor_getbyname(bGPDpalette *palette, char *name)
+
+/**
+ * Apply smooth for strength to stroke point */
+bool BKE_gpencil_smooth_stroke_strength(bGPDstroke *gps, int point_index, float influence)
 {
-	/* error checking */
-	if (ELEM(NULL, palette, name)) {
-		return NULL;
+	bGPDspoint *ptb = &gps->points[point_index];
+
+	/* Do nothing if not enough points */
+	if (gps->totpoints <= 2) {
+		return false;
 	}
 
-	return BLI_findstring(&palette->colors, name, offsetof(bGPDpalettecolor, info));
+	/* Compute theoretical optimal value using distances */
+	bGPDspoint *pta, *ptc;
+	int before = point_index - 1;
+	int after = point_index + 1;
+
+	CLAMP_MIN(before, 0);
+	CLAMP_MAX(after, gps->totpoints - 1);
+
+	pta = &gps->points[before];
+	ptc = &gps->points[after];
+
+	/* the optimal value is the corresponding to the interpolation of the strength
+	*  at the distance of point b
+	*/
+	const float fac = line_point_factor_v3(&ptb->x, &pta->x, &ptc->x);
+	const float optimal = (1.0f - fac) * pta->strength + fac * ptc->strength;
+
+	/* Based on influence factor, blend between original and optimal */
+	ptb->strength = (1.0f - influence) * ptb->strength + influence * optimal;
+
+	return true;
 }
 
-/* Change color name in all strokes */
-void BKE_gpencil_palettecolor_changename(bGPdata *gpd, char *oldname, const char *newname)
+/**
+ * Apply smooth for thickness to stroke point (use pressure) */
+bool BKE_gpencil_smooth_stroke_thickness(bGPDstroke *gps, int point_index, float influence)
 {
-	bGPDlayer *gpl;
-	bGPDframe *gpf;
-	bGPDstroke *gps;
+	bGPDspoint *ptb = &gps->points[point_index];
 
-	/* Sanity checks (gpd may not be set in the RNA pointers sometimes) */
-	if (ELEM(NULL, gpd, oldname, newname))
-		return;
+	/* Do nothing if not enough points */
+	if (gps->totpoints <= 2) {
+		return false;
+	}
 
-	for (gpl = gpd->layers.first; gpl; gpl = gpl->next) {
-		for (gpf = gpl->frames.first; gpf; gpf = gpf->next) {
-			for (gps = gpf->strokes.first; gps; gps = gps->next) {
-				if (STREQ(gps->colorname, oldname)) {
-					BLI_strncpy(gps->colorname, newname, sizeof(gps->colorname));
-				}
+	/* Compute theoretical optimal value using distances */
+	bGPDspoint *pta, *ptc;
+	int before = point_index - 1;
+	int after = point_index + 1;
+
+	CLAMP_MIN(before, 0);
+	CLAMP_MAX(after, gps->totpoints - 1);
+
+	pta = &gps->points[before];
+	ptc = &gps->points[after];
+
+	/* the optimal value is the corresponding to the interpolation of the pressure
+	*  at the distance of point b
+	*/
+	float fac = line_point_factor_v3(&ptb->x, &pta->x, &ptc->x);
+	float optimal = interpf(ptc->pressure, pta->pressure, fac);
+
+	/* Based on influence factor, blend between original and optimal */
+	ptb->pressure = interpf(optimal, ptb->pressure, influence);
+
+	return true;
+}
+
+/**
+* Apply smooth for UV rotation to stroke point (use pressure) */
+bool BKE_gpencil_smooth_stroke_uv(bGPDstroke *gps, int point_index, float influence)
+{
+	bGPDspoint *ptb = &gps->points[point_index];
+
+	/* Do nothing if not enough points */
+	if (gps->totpoints <= 2) {
+		return false;
+	}
+
+	/* Compute theoretical optimal value */
+	bGPDspoint *pta, *ptc;
+	int before = point_index - 1;
+	int after = point_index + 1;
+
+	CLAMP_MIN(before, 0);
+	CLAMP_MAX(after, gps->totpoints - 1);
+
+	pta = &gps->points[before];
+	ptc = &gps->points[after];
+
+	/* the optimal value is the corresponding to the interpolation of the pressure
+	*  at the distance of point b
+	*/
+	float fac = line_point_factor_v3(&ptb->x, &pta->x, &ptc->x);
+	float optimal = interpf(ptc->uv_rot, pta->uv_rot, fac);
+
+	/* Based on influence factor, blend between original and optimal */
+	ptb->uv_rot = interpf(optimal, ptb->uv_rot, influence);
+	CLAMP(ptb->uv_rot, -M_PI_2, M_PI_2);
+
+	return true;
+}
+
+/**
+ * Get range of selected frames in layer.
+ * Always the active frame is considered as selected, so if no more selected the range
+ * will be equal to the current active frame.
+ * \param gpl              Layer
+ * \param r_initframe      Number of first selected frame
+ * \param r_endframe       Number of last selected frame
+ */
+void BKE_gpencil_get_range_selected(bGPDlayer *gpl, int *r_initframe, int *r_endframe)
+{
+	*r_initframe = gpl->actframe->framenum;
+	*r_endframe = gpl->actframe->framenum;
+
+	for (bGPDframe *gpf = gpl->frames.first; gpf; gpf = gpf->next) {
+		if (gpf->flag & GP_FRAME_SELECT) {
+			if (gpf->framenum < *r_initframe) {
+				*r_initframe = gpf->framenum;
+			}
+			if (gpf->framenum > *r_endframe) {
+				*r_endframe = gpf->framenum;
 			}
 		}
 	}
+}
+
+/**
+ * Get Falloff factor base on frame range
+ * \param gpf          Frame
+ * \param actnum       Number of active frame in layer
+ * \param f_init       Number of first selected frame
+ * \param f_end        Number of last selected frame
+ * \param cur_falloff  Curve with falloff factors
+ */
+float BKE_gpencil_multiframe_falloff_calc(bGPDframe *gpf, int actnum, int f_init, int f_end, CurveMapping *cur_falloff)
+{
+	float fnum = 0.5f; /* default mid curve */
+	float value;
+
+	/* frames to the right of the active frame */
+	if (gpf->framenum < actnum) {
+		fnum = (float)(gpf->framenum - f_init) / (actnum - f_init);
+		fnum *= 0.5f;
+		value = curvemapping_evaluateF(cur_falloff, 0, fnum);
+	}
+	/* frames to the left of the active frame */
+	else if (gpf->framenum > actnum) {
+		fnum = (float)(gpf->framenum - actnum) / (f_end - actnum);
+		fnum *= 0.5f;
+		value = curvemapping_evaluateF(cur_falloff, 0, fnum + 0.5f);
+	}
+	else {
+		value = 1.0f;
+	}
 
+	return value;
 }
 
-/* Delete all strokes of the color */
-void BKE_gpencil_palettecolor_delete_strokes(struct bGPdata *gpd, char *name)
+/* remove strokes using a material */
+void BKE_gpencil_material_index_remove(bGPdata *gpd, int index)
 {
-	bGPDlayer *gpl;
-	bGPDframe *gpf;
 	bGPDstroke *gps, *gpsn;
 
-	/* Sanity checks (gpd may not be set in the RNA pointers sometimes) */
-	if (ELEM(NULL, gpd, name))
-		return;
-
-	for (gpl = gpd->layers.first; gpl; gpl = gpl->next) {
-		for (gpf = gpl->frames.first; gpf; gpf = gpf->next) {
-			for (gps = gpf->strokes.first; gps; gps = gpsn) {
-				gpsn = gps->next;
-
-				if (STREQ(gps->colorname, name)) {
-					if (gps->points) MEM_freeN(gps->points);
-					if (gps->triangles) MEM_freeN(gps->triangles);
-					BLI_freelinkN(&gpf->strokes, gps);
+		for (bGPDlayer *gpl = gpd->layers.first; gpl; gpl = gpl->next) {
+			for (bGPDframe *gpf = gpl->frames.first; gpf; gpf = gpf->next) {
+				for (gps = gpf->strokes.first; gps; gps = gpsn) {
+					gpsn = gps->next;
+					if (gps->mat_nr == index) {
+						if (gps->points) {
+							MEM_freeN(gps->points);
+						}
+						if (gps->dvert) {
+							BKE_gpencil_free_stroke_weights(gps);
+							MEM_freeN(gps->dvert);
+						}
+						if (gps->triangles) MEM_freeN(gps->triangles);
+						BLI_freelinkN(&gpf->strokes, gps);
+					}
+					else {
+						/* reassign strokes */
+						if (gps->mat_nr > index) {
+							gps->mat_nr--;
+						}
+					}
 				}
 			}
 		}
-	}
-
 }
 
-/* set the active gp-palettecolor */
-void BKE_gpencil_palettecolor_setactive(bGPDpalette *palette, bGPDpalettecolor *active)
+void BKE_gpencil_material_remap(struct bGPdata *gpd, const unsigned int *remap, unsigned int remap_len)
 {
-	bGPDpalettecolor *palcolor;
-
-	/* error checking */
-	if (ELEM(NULL, palette, palette->colors.first, active)) {
-		return;
+	const short remap_len_short = (short)remap_len;
+
+#define MAT_NR_REMAP(n) \
+	if (n < remap_len_short) { \
+		BLI_assert(n >= 0 && remap[n] < remap_len_short); \
+		n = remap[n]; \
+	} ((void)0)
+
+	for (bGPDlayer *gpl = gpd->layers.first; gpl; gpl = gpl->next) {
+		for (bGPDframe *gpf = gpl->frames.first; gpf; gpf = gpf->next) {
+			for (bGPDstroke *gps = gpf->strokes.first; gps; gps = gps->next) {
+				/* reassign strokes */
+				MAT_NR_REMAP(gps->mat_nr);
+			}
+		}
 	}
 
-	/* loop over colors deactivating all */
-	for (palcolor = palette->colors.first; palcolor; palcolor = palcolor->next) {
-		palcolor->flag &= ~PC_COLOR_ACTIVE;
-	}
+#undef MAT_NR_REMAP
 
-	/* set as active one */
-	active->flag |= PC_COLOR_ACTIVE;
 }
 
-/* delete the active gp-palettecolor */
-void BKE_gpencil_palettecolor_delete(bGPDpalette *palette, bGPDpalettecolor *palcolor)
+/* statistics functions */
+void BKE_gpencil_stats_update(bGPdata *gpd)
 {
-	/* error checking */
-	if (ELEM(NULL, palette, palcolor)) {
-		return;
+	gpd->totlayer = 0;
+	gpd->totframe = 0;
+	gpd->totstroke = 0;
+	gpd->totpoint = 0;
+
+	for (bGPDlayer *gpl = gpd->layers.first; gpl; gpl = gpl->next) {
+		gpd->totlayer++;
+		for (bGPDframe *gpf = gpl->frames.first; gpf; gpf = gpf->next) {
+			gpd->totframe++;
+			for (bGPDstroke *gps = gpf->strokes.first; gps; gps = gps->next) {
+				gpd->totstroke++;
+				gpd->totpoint += gps->totpoints;
+			}
+		}
 	}
 
-	/* free */
-	BLI_freelinkN(&palette->colors, palcolor);
 }
diff --git a/source/blender/blenkernel/intern/gpencil_modifier.c b/source/blender/blenkernel/intern/gpencil_modifier.c
new file mode 100644
index 00000000000..2ba738902a0
--- /dev/null
+++ b/source/blender/blenkernel/intern/gpencil_modifier.c
@@ -0,0 +1,679 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2017, Blender Foundation
+ * This is a new part of Blender
+ *
+ * Contributor(s): Antonio Vazquez
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file blender/blenkernel/intern/gpencil_modifier.c
+ *  \ingroup bke
+ */
+
+
+#include <stdio.h>
+
+#include "MEM_guardedalloc.h"
+
+#include "BLI_blenlib.h"
+#include "BLI_utildefines.h"
+#include "BLI_math_vector.h"
+#include "BLI_string_utils.h"
+
+#include "BLT_translation.h"
+
+#include "DNA_meshdata_types.h"
+#include "DNA_scene_types.h"
+#include "DNA_object_types.h"
+#include "DNA_gpencil_types.h"
+#include "DNA_gpencil_modifier_types.h"
+
+#include "BKE_global.h"
+#include "BKE_library.h"
+#include "BKE_library_query.h"
+#include "BKE_gpencil.h"
+#include "BKE_lattice.h"
+#include "BKE_gpencil_modifier.h"
+#include "BKE_object.h"
+
+#include "DEG_depsgraph.h"
+#include "DEG_depsgraph_query.h"
+
+#include "MOD_gpencil_modifiertypes.h"
+
+static GpencilModifierTypeInfo *modifier_gpencil_types[NUM_GREASEPENCIL_MODIFIER_TYPES] = { NULL };
+
+/* *************************************************** */
+/* Geometry Utilities */
+
+/* calculate stroke normal using some points */
+void BKE_gpencil_stroke_normal(const bGPDstroke *gps, float r_normal[3])
+{
+	if (gps->totpoints < 3) {
+		zero_v3(r_normal);
+		return;
+	}
+
+	bGPDspoint *points = gps->points;
+	int totpoints = gps->totpoints;
+
+	const bGPDspoint *pt0 = &points[0];
+	const bGPDspoint *pt1 = &points[1];
+	const bGPDspoint *pt3 = &points[(int)(totpoints * 0.75)];
+
+	float vec1[3];
+	float vec2[3];
+
+	/* initial vector (p0 -> p1) */
+	sub_v3_v3v3(vec1, &pt1->x, &pt0->x);
+
+	/* point vector at 3/4 */
+	sub_v3_v3v3(vec2, &pt3->x, &pt0->x);
+
+	/* vector orthogonal to polygon plane */
+	cross_v3_v3v3(r_normal, vec1, vec2);
+
+	/* Normalize vector */
+	normalize_v3(r_normal);
+}
+
+/* Get points of stroke always flat to view not affected by camera view or view position */
+static void gpencil_stroke_project_2d(const bGPDspoint *points, int totpoints, vec2f *points2d)
+{
+	const bGPDspoint *pt0 = &points[0];
+	const bGPDspoint *pt1 = &points[1];
+	const bGPDspoint *pt3 = &points[(int)(totpoints * 0.75)];
+
+	float locx[3];
+	float locy[3];
+	float loc3[3];
+	float normal[3];
+
+	/* local X axis (p0 -> p1) */
+	sub_v3_v3v3(locx, &pt1->x, &pt0->x);
+
+	/* point vector at 3/4 */
+	sub_v3_v3v3(loc3, &pt3->x, &pt0->x);
+
+	/* vector orthogonal to polygon plane */
+	cross_v3_v3v3(normal, locx, loc3);
+
+	/* local Y axis (cross to normal/x axis) */
+	cross_v3_v3v3(locy, normal, locx);
+
+	/* Normalize vectors */
+	normalize_v3(locx);
+	normalize_v3(locy);
+
+	/* Get all points in local space */
+	for (int i = 0; i < totpoints; i++) {
+		const bGPDspoint *pt = &points[i];
+		float loc[3];
+
+		/* Get local space using first point as origin */
+		sub_v3_v3v3(loc, &pt->x, &pt0->x);
+
+		vec2f *point = &points2d[i];
+		point->x = dot_v3v3(loc, locx);
+		point->y = dot_v3v3(loc, locy);
+	}
+
+}
+
+/* Stroke Simplify ------------------------------------- */
+
+/* Reduce a series of points to a simplified version, but
+ * maintains the general shape of the series
+ *
+ * Ramer - Douglas - Peucker algorithm
+ * by http ://en.wikipedia.org/wiki/Ramer-Douglas-Peucker_algorithm
+ */
+static void gpencil_rdp_stroke(bGPDstroke *gps, vec2f *points2d, float epsilon)
+{
+	vec2f *old_points2d = points2d;
+	int totpoints = gps->totpoints;
+	char *marked = NULL;
+	char work;
+
+	int start = 1;
+	int end = gps->totpoints - 2;
+
+	marked = MEM_callocN(totpoints, "GP marked array");
+	marked[start] = 1;
+	marked[end] = 1;
+
+	work = 1;
+	int totmarked = 0;
+	/* while still reducing */
+	while (work) {
+		int ls, le;
+		work = 0;
+
+		ls = start;
+		le = start + 1;
+
+		/* while not over interval */
+		while (ls < end) {
+			int max_i = 0;
+			float v1[2];
+			/* divided to get more control */
+			float max_dist = epsilon / 10.0f;
+
+			/* find the next marked point */
+			while (marked[le] == 0) {
+				le++;
+			}
+
+			/* perpendicular vector to ls-le */
+			v1[1] = old_points2d[le].x - old_points2d[ls].x;
+			v1[0] = old_points2d[ls].y - old_points2d[le].y;
+
+			for (int i = ls + 1; i < le; i++) {
+				float mul;
+				float dist;
+				float v2[2];
+
+				v2[0] = old_points2d[i].x - old_points2d[ls].x;
+				v2[1] = old_points2d[i].y - old_points2d[ls].y;
+
+				if (v2[0] == 0 && v2[1] == 0) {
+					continue;
+				}
+
+				mul = (float)(v1[0] * v2[0] + v1[1] * v2[1]) / (float)(v2[0] * v2[0] + v2[1] * v2[1]);
+
+				dist = mul * mul * (v2[0] * v2[0] + v2[1] * v2[1]);
+
+				if (dist > max_dist) {
+					max_dist = dist;
+					max_i = i;
+				}
+			}
+
+			if (max_i != 0) {
+				work = 1;
+				marked[max_i] = 1;
+				totmarked++;
+			}
+
+			ls = le;
+			le = ls + 1;
+		}
+	}
+
+	/* adding points marked */
+	bGPDspoint *old_points = MEM_dupallocN(gps->points);
+	MDeformVert *old_dvert = MEM_dupallocN(gps->dvert);
+
+	/* resize gps */
+	gps->flag |= GP_STROKE_RECALC_CACHES;
+	gps->tot_triangles = 0;
+
+	int j = 0;
+	for (int i = 0; i < totpoints; i++) {
+		bGPDspoint *pt_src = &old_points[i];
+		bGPDspoint *pt = &gps->points[j];
+
+		MDeformVert *dvert_src = &old_dvert[i];
+		MDeformVert *dvert = &gps->dvert[j];
+
+		if ((marked[i]) || (i == 0) || (i == totpoints - 1)) {
+			memcpy(pt, pt_src, sizeof(bGPDspoint));
+			memcpy(dvert, dvert_src, sizeof(MDeformVert));
+			j++;
+		}
+		else {
+			BKE_gpencil_free_point_weights(dvert_src);
+		}
+	}
+
+	gps->totpoints = j;
+
+	MEM_SAFE_FREE(old_points);
+	MEM_SAFE_FREE(old_dvert);
+	MEM_SAFE_FREE(marked);
+}
+
+/* Simplify stroke using Ramer-Douglas-Peucker algorithm */
+void BKE_gpencil_simplify_stroke(bGPDstroke *gps, float factor)
+{
+	/* first create temp data and convert points to 2D */
+	vec2f *points2d = MEM_mallocN(sizeof(vec2f) * gps->totpoints, "GP Stroke temp 2d points");
+
+	gpencil_stroke_project_2d(gps->points, gps->totpoints, points2d);
+
+	gpencil_rdp_stroke(gps, points2d, factor);
+
+	MEM_SAFE_FREE(points2d);
+}
+
+/* Simplify alternate vertex of stroke except extrems */
+void BKE_gpencil_simplify_fixed(bGPDstroke *gps)
+{
+	if (gps->totpoints < 5) {
+		return;
+	}
+
+	/* save points */
+	bGPDspoint *old_points = MEM_dupallocN(gps->points);
+	MDeformVert *old_dvert = MEM_dupallocN(gps->dvert);
+
+	/* resize gps */
+	int newtot = (gps->totpoints - 2) / 2;
+	if (((gps->totpoints - 2) % 2) > 0) {
+		newtot++;
+	}
+	newtot += 2;
+
+	gps->points = MEM_recallocN(gps->points, sizeof(*gps->points) * newtot);
+	gps->dvert = MEM_recallocN(gps->dvert, sizeof(*gps->dvert) * newtot);
+	gps->flag |= GP_STROKE_RECALC_CACHES;
+	gps->tot_triangles = 0;
+
+	int j = 0;
+	for (int i = 0; i < gps->totpoints; i++) {
+		bGPDspoint *pt_src = &old_points[i];
+		bGPDspoint *pt = &gps->points[j];
+
+		MDeformVert *dvert_src = &old_dvert[i];
+		MDeformVert *dvert = &gps->dvert[j];
+
+		if ((i == 0) || (i == gps->totpoints - 1) || ((i % 2) > 0.0)) {
+			memcpy(pt, pt_src, sizeof(bGPDspoint));
+			memcpy(dvert, dvert_src, sizeof(MDeformVert));
+			j++;
+		}
+		else {
+			BKE_gpencil_free_point_weights(dvert_src);
+		}
+	}
+
+	gps->totpoints = j;
+
+	MEM_SAFE_FREE(old_points);
+	MEM_SAFE_FREE(old_dvert);
+}
+
+/* *************************************************** */
+/* Modifier Utilities */
+
+/* Lattice Modifier ---------------------------------- */
+/* Usually, evaluation of the lattice modifier is self-contained.
+ * However, since GP's modifiers operate on a per-stroke basis,
+ * we need to these two extra functions that called before/after
+ * each loop over all the geometry being evaluated.
+ */
+
+/* init lattice deform data */
+void BKE_gpencil_lattice_init(Object *ob)
+{
+	GpencilModifierData *md;
+	for (md = ob->greasepencil_modifiers.first; md; md = md->next) {
+		if (md->type == eGpencilModifierType_Lattice) {
+			LatticeGpencilModifierData *mmd = (LatticeGpencilModifierData *)md;
+			Object *latob = NULL;
+
+			latob = mmd->object;
+			if ((!latob) || (latob->type != OB_LATTICE)) {
+				return;
+			}
+			if (mmd->cache_data) {
+				end_latt_deform((struct LatticeDeformData *)mmd->cache_data);
+			}
+
+			/* init deform data */
+			mmd->cache_data = (struct LatticeDeformData *)init_latt_deform(latob, ob);
+		}
+	}
+}
+
+/* clear lattice deform data */
+void BKE_gpencil_lattice_clear(Object *ob)
+{
+	GpencilModifierData *md;
+	for (md = ob->greasepencil_modifiers.first; md; md = md->next) {
+		if (md->type == eGpencilModifierType_Lattice) {
+			LatticeGpencilModifierData *mmd = (LatticeGpencilModifierData *)md;
+			if ((mmd) && (mmd->cache_data)) {
+				end_latt_deform((struct LatticeDeformData *)mmd->cache_data);
+				mmd->cache_data = NULL;
+			}
+		}
+	}
+}
+
+/* *************************************************** */
+/* Modifier Methods - Evaluation Loops, etc. */
+
+/* check if exist geometry modifiers */
+bool BKE_gpencil_has_geometry_modifiers(Object *ob)
+{
+	GpencilModifierData *md;
+	for (md = ob->greasepencil_modifiers.first; md; md = md->next) {
+		const GpencilModifierTypeInfo *mti = BKE_gpencil_modifierType_getInfo(md->type);
+
+		if (mti && mti->generateStrokes) {
+			return true;
+		}
+	}
+	return false;
+}
+
+/* apply stroke modifiers */
+void BKE_gpencil_stroke_modifiers(Depsgraph *depsgraph, Object *ob, bGPDlayer *gpl, bGPDframe *UNUSED(gpf), bGPDstroke *gps, bool is_render)
+{
+	GpencilModifierData *md;
+	bGPdata *gpd = ob->data;
+	const bool is_edit = GPENCIL_ANY_EDIT_MODE(gpd);
+
+	for (md = ob->greasepencil_modifiers.first; md; md = md->next) {
+		if (GPENCIL_MODIFIER_ACTIVE(md, is_render))
+		{
+			const GpencilModifierTypeInfo *mti = BKE_gpencil_modifierType_getInfo(md->type);
+
+			if (GPENCIL_MODIFIER_EDIT(md, is_edit)) {
+				continue;
+			}
+
+			if (mti && mti->deformStroke) {
+				mti->deformStroke(md, depsgraph, ob, gpl, gps);
+			}
+		}
+	}
+}
+
+/* apply stroke geometry modifiers */
+void BKE_gpencil_geometry_modifiers(Depsgraph *depsgraph, Object *ob, bGPDlayer *gpl, bGPDframe *gpf, bool is_render)
+{
+	GpencilModifierData *md;
+	bGPdata *gpd = ob->data;
+	const bool is_edit = GPENCIL_ANY_EDIT_MODE(gpd);
+
+	for (md = ob->greasepencil_modifiers.first; md; md = md->next) {
+		if (GPENCIL_MODIFIER_ACTIVE(md, is_render))
+		{
+			const GpencilModifierTypeInfo *mti = BKE_gpencil_modifierType_getInfo(md->type);
+
+			if (GPENCIL_MODIFIER_EDIT(md, is_edit)) {
+				continue;
+			}
+
+			if (mti->generateStrokes) {
+				mti->generateStrokes(md, depsgraph, ob, gpl, gpf);
+			}
+		}
+	}
+}
+
+/* *************************************************** */
+
+void BKE_gpencil_eval_geometry(Depsgraph *depsgraph,
+                               bGPdata *gpd)
+{
+	DEG_debug_print_eval(depsgraph, __func__, gpd->id.name, gpd);
+	int ctime = (int)DEG_get_ctime(depsgraph);
+
+	/* update active frame */
+	for (bGPDlayer *gpl = gpd->layers.first; gpl; gpl = gpl->next) {
+		gpl->actframe = BKE_gpencil_layer_getframe(gpl, ctime, GP_GETFRAME_USE_PREV);
+	}
+
+	/* TODO: Move "derived_gpf" logic here from DRW_gpencil_populate_datablock()?
+	 * This would be better than inventing our own logic for this stuff...
+	 */
+
+	/* TODO: Move the following code to "BKE_gpencil_eval_done()" (marked as an exit node)
+	 * later when there's more happening here. For now, let's just keep this in here to avoid
+	 * needing to have one more node slowing down evaluation...
+	 */
+	if (DEG_is_active(depsgraph)) {
+		bGPdata *gpd_orig = (bGPdata *)DEG_get_original_id(&gpd->id);
+
+		/* sync "actframe" changes back to main-db too,
+		 * so that editing tools work with copy-on-write
+		 * when the current frame changes
+		 */
+		for (bGPDlayer *gpl = gpd_orig->layers.first; gpl; gpl = gpl->next) {
+			gpl->actframe = BKE_gpencil_layer_getframe(gpl, ctime, GP_GETFRAME_USE_PREV);
+		}
+	}
+}
+
+void BKE_gpencil_modifier_init(void)
+{
+	/* Initialize modifier types */
+	gpencil_modifier_type_init(modifier_gpencil_types); /* MOD_gpencil_util.c */
+}
+
+GpencilModifierData *BKE_gpencil_modifier_new(int type)
+{
+	const GpencilModifierTypeInfo *mti = BKE_gpencil_modifierType_getInfo(type);
+	GpencilModifierData *md = MEM_callocN(mti->struct_size, mti->struct_name);
+
+	/* note, this name must be made unique later */
+	BLI_strncpy(md->name, DATA_(mti->name), sizeof(md->name));
+
+	md->type = type;
+	md->mode = eGpencilModifierMode_Realtime | eGpencilModifierMode_Render | eGpencilModifierMode_Expanded;
+	md->flag = eGpencilModifierFlag_StaticOverride_Local;
+
+	if (mti->flags & eGpencilModifierTypeFlag_EnableInEditmode)
+		md->mode |= eGpencilModifierMode_Editmode;
+
+	if (mti->initData) mti->initData(md);
+
+	return md;
+}
+
+static void modifier_free_data_id_us_cb(void *UNUSED(userData), Object *UNUSED(ob), ID **idpoin, int cb_flag)
+{
+	ID *id = *idpoin;
+	if (id != NULL && (cb_flag & IDWALK_CB_USER) != 0) {
+		id_us_min(id);
+	}
+}
+
+void BKE_gpencil_modifier_free_ex(GpencilModifierData *md, const int flag)
+{
+	const GpencilModifierTypeInfo *mti = BKE_gpencil_modifierType_getInfo(md->type);
+
+	if ((flag & LIB_ID_CREATE_NO_USER_REFCOUNT) == 0) {
+		if (mti->foreachIDLink) {
+			mti->foreachIDLink(md, NULL, modifier_free_data_id_us_cb, NULL);
+		}
+		else if (mti->foreachObjectLink) {
+			mti->foreachObjectLink(md, NULL, (GreasePencilObjectWalkFunc)modifier_free_data_id_us_cb, NULL);
+		}
+	}
+
+	if (mti->freeData) mti->freeData(md);
+	if (md->error) MEM_freeN(md->error);
+
+	MEM_freeN(md);
+}
+
+void BKE_gpencil_modifier_free(GpencilModifierData *md)
+{
+	BKE_gpencil_modifier_free_ex(md, 0);
+}
+
+/* check unique name */
+bool BKE_gpencil_modifier_unique_name(ListBase *modifiers, GpencilModifierData *gmd)
+{
+	if (modifiers && gmd) {
+		const GpencilModifierTypeInfo *gmti = BKE_gpencil_modifierType_getInfo(gmd->type);
+		return BLI_uniquename(modifiers, gmd, DATA_(gmti->name), '.', offsetof(GpencilModifierData, name), sizeof(gmd->name));
+	}
+	return false;
+}
+
+bool BKE_gpencil_modifier_dependsOnTime(GpencilModifierData *md)
+{
+	const GpencilModifierTypeInfo *mti = BKE_gpencil_modifierType_getInfo(md->type);
+
+	return mti->dependsOnTime && mti->dependsOnTime(md);
+}
+
+const GpencilModifierTypeInfo *BKE_gpencil_modifierType_getInfo(GpencilModifierType type)
+{
+	/* type unsigned, no need to check < 0 */
+	if (type < NUM_GREASEPENCIL_MODIFIER_TYPES && modifier_gpencil_types[type]->name[0] != '\0') {
+		return modifier_gpencil_types[type];
+	}
+	else {
+		return NULL;
+	}
+}
+
+void BKE_gpencil_modifier_copyData_generic(const GpencilModifierData *md_src, GpencilModifierData *md_dst)
+{
+	const GpencilModifierTypeInfo *mti = BKE_gpencil_modifierType_getInfo(md_src->type);
+
+	/* md_dst may have alredy be fully initialized with some extra allocated data,
+	* we need to free it now to avoid memleak. */
+	if (mti->freeData) {
+		mti->freeData(md_dst);
+	}
+
+	const size_t data_size = sizeof(GpencilModifierData);
+	const char *md_src_data = ((const char *)md_src) + data_size;
+	char       *md_dst_data = ((char *)md_dst) + data_size;
+	BLI_assert(data_size <= (size_t)mti->struct_size);
+	memcpy(md_dst_data, md_src_data, (size_t)mti->struct_size - data_size);
+}
+
+static void gpencil_modifier_copy_data_id_us_cb(void *UNUSED(userData), Object *UNUSED(ob), ID **idpoin, int cb_flag)
+{
+	ID *id = *idpoin;
+	if (id != NULL && (cb_flag & IDWALK_CB_USER) != 0) {
+		id_us_plus(id);
+	}
+}
+
+void BKE_gpencil_modifier_copyData_ex(GpencilModifierData *md, GpencilModifierData *target, const int flag)
+{
+	const GpencilModifierTypeInfo *mti = BKE_gpencil_modifierType_getInfo(md->type);
+
+	target->mode = md->mode;
+	target->flag = md->flag;
+
+	if (mti->copyData) {
+		mti->copyData(md, target);
+	}
+
+	if ((flag & LIB_ID_CREATE_NO_USER_REFCOUNT) == 0) {
+		if (mti->foreachIDLink) {
+			mti->foreachIDLink(target, NULL, gpencil_modifier_copy_data_id_us_cb, NULL);
+		}
+		else if (mti->foreachObjectLink) {
+			mti->foreachObjectLink(target, NULL, (GreasePencilObjectWalkFunc)gpencil_modifier_copy_data_id_us_cb, NULL);
+		}
+	}
+}
+
+void BKE_gpencil_modifier_copyData(GpencilModifierData *md, GpencilModifierData *target)
+{
+	BKE_gpencil_modifier_copyData_ex(md, target, 0);
+}
+
+GpencilModifierData *BKE_gpencil_modifiers_findByType(Object *ob, GpencilModifierType type)
+{
+	GpencilModifierData *md = ob->greasepencil_modifiers.first;
+
+	for (; md; md = md->next)
+		if (md->type == type)
+			break;
+
+	return md;
+}
+
+void BKE_gpencil_modifiers_foreachIDLink(Object *ob, GreasePencilIDWalkFunc walk, void *userData)
+{
+	GpencilModifierData *md = ob->greasepencil_modifiers.first;
+
+	for (; md; md = md->next) {
+		const GpencilModifierTypeInfo *mti = BKE_gpencil_modifierType_getInfo(md->type);
+
+		if (mti->foreachIDLink) mti->foreachIDLink(md, ob, walk, userData);
+		else if (mti->foreachObjectLink) {
+			/* each Object can masquerade as an ID, so this should be OK */
+			GreasePencilObjectWalkFunc fp = (GreasePencilObjectWalkFunc)walk;
+			mti->foreachObjectLink(md, ob, fp, userData);
+		}
+	}
+}
+
+void BKE_gpencil_modifiers_foreachTexLink(Object *ob, GreasePencilTexWalkFunc walk, void *userData)
+{
+	GpencilModifierData *md = ob->greasepencil_modifiers.first;
+
+	for (; md; md = md->next) {
+		const GpencilModifierTypeInfo *mti = BKE_gpencil_modifierType_getInfo(md->type);
+
+		if (mti->foreachTexLink)
+			mti->foreachTexLink(md, ob, walk, userData);
+	}
+}
+
+GpencilModifierData *BKE_gpencil_modifiers_findByName(Object *ob, const char *name)
+{
+	return BLI_findstring(&(ob->greasepencil_modifiers), name, offsetof(GpencilModifierData, name));
+}
+
+/* helper function for per-instance positioning */
+void BKE_gpencil_instance_modifier_instance_tfm(InstanceGpencilModifierData *mmd, const int elem_idx[3], float r_mat[4][4])
+{
+	float offset[3], rot[3], scale[3];
+	int ri = mmd->rnd[0];
+	float factor;
+
+	offset[0] = mmd->offset[0] * elem_idx[0];
+	offset[1] = mmd->offset[1] * elem_idx[1];
+	offset[2] = mmd->offset[2] * elem_idx[2];
+
+	/* rotation */
+	if (mmd->flag & GP_INSTANCE_RANDOM_ROT) {
+		factor = mmd->rnd_rot * mmd->rnd[ri];
+		mul_v3_v3fl(rot, mmd->rot, factor);
+		add_v3_v3(rot, mmd->rot);
+	}
+	else {
+		copy_v3_v3(rot, mmd->rot);
+	}
+
+	/* scale */
+	if (mmd->flag & GP_INSTANCE_RANDOM_SIZE) {
+		factor = mmd->rnd_size * mmd->rnd[ri];
+		mul_v3_v3fl(scale, mmd->scale, factor);
+		add_v3_v3(scale, mmd->scale);
+	}
+	else {
+		copy_v3_v3(scale, mmd->scale);
+	}
+
+	/* advance random index */
+	mmd->rnd[0]++;
+	if (mmd->rnd[0] > 19) {
+		mmd->rnd[0] = 1;
+	}
+
+	/* calculate matrix */
+	loc_eul_size_to_mat4(r_mat, offset, rot, scale);
+}
diff --git a/source/blender/blenkernel/intern/icons.c b/source/blender/blenkernel/intern/icons.c
index 1c2575dfa52..3a4bf53e22d 100644
--- a/source/blender/blenkernel/intern/icons.c
+++ b/source/blender/blenkernel/intern/icons.c
@@ -37,6 +37,8 @@
 
 #include "MEM_guardedalloc.h"
 
+#include "DNA_brush_types.h"
+#include "DNA_gpencil_types.h"
 #include "DNA_group_types.h"
 #include "DNA_lamp_types.h"
 #include "DNA_material_types.h"
@@ -45,7 +47,6 @@
 #include "DNA_screen_types.h"
 #include "DNA_texture_types.h"
 #include "DNA_world_types.h"
-#include "DNA_brush_types.h"
 
 #include "BLI_utildefines.h"
 #include "BLI_ghash.h"
@@ -127,6 +128,9 @@ static void icon_free_data(int icon_id, Icon *icon)
 	else if (icon->obj_type == ICON_DATA_PREVIEW) {
 		((PreviewImage *)(icon->obj))->icon_id = 0;
 	}
+	else if (icon->obj_type == ICON_DATA_GPLAYER) {
+		((bGPDlayer *)(icon->obj))->runtime.icon_id = 0;
+	}
 	else if (icon->obj_type == ICON_DATA_GEOM) {
 		((struct Icon_Geom *)(icon->obj))->icon_id = 0;
 	}
@@ -598,6 +602,44 @@ int BKE_icon_id_ensure(struct ID *id)
 	return icon_id_ensure_create_icon(id);
 }
 
+
+static int icon_gplayer_color_ensure_create_icon(bGPDlayer *gpl)
+{
+	BLI_assert(BLI_thread_is_main());
+
+	/* NOTE: The color previews for GP Layers don't really need
+	 * to be "rendered" to image per se (as it will just be a plain
+	 * colored rectangle), we need to define icon data here so that
+	 * we can store a pointer to the layer data in icon->obj.
+	 */
+	Icon *icon = icon_create(gpl->runtime.icon_id, ICON_DATA_GPLAYER, gpl);
+	icon->flag = ICON_FLAG_MANAGED;
+
+	return gpl->runtime.icon_id;
+}
+
+int BKE_icon_gplayer_color_ensure(bGPDlayer *gpl)
+{
+	/* Never handle icons in non-main thread! */
+	BLI_assert(BLI_thread_is_main());
+
+	if (!gpl || G.background) {
+		return 0;
+	}
+
+	if (gpl->runtime.icon_id)
+		return gpl->runtime.icon_id;
+
+	gpl->runtime.icon_id = get_next_free_id();
+
+	if (!gpl->runtime.icon_id) {
+		printf("%s: Internal error - not enough IDs\n", __func__);
+		return 0;
+	}
+
+	return icon_gplayer_color_ensure_create_icon(gpl);
+}
+
 /**
  * Return icon id of given preview, or create new icon if not found.
  */
diff --git a/source/blender/blenkernel/intern/library.c b/source/blender/blenkernel/intern/library.c
index 351214ed72b..1d70d9db1e9 100644
--- a/source/blender/blenkernel/intern/library.c
+++ b/source/blender/blenkernel/intern/library.c
@@ -1073,6 +1073,7 @@ int set_listbasepointers(Main *main, ListBase **lb)
 	lb[INDEX_ID_IP] = &(main->ipo);
 	lb[INDEX_ID_AC] = &(main->action); /* moved here to avoid problems when freeing with animato (aligorith) */
 	lb[INDEX_ID_KE] = &(main->key);
+	lb[INDEX_ID_PAL] = &(main->palettes); /* referenced by gpencil, so needs to be before that to avoid crashes */
 	lb[INDEX_ID_GD] = &(main->gpencil); /* referenced by nodes, objects, view, scene etc, before to free after. */
 	lb[INDEX_ID_NT] = &(main->nodetree);
 	lb[INDEX_ID_IM] = &(main->image);
diff --git a/source/blender/blenkernel/intern/library_query.c b/source/blender/blenkernel/intern/library_query.c
index 93fdd3349bf..473dd787a69 100644
--- a/source/blender/blenkernel/intern/library_query.c
+++ b/source/blender/blenkernel/intern/library_query.c
@@ -417,7 +417,6 @@ void BKE_library_foreach_ID_link(Main *bmain, ID *id, LibraryIDLinkCallback call
 					SEQ_END
 				}
 
-				CALLBACK_INVOKE(scene->gpd, IDWALK_CB_USER);
 
 				for (CollectionObject *cob = scene->master_collection->gobject.first; cob; cob = cob->next) {
 					CALLBACK_INVOKE(cob->ob, IDWALK_CB_USER);
@@ -478,6 +477,9 @@ void BKE_library_foreach_ID_link(Main *bmain, ID *id, LibraryIDLinkCallback call
 					if (toolsett->uvsculpt) {
 						library_foreach_paint(&data, &toolsett->uvsculpt->paint);
 					}
+					if (toolsett->gp_paint) {
+						library_foreach_paint(&data, &toolsett->gp_paint->paint);
+					}
 				}
 
 				if (scene->rigidbody_world) {
@@ -641,6 +643,10 @@ void BKE_library_foreach_ID_link(Main *bmain, ID *id, LibraryIDLinkCallback call
 				if (material->texpaintslot != NULL) {
 					CALLBACK_INVOKE(material->texpaintslot->ima, IDWALK_CB_NOP);
 				}
+				if (material->gp_style != NULL) {
+					CALLBACK_INVOKE(material->gp_style->sima, IDWALK_CB_USER);
+					CALLBACK_INVOKE(material->gp_style->ima, IDWALK_CB_USER);
+				}
 				break;
 			}
 
@@ -758,6 +764,9 @@ void BKE_library_foreach_ID_link(Main *bmain, ID *id, LibraryIDLinkCallback call
 				CALLBACK_INVOKE(brush->toggle_brush, IDWALK_CB_NOP);
 				CALLBACK_INVOKE(brush->clone.image, IDWALK_CB_NOP);
 				CALLBACK_INVOKE(brush->paint_curve, IDWALK_CB_USER);
+				if (brush->gpencil_settings) {
+					CALLBACK_INVOKE(brush->gpencil_settings->material, IDWALK_CB_USER);
+				}
 				library_foreach_mtex(&data, &brush->mtex);
 				library_foreach_mtex(&data, &brush->mask_mtex);
 				break;
@@ -941,10 +950,15 @@ void BKE_library_foreach_ID_link(Main *bmain, ID *id, LibraryIDLinkCallback call
 			case ID_GD:
 			{
 				bGPdata *gpencil = (bGPdata *) id;
+				/* materials */
+				for (i = 0; i < gpencil->totcol; i++) {
+					CALLBACK_INVOKE(gpencil->mat[i], IDWALK_CB_USER);
+				}
 
-				for (bGPDlayer *gp_layer = gpencil->layers.first; gp_layer; gp_layer = gp_layer->next) {
-					CALLBACK_INVOKE(gp_layer->parent, IDWALK_CB_NOP);
+				for (bGPDlayer *gplayer = gpencil->layers.first; gplayer != NULL; gplayer = gplayer->next) {
+					CALLBACK_INVOKE(gplayer->parent, IDWALK_CB_NOP);
 				}
+
 				break;
 			}
 
@@ -1072,7 +1086,7 @@ bool BKE_library_id_can_use_idtype(ID *id_owner, const short id_type_used)
 			return true;
 #endif
 		case ID_BR:
-			return ELEM(id_type_used, ID_BR, ID_IM, ID_PC, ID_TE);
+			return ELEM(id_type_used, ID_BR, ID_IM, ID_PC, ID_TE, ID_MA);
 		case ID_PA:
 			return ELEM(id_type_used, ID_OB, ID_GR, ID_TE);
 		case ID_MC:
@@ -1083,6 +1097,8 @@ bool BKE_library_id_can_use_idtype(ID *id_owner, const short id_type_used)
 			return (ELEM(id_type_used, ID_TE, ID_OB));
 		case ID_LP:
 			return ELEM(id_type_used, ID_IM);
+		case ID_GD:
+			return ELEM(id_type_used, ID_MA);
 		case ID_WS:
 			return ELEM(id_type_used, ID_SCR, ID_SCE);
 		case ID_IM:
@@ -1091,7 +1107,6 @@ bool BKE_library_id_can_use_idtype(ID *id_owner, const short id_type_used)
 		case ID_SO:
 		case ID_AR:
 		case ID_AC:
-		case ID_GD:
 		case ID_WM:
 		case ID_PAL:
 		case ID_PC:
diff --git a/source/blender/blenkernel/intern/material.c b/source/blender/blenkernel/intern/material.c
index 28d75811185..03ec26c07d0 100644
--- a/source/blender/blenkernel/intern/material.c
+++ b/source/blender/blenkernel/intern/material.c
@@ -43,6 +43,7 @@
 #include "DNA_mesh_types.h"
 #include "DNA_meshdata_types.h"
 #include "DNA_customdata_types.h"
+#include "DNA_gpencil_types.h"
 #include "DNA_ID.h"
 #include "DNA_meta_types.h"
 #include "DNA_node_types.h"
@@ -58,6 +59,7 @@
 #include "BKE_animsys.h"
 #include "BKE_displist.h"
 #include "BKE_global.h"
+#include "BKE_gpencil.h"
 #include "BKE_icons.h"
 #include "BKE_image.h"
 #include "BKE_library.h"
@@ -103,10 +105,30 @@ void BKE_material_free(Material *ma)
 
 	MEM_SAFE_FREE(ma->texpaintslot);
 
+	MEM_SAFE_FREE(ma->gp_style);
+
 	BKE_icon_id_delete((ID *)ma);
 	BKE_previewimg_free(&ma->preview);
 }
 
+void BKE_material_init_gpencil_settings(Material *ma)
+{
+	if ((ma) && (ma->gp_style == NULL)) {
+		ma->gp_style = MEM_callocN(sizeof(MaterialGPencilStyle), "Grease Pencil Material Settings");
+
+		MaterialGPencilStyle *gp_style = ma->gp_style;
+		/* set basic settings */
+		gp_style->stroke_rgba[3] = 1.0f;
+		gp_style->pattern_gridsize = 0.1f;
+		gp_style->gradient_radius = 0.5f;
+		ARRAY_SET_ITEMS(gp_style->mix_rgba, 1.0f, 1.0f, 1.0f, 0.2f);
+		ARRAY_SET_ITEMS(gp_style->gradient_scale, 1.0f, 1.0f);
+		ARRAY_SET_ITEMS(gp_style->texture_scale, 1.0f, 1.0f);
+		gp_style->texture_opacity = 1.0f;
+		gp_style->texture_pixsize = 100.0f;
+	}
+}
+
 void BKE_material_init(Material *ma)
 {
 	BLI_assert(MEMCMP_STRUCT_OFS_IS_ZERO(ma, id));
@@ -124,6 +146,7 @@ void BKE_material_init(Material *ma)
 	ma->preview = NULL;
 
 	ma->alpha_threshold = 0.5f;
+
 }
 
 Material *BKE_material_add(Main *bmain, const char *name)
@@ -137,6 +160,19 @@ Material *BKE_material_add(Main *bmain, const char *name)
 	return ma;
 }
 
+Material *BKE_material_add_gpencil(Main *bmain, const char *name)
+{
+	Material *ma;
+
+	ma = BKE_material_add(bmain, name);
+
+	/* grease pencil settings */
+	BKE_material_init_gpencil_settings(ma);
+
+	return ma;
+}
+
+
 /**
  * Only copy internal data of Material ID from source to already allocated/initialized destination.
  * You probably nerver want to use that directly, use id_copy or BKE_id_copy_ex for typical needs.
@@ -164,6 +200,10 @@ void BKE_material_copy_data(Main *bmain, Material *ma_dst, const Material *ma_sr
 		ma_dst->texpaintslot = MEM_dupallocN(ma_src->texpaintslot);
 	}
 
+	if (ma_src->gp_style != NULL) {
+		ma_dst->gp_style = MEM_dupallocN(ma_src->gp_style);
+	}
+
 	BLI_listbase_clear(&ma_dst->gpumaterial);
 
 	/* TODO Duplicate Engine Settings and set runtime to NULL */
@@ -199,6 +239,7 @@ Material *BKE_material_localize(Material *ma)
 	man->texpaintslot = NULL;
 	man->preview = NULL;
 
+	/* man->gp_style = NULL; */ /* XXX: We probably don't want to clear here, or else we may get problems with COW later? */
 	BLI_listbase_clear(&man->gpumaterial);
 
 	/* TODO Duplicate Engine Settings and set runtime to NULL */
@@ -218,6 +259,7 @@ Material ***give_matarar(Object *ob)
 	Mesh *me;
 	Curve *cu;
 	MetaBall *mb;
+	bGPdata *gpd;
 
 	if (ob->type == OB_MESH) {
 		me = ob->data;
@@ -231,6 +273,10 @@ Material ***give_matarar(Object *ob)
 		mb = ob->data;
 		return &(mb->mat);
 	}
+	else if (ob->type == OB_GPENCIL) {
+		gpd = ob->data;
+		return &(gpd->mat);
+	}
 	return NULL;
 }
 
@@ -239,6 +285,7 @@ short *give_totcolp(Object *ob)
 	Mesh *me;
 	Curve *cu;
 	MetaBall *mb;
+	bGPdata *gpd;
 
 	if (ob->type == OB_MESH) {
 		me = ob->data;
@@ -252,6 +299,10 @@ short *give_totcolp(Object *ob)
 		mb = ob->data;
 		return &(mb->totcol);
 	}
+	else if (ob->type == OB_GPENCIL) {
+		gpd = ob->data;
+		return &(gpd->totcol);
+	}
 	return NULL;
 }
 
@@ -286,6 +337,8 @@ short *give_totcolp_id(ID *id)
 			return &(((Curve *)id)->totcol);
 		case ID_MB:
 			return &(((MetaBall *)id)->totcol);
+		case ID_GD:
+			return &(((bGPdata *)id)->totcol);
 		default:
 			break;
 	}
@@ -307,6 +360,9 @@ static void material_data_index_remove_id(ID *id, short index)
 		case ID_MB:
 			/* meta-elems don't have materials atm */
 			break;
+		case ID_GD:
+			BKE_gpencil_material_index_remove((bGPdata *)id, index);
+			break;
 		default:
 			break;
 	}
@@ -487,6 +543,21 @@ Material *give_current_material(Object *ob, short act)
 	return ma;
 }
 
+MaterialGPencilStyle *BKE_material_gpencil_settings_get(Object *ob, short act)
+{
+	Material *ma = give_current_material(ob, act);
+	if (ma != NULL) {
+		if (ma->gp_style == NULL) {
+			BKE_material_init_gpencil_settings(ma);
+		}
+
+		return ma->gp_style;
+	}
+	else {
+		return NULL;
+	}
+}
+
 Material *give_node_material(Material *ma)
 {
 	if (ma && ma->use_nodes && ma->nodetree) {
@@ -727,6 +798,9 @@ void BKE_material_remap_object(Object *ob, const unsigned int *remap)
 	else if (ELEM(ob->type, OB_CURVE, OB_SURF, OB_FONT)) {
 		BKE_curve_material_remap(ob->data, remap, ob->totcol);
 	}
+	if (ob->type == OB_GPENCIL) {
+		BKE_gpencil_material_remap(ob->data, remap, ob->totcol);
+	}
 	else {
 		/* add support for this object data! */
 		BLI_assert(matar == NULL);
@@ -924,7 +998,7 @@ bool BKE_object_material_slot_remove(Main *bmain, Object *ob)
 	}
 
 	/* check indices from mesh */
-	if (ELEM(ob->type, OB_MESH, OB_CURVE, OB_SURF, OB_FONT)) {
+	if (ELEM(ob->type, OB_MESH, OB_CURVE, OB_SURF, OB_FONT, OB_GPENCIL)) {
 		material_data_index_remove_id((ID *)ob->data, actcol - 1);
 		if (ob->runtime.curve_cache) {
 			BKE_displist_free(&ob->runtime.curve_cache->disp);
diff --git a/source/blender/blenkernel/intern/object.c b/source/blender/blenkernel/intern/object.c
index 21b5bb89f19..c88de006eba 100644
--- a/source/blender/blenkernel/intern/object.c
+++ b/source/blender/blenkernel/intern/object.c
@@ -41,6 +41,7 @@
 #include "DNA_camera_types.h"
 #include "DNA_constraint_types.h"
 #include "DNA_gpencil_types.h"
+#include "DNA_gpencil_modifier_types.h"
 #include "DNA_group_types.h"
 #include "DNA_key_types.h"
 #include "DNA_lamp_types.h"
@@ -53,6 +54,7 @@
 #include "DNA_scene_types.h"
 #include "DNA_screen_types.h"
 #include "DNA_sequence_types.h"
+#include "DNA_shader_fx_types.h"
 #include "DNA_smoke_types.h"
 #include "DNA_space_types.h"
 #include "DNA_view3d_types.h"
@@ -86,6 +88,7 @@
 #include "BKE_displist.h"
 #include "BKE_effect.h"
 #include "BKE_fcurve.h"
+#include "BKE_gpencil_modifier.h"
 #include "BKE_icons.h"
 #include "BKE_key.h"
 #include "BKE_lamp.h"
@@ -110,12 +113,14 @@
 #include "BKE_rigidbody.h"
 #include "BKE_scene.h"
 #include "BKE_sequencer.h"
+#include "BKE_shader_fx.h"
 #include "BKE_speaker.h"
 #include "BKE_softbody.h"
 #include "BKE_subsurf.h"
 #include "BKE_material.h"
 #include "BKE_camera.h"
 #include "BKE_image.h"
+#include "BKE_gpencil.h"
 
 #include "DEG_depsgraph.h"
 #include "DEG_depsgraph_query.h"
@@ -185,11 +190,15 @@ void BKE_object_free_curve_cache(Object *ob)
 void BKE_object_free_modifiers(Object *ob, const int flag)
 {
 	ModifierData *md;
+	GpencilModifierData *gp_md;
 
 	while ((md = BLI_pophead(&ob->modifiers))) {
 		modifier_free_ex(md, flag);
 	}
 
+	while ((gp_md = BLI_pophead(&ob->greasepencil_modifiers))) {
+		BKE_gpencil_modifier_free_ex(gp_md, flag);
+	}
 	/* particle modifiers were freed, so free the particlesystems as well */
 	BKE_object_free_particlesystems(ob);
 
@@ -200,6 +209,15 @@ void BKE_object_free_modifiers(Object *ob, const int flag)
 	BKE_object_free_derived_caches(ob);
 }
 
+void BKE_object_free_shaderfx(Object *ob, const int flag)
+{
+	ShaderFxData *fx;
+
+	while ((fx = BLI_pophead(&ob->shader_fx))) {
+		BKE_shaderfx_free_ex(fx, flag);
+	}
+}
+
 void BKE_object_modifier_hook_reset(Object *ob, HookModifierData *hmd)
 {
 	/* reset functionality */
@@ -222,6 +240,29 @@ void BKE_object_modifier_hook_reset(Object *ob, HookModifierData *hmd)
 	}
 }
 
+void BKE_object_modifier_gpencil_hook_reset(Object *ob, HookGpencilModifierData *hmd)
+{
+	if (hmd->object == NULL) {
+		return;
+	}
+	/* reset functionality */
+	bPoseChannel *pchan = BKE_pose_channel_find_name(hmd->object->pose, hmd->subtarget);
+
+	if (hmd->subtarget[0] && pchan) {
+		float imat[4][4], mat[4][4];
+
+		/* calculate the world-space matrix for the pose-channel target first, then carry on as usual */
+		mul_m4_m4m4(mat, hmd->object->obmat, pchan->pose_mat);
+
+		invert_m4_m4(imat, mat);
+		mul_m4_m4m4(hmd->parentinv, imat, ob->obmat);
+	}
+	else {
+		invert_m4_m4(hmd->object->imat, hmd->object->obmat);
+		mul_m4_m4m4(hmd->parentinv, hmd->object->imat, ob->obmat);
+	}
+}
+
 bool BKE_object_support_modifier_type_check(const Object *ob, int modifier_type)
 {
 	const ModifierTypeInfo *mti;
@@ -428,6 +469,7 @@ void BKE_object_free(Object *ob)
 
 	/* BKE_<id>_free shall never touch to ID->us. Never ever. */
 	BKE_object_free_modifiers(ob, LIB_ID_CREATE_NO_USER_REFCOUNT);
+	BKE_object_free_shaderfx(ob, LIB_ID_CREATE_NO_USER_REFCOUNT);
 
 	MEM_SAFE_FREE(ob->mat);
 	MEM_SAFE_FREE(ob->matbits);
@@ -653,6 +695,7 @@ static const char *get_obdata_defname(int type)
 		case OB_ARMATURE: return DATA_("Armature");
 		case OB_SPEAKER: return DATA_("Speaker");
 		case OB_EMPTY: return DATA_("Empty");
+		case OB_GPENCIL: return DATA_("GPencil");
 		default:
 			printf("get_obdata_defname: Internal error, bad type: %d\n", type);
 			return DATA_("Empty");
@@ -677,6 +720,7 @@ void *BKE_object_obdata_add_from_type(Main *bmain, int type, const char *name)
 		case OB_ARMATURE:  return BKE_armature_add(bmain, name);
 		case OB_SPEAKER:   return BKE_speaker_add(bmain, name);
 		case OB_LIGHTPROBE:return BKE_lightprobe_add(bmain, name);
+		case OB_GPENCIL:   return BKE_gpencil_data_addnew(bmain, name);
 		case OB_EMPTY:     return NULL;
 		default:
 			printf("%s: Internal error, bad type: %d\n", __func__, type);
@@ -810,7 +854,7 @@ Object *BKE_object_add(
 /**
  * Add a new object, using another one as a reference
  *
- * /param ob_src object to use to determine the collections of the new object.
+ * \param ob_src object to use to determine the collections of the new object.
  */
 Object *BKE_object_add_from(
         Main *bmain, Scene *scene, ViewLayer *view_layer,
@@ -828,6 +872,41 @@ Object *BKE_object_add_from(
 	return ob;
 }
 
+/**
+ * Add a new object, but assign the given datablock as the ob->data
+ * for the newly created object.
+ *
+ * \param data The datablock to assign as ob->data for the new object.
+ *             This is assumed to be of the correct type.
+ * \param do_id_user If true, id_us_plus() will be called on data when
+ *                 assigning it to the object.
+ */
+Object *BKE_object_add_for_data(
+        Main *bmain, ViewLayer *view_layer,
+        int type, const char *name, ID *data, bool do_id_user)
+{
+	Object *ob;
+	Base *base;
+	LayerCollection *layer_collection;
+
+	/* same as object_add_common, except we don't create new ob->data */
+	ob = BKE_object_add_only_object(bmain, type, name);
+	ob->data = data;
+	if (do_id_user) id_us_plus(data);
+
+	BKE_view_layer_base_deselect_all(view_layer);
+	DEG_id_tag_update_ex(bmain, &ob->id, OB_RECALC_OB | OB_RECALC_DATA | OB_RECALC_TIME);
+
+	layer_collection = BKE_layer_collection_get_active(view_layer);
+	BKE_collection_object_add(bmain, layer_collection->collection, ob);
+
+	base = BKE_view_layer_base_find(view_layer, ob);
+	BKE_view_layer_base_select(view_layer, base);
+
+	return ob;
+}
+
+
 void BKE_object_copy_softbody(struct Object *ob_dst, const struct Object *ob_src, const int flag)
 {
 	SoftBody *sb = ob_src->soft;
@@ -1153,6 +1232,8 @@ void BKE_object_transform_copy(Object *ob_tar, const Object *ob_src)
 void BKE_object_copy_data(Main *bmain, Object *ob_dst, const Object *ob_src, const int flag)
 {
 	ModifierData *md;
+	GpencilModifierData *gmd;
+	ShaderFxData *fx;
 
 	/* Do not copy runtime data. */
 	BKE_object_runtime_reset(ob_dst);
@@ -1179,6 +1260,24 @@ void BKE_object_copy_data(Main *bmain, Object *ob_dst, const Object *ob_src, con
 		BLI_addtail(&ob_dst->modifiers, nmd);
 	}
 
+	BLI_listbase_clear(&ob_dst->greasepencil_modifiers);
+
+	for (gmd = ob_src->greasepencil_modifiers.first; gmd; gmd = gmd->next) {
+		GpencilModifierData *nmd = BKE_gpencil_modifier_new(gmd->type);
+		BLI_strncpy(nmd->name, gmd->name, sizeof(nmd->name));
+		BKE_gpencil_modifier_copyData_ex(gmd, nmd, flag_subdata);
+		BLI_addtail(&ob_dst->greasepencil_modifiers, nmd);
+	}
+
+	BLI_listbase_clear(&ob_dst->shader_fx);
+
+	for (fx = ob_src->shader_fx.first; fx; fx = fx->next) {
+		ShaderFxData *nfx = BKE_shaderfx_new(fx->type);
+		BLI_strncpy(nfx->name, fx->name, sizeof(nfx->name));
+		BKE_shaderfx_copyData_ex(fx, nfx, flag_subdata);
+		BLI_addtail(&ob_dst->shader_fx, nfx);
+	}
+
 	if (ob_src->pose) {
 		copy_object_pose(ob_dst, ob_src, flag_subdata);
 		/* backwards compat... non-armatures can get poses in older files? */
@@ -1210,6 +1309,10 @@ void BKE_object_copy_data(Main *bmain, Object *ob_dst, const Object *ob_src, con
 	BLI_listbase_clear((ListBase *)&ob_dst->drawdata);
 	BLI_listbase_clear(&ob_dst->pc_ids);
 
+	/* grease pencil: clean derived data */
+	if (ob_dst->type == OB_GPENCIL)
+		BKE_gpencil_free_derived_frames(ob_dst->data);
+
 	ob_dst->avs = ob_src->avs;
 	ob_dst->mpath = animviz_copy_motionpath(ob_src->mpath);
 
@@ -1469,6 +1572,11 @@ void BKE_object_obdata_size_init(struct Object *ob, const float size)
 			ob->empty_drawsize *= size;
 			break;
 		}
+		case OB_GPENCIL:
+		{
+			ob->empty_drawsize *= size;
+			break;
+		}
 		case OB_FONT:
 		{
 			Curve *cu = ob->data;
@@ -2452,7 +2560,7 @@ void BKE_object_minmax(Object *ob, float min_r[3], float max_r[3], const bool us
 		float size[3];
 
 		copy_v3_v3(size, ob->size);
-		if (ob->type == OB_EMPTY) {
+		if ((ob->type == OB_EMPTY) || (ob->type == OB_GPENCIL)) {
 			mul_v3_fl(size, ob->empty_drawsize);
 		}
 
@@ -3694,6 +3802,88 @@ bool BKE_object_modifier_use_time(Object *ob, ModifierData *md)
 	return false;
 }
 
+bool BKE_object_modifier_gpencil_use_time(Object *ob, GpencilModifierData *md)
+{
+	if (BKE_gpencil_modifier_dependsOnTime(md)) {
+		return true;
+	}
+
+	/* Check whether modifier is animated. */
+	/* TODO (Aligorith): this should be handled as part of build_animdata() */
+	if (ob->adt) {
+		AnimData *adt = ob->adt;
+		FCurve *fcu;
+
+		char pattern[MAX_NAME + 32];
+		BLI_snprintf(pattern, sizeof(pattern), "grease_pencil_modifiers[\"%s\"]", md->name);
+
+		/* action - check for F-Curves with paths containing 'grease_pencil_modifiers[' */
+		if (adt->action) {
+			for (fcu = (FCurve *)adt->action->curves.first;
+				fcu != NULL;
+				fcu = (FCurve *)fcu->next)
+			{
+				if (fcu->rna_path && strstr(fcu->rna_path, pattern))
+					return true;
+			}
+		}
+
+		/* This here allows modifier properties to get driven and still update properly
+		*
+		*/
+		for (fcu = (FCurve *)adt->drivers.first;
+			fcu != NULL;
+			fcu = (FCurve *)fcu->next)
+		{
+			if (fcu->rna_path && strstr(fcu->rna_path, pattern))
+				return true;
+		}
+	}
+
+	return false;
+}
+
+bool BKE_object_shaderfx_use_time(Object *ob, ShaderFxData *fx)
+{
+	if (BKE_shaderfx_dependsOnTime(fx)) {
+		return true;
+	}
+
+	/* Check whether effect is animated. */
+	/* TODO (Aligorith): this should be handled as part of build_animdata() */
+	if (ob->adt) {
+		AnimData *adt = ob->adt;
+		FCurve *fcu;
+
+		char pattern[MAX_NAME + 32];
+		BLI_snprintf(pattern, sizeof(pattern), "shader_effects[\"%s\"]", fx->name);
+
+		/* action - check for F-Curves with paths containing string[' */
+		if (adt->action) {
+			for (fcu = (FCurve *)adt->action->curves.first;
+				fcu != NULL;
+				fcu = (FCurve *)fcu->next)
+			{
+				if (fcu->rna_path && strstr(fcu->rna_path, pattern))
+					return true;
+			}
+		}
+
+		/* This here allows properties to get driven and still update properly
+		*
+		*/
+		for (fcu = (FCurve *)adt->drivers.first;
+			fcu != NULL;
+			fcu = (FCurve *)fcu->next)
+		{
+			if (fcu->rna_path && strstr(fcu->rna_path, pattern))
+				return true;
+		}
+	}
+
+	return false;
+}
+
 /* set "ignore cache" flag for all caches on this object */
 static void object_cacheIgnoreClear(Object *ob, int state)
 {
diff --git a/source/blender/blenkernel/intern/object_deform.c b/source/blender/blenkernel/intern/object_deform.c
index 5c9e53aaa56..a6b0e57e55c 100644
--- a/source/blender/blenkernel/intern/object_deform.c
+++ b/source/blender/blenkernel/intern/object_deform.c
@@ -53,6 +53,7 @@
 #include "BKE_object.h"
 #include "BKE_mesh.h"
 #include "BKE_modifier.h"
+#include "BKE_gpencil.h"
 
 /** \name Misc helpers
  * \{ */
@@ -402,12 +403,17 @@ static void object_defgroup_remove_edit_mode(Object *ob, bDeformGroup *dg)
  */
 void BKE_object_defgroup_remove(Object *ob, bDeformGroup *defgroup)
 {
-	if (BKE_object_is_in_editmode_vgroup(ob))
-		object_defgroup_remove_edit_mode(ob, defgroup);
-	else
-		object_defgroup_remove_object_mode(ob, defgroup);
+	if ((ob) && (ob->type == OB_GPENCIL)) {
+		BKE_gpencil_vgroup_remove(ob, defgroup);
+	}
+	else {
+		if (BKE_object_is_in_editmode_vgroup(ob))
+			object_defgroup_remove_edit_mode(ob, defgroup);
+		else
+			object_defgroup_remove_object_mode(ob, defgroup);
 
-	BKE_mesh_batch_cache_dirty(ob->data, BKE_MESH_BATCH_DIRTY_ALL);
+		BKE_mesh_batch_cache_dirty(ob->data, BKE_MESH_BATCH_DIRTY_ALL);
+	}
 }
 
 /**
diff --git a/source/blender/blenkernel/intern/object_update.c b/source/blender/blenkernel/intern/object_update.c
index 3e72de3909f..3641df26496 100644
--- a/source/blender/blenkernel/intern/object_update.c
+++ b/source/blender/blenkernel/intern/object_update.c
@@ -62,6 +62,7 @@
 #include "BKE_particle.h"
 #include "BKE_pointcache.h"
 #include "BKE_scene.h"
+#include "BKE_gpencil.h"
 
 #include "MEM_guardedalloc.h"
 
@@ -324,6 +325,9 @@ void BKE_object_eval_uber_data(Depsgraph *depsgraph,
 		case OB_MBALL:
 			BKE_mball_batch_cache_dirty(ob->data, BKE_MBALL_BATCH_DIRTY_ALL);
 			break;
+		case OB_GPENCIL:
+			BKE_gpencil_batch_cache_dirty(ob->data);
+			break;
 	}
 }
 
diff --git a/source/blender/blenkernel/intern/paint.c b/source/blender/blenkernel/intern/paint.c
index 07aa21f44ff..cb26f7e9f3e 100644
--- a/source/blender/blenkernel/intern/paint.c
+++ b/source/blender/blenkernel/intern/paint.c
@@ -41,13 +41,19 @@
 #include "DNA_scene_types.h"
 #include "DNA_brush_types.h"
 #include "DNA_space_types.h"
+#include "DNA_gpencil_types.h"
 #include "DNA_workspace_types.h"
 
 #include "BLI_bitmap.h"
+#include "BLI_blenlib.h"
 #include "BLI_utildefines.h"
+#include "BLI_string_utils.h"
 #include "BLI_math_vector.h"
 #include "BLI_listbase.h"
 
+#include "BLT_translation.h"
+
+#include "BKE_animsys.h"
 #include "BKE_brush.h"
 #include "BKE_colortools.h"
 #include "BKE_deform.h"
@@ -55,6 +61,7 @@
 #include "BKE_context.h"
 #include "BKE_crazyspace.h"
 #include "BKE_global.h"
+#include "BKE_gpencil.h"
 #include "BKE_image.h"
 #include "BKE_key.h"
 #include "BKE_library.h"
@@ -151,6 +158,8 @@ Paint *BKE_paint_get_active_from_paintmode(Scene *sce, ePaintMode mode)
 				return &ts->imapaint.paint;
 			case ePaintSculptUV:
 				return &ts->uvsculpt->paint;
+			case ePaintGpencil:
+				return &ts->gp_paint->paint;
 			case ePaintInvalid:
 				return NULL;
 			default:
@@ -176,6 +185,8 @@ Paint *BKE_paint_get_active(Scene *sce, ViewLayer *view_layer)
 					return &ts->wpaint->paint;
 				case OB_MODE_TEXTURE_PAINT:
 					return &ts->imapaint.paint;
+				case OB_MODE_GPENCIL_PAINT:
+					return &ts->gp_paint->paint;
 				case OB_MODE_EDIT:
 					if (ts->use_uv_sculpt)
 						return &ts->uvsculpt->paint;
@@ -430,13 +441,11 @@ PaletteColor *BKE_palette_color_add(Palette *palette)
 	return color;
 }
 
-
 bool BKE_palette_is_empty(const struct Palette *palette)
 {
 	return BLI_listbase_is_empty(&palette->colors);
 }
 
-
 /* are we in vertex paint or weight pain face select mode? */
 bool BKE_paint_select_face_test(Object *ob)
 {
diff --git a/source/blender/blenkernel/intern/scene.c b/source/blender/blenkernel/intern/scene.c
index b50dc37af81..7085b515ec1 100644
--- a/source/blender/blenkernel/intern/scene.c
+++ b/source/blender/blenkernel/intern/scene.c
@@ -173,6 +173,10 @@ ToolSettings *BKE_toolsettings_copy(ToolSettings *toolsettings, const int flag)
 		ts->uvsculpt = MEM_dupallocN(ts->uvsculpt);
 		BKE_paint_copy(&ts->uvsculpt->paint, &ts->uvsculpt->paint, flag);
 	}
+	if (ts->gp_paint) {
+		ts->gp_paint = MEM_dupallocN(ts->gp_paint);
+		BKE_paint_copy(&ts->gp_paint->paint, &ts->gp_paint->paint, flag);
+	}
 
 	BKE_paint_copy(&ts->imapaint.paint, &ts->imapaint.paint, flag);
 	ts->imapaint.paintcursor = NULL;
@@ -180,15 +184,10 @@ ToolSettings *BKE_toolsettings_copy(ToolSettings *toolsettings, const int flag)
 	ts->particle.scene = NULL;
 	ts->particle.object = NULL;
 
-	/* duplicate Grease Pencil Drawing Brushes */
-	BLI_listbase_clear(&ts->gp_brushes);
-	for (bGPDbrush *brush = toolsettings->gp_brushes.first; brush; brush = brush->next) {
-		bGPDbrush *newbrush = BKE_gpencil_brush_duplicate(brush);
-		BLI_addtail(&ts->gp_brushes, newbrush);
-	}
-
 	/* duplicate Grease Pencil interpolation curve */
 	ts->gp_interpolate.custom_ipo = curvemapping_copy(ts->gp_interpolate.custom_ipo);
+	/* duplicate Grease Pencil multiframe fallof */
+	ts->gp_sculpt.cur_falloff = curvemapping_copy(ts->gp_sculpt.cur_falloff);
 	return ts;
 }
 
@@ -213,16 +212,20 @@ void BKE_toolsettings_free(ToolSettings *toolsettings)
 		BKE_paint_free(&toolsettings->uvsculpt->paint);
 		MEM_freeN(toolsettings->uvsculpt);
 	}
+	if (toolsettings->gp_paint) {
+		BKE_paint_free(&toolsettings->gp_paint->paint);
+		MEM_freeN(toolsettings->gp_paint);
+	}
 	BKE_paint_free(&toolsettings->imapaint.paint);
 
-	/* free Grease Pencil Drawing Brushes */
-	BKE_gpencil_free_brushes(&toolsettings->gp_brushes);
-	BLI_freelistN(&toolsettings->gp_brushes);
-
 	/* free Grease Pencil interpolation curve */
 	if (toolsettings->gp_interpolate.custom_ipo) {
 		curvemapping_free(toolsettings->gp_interpolate.custom_ipo);
 	}
+	/* free Grease Pencil multiframe falloff curve */
+	if (toolsettings->gp_sculpt.cur_falloff) {
+		curvemapping_free(toolsettings->gp_sculpt.cur_falloff);
+	}
 
 	MEM_freeN(toolsettings);
 }
@@ -428,9 +431,9 @@ Scene *BKE_scene_copy(Main *bmain, Scene *sce, int type)
 		}
 
 		/* NOTE: part of SCE_COPY_LINK_DATA and SCE_COPY_FULL operations
-		 * are done outside of blenkernel with ED_objects_single_users! */
+		 * are done outside of blenkernel with ED_object_single_users! */
 
-		/*  camera */
+		/*  camera   */
 		if (ELEM(type, SCE_COPY_LINK_DATA, SCE_COPY_FULL)) {
 			ID_NEW_REMAP(sce_copy->camera);
 		}
@@ -683,6 +686,19 @@ void BKE_scene_init(Scene *sce)
 	sce->toolsettings->imapaint.normal_angle = 80;
 	sce->toolsettings->imapaint.seam_bleed = 2;
 
+	/* alloc grease pencil drawing brushes */
+	sce->toolsettings->gp_paint = MEM_callocN(sizeof(GpPaint), "GpPaint");
+
+	/* grease pencil multiframe falloff curve */
+	sce->toolsettings->gp_sculpt.cur_falloff = curvemapping_add(1, 0.0f, 0.0f, 1.0f, 1.0f);
+	CurveMapping *gp_falloff_curve = sce->toolsettings->gp_sculpt.cur_falloff;
+	curvemapping_set_defaults(gp_falloff_curve, 1, 0.0f, 0.0f, 1.0f, 1.0f);
+	curvemapping_initialize(gp_falloff_curve);
+	curvemap_reset(gp_falloff_curve->cm,
+		&gp_falloff_curve->clipr,
+		CURVE_PRESET_GAUSS,
+		CURVEMAP_SLOPE_POSITIVE);
+
 	sce->physics_settings.gravity[0] = 0.0f;
 	sce->physics_settings.gravity[1] = 0.0f;
 	sce->physics_settings.gravity[2] = -9.81f;
@@ -760,46 +776,65 @@ void BKE_scene_init(Scene *sce)
 	{
 		GP_BrushEdit_Settings *gset = &sce->toolsettings->gp_sculpt;
 		GP_EditBrush_Data *gp_brush;
+		float curcolor_add[3], curcolor_sub[3];
+		ARRAY_SET_ITEMS(curcolor_add, 1.0f, 0.6f, 0.6f);
+		ARRAY_SET_ITEMS(curcolor_sub, 0.6f, 0.6f, 1.0f);
 
 		gp_brush = &gset->brush[GP_EDITBRUSH_TYPE_SMOOTH];
 		gp_brush->size = 25;
 		gp_brush->strength = 0.3f;
-		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF | GP_EDITBRUSH_FLAG_SMOOTH_PRESSURE;
+		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF | GP_EDITBRUSH_FLAG_SMOOTH_PRESSURE | GP_EDITBRUSH_FLAG_ENABLE_CURSOR;
+		copy_v3_v3(gp_brush->curcolor_add, curcolor_add);
+		copy_v3_v3(gp_brush->curcolor_sub, curcolor_sub);
 
 		gp_brush = &gset->brush[GP_EDITBRUSH_TYPE_THICKNESS];
 		gp_brush->size = 25;
 		gp_brush->strength = 0.5f;
-		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF;
+		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF | GP_EDITBRUSH_FLAG_ENABLE_CURSOR;
+		copy_v3_v3(gp_brush->curcolor_add, curcolor_add);
+		copy_v3_v3(gp_brush->curcolor_sub, curcolor_sub);
 
 		gp_brush = &gset->brush[GP_EDITBRUSH_TYPE_STRENGTH];
 		gp_brush->size = 25;
 		gp_brush->strength = 0.5f;
-		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF;
+		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF | GP_EDITBRUSH_FLAG_ENABLE_CURSOR;
+		copy_v3_v3(gp_brush->curcolor_add, curcolor_add);
+		copy_v3_v3(gp_brush->curcolor_sub, curcolor_sub);
 
 		gp_brush = &gset->brush[GP_EDITBRUSH_TYPE_GRAB];
 		gp_brush->size = 50;
 		gp_brush->strength = 0.3f;
-		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF;
+		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF | GP_EDITBRUSH_FLAG_ENABLE_CURSOR;
+		copy_v3_v3(gp_brush->curcolor_add, curcolor_add);
+		copy_v3_v3(gp_brush->curcolor_sub, curcolor_sub);
 
 		gp_brush = &gset->brush[GP_EDITBRUSH_TYPE_PUSH];
 		gp_brush->size = 25;
 		gp_brush->strength = 0.3f;
-		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF;
+		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF | GP_EDITBRUSH_FLAG_ENABLE_CURSOR;
+		copy_v3_v3(gp_brush->curcolor_add, curcolor_add);
+		copy_v3_v3(gp_brush->curcolor_sub, curcolor_sub);
 
 		gp_brush = &gset->brush[GP_EDITBRUSH_TYPE_TWIST];
 		gp_brush->size = 50;
 		gp_brush->strength = 0.3f; // XXX?
-		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF;
+		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF | GP_EDITBRUSH_FLAG_ENABLE_CURSOR;
+		copy_v3_v3(gp_brush->curcolor_add, curcolor_add);
+		copy_v3_v3(gp_brush->curcolor_sub, curcolor_sub);
 
 		gp_brush = &gset->brush[GP_EDITBRUSH_TYPE_PINCH];
 		gp_brush->size = 50;
 		gp_brush->strength = 0.5f; // XXX?
-		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF;
+		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF | GP_EDITBRUSH_FLAG_ENABLE_CURSOR;
+		copy_v3_v3(gp_brush->curcolor_add, curcolor_add);
+		copy_v3_v3(gp_brush->curcolor_sub, curcolor_sub);
 
 		gp_brush = &gset->brush[GP_EDITBRUSH_TYPE_RANDOMIZE];
 		gp_brush->size = 25;
 		gp_brush->strength = 0.5f;
-		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF;
+		gp_brush->flag = GP_EDITBRUSH_FLAG_USE_FALLOFF | GP_EDITBRUSH_FLAG_ENABLE_CURSOR;
+		copy_v3_v3(gp_brush->curcolor_add, curcolor_add);
+		copy_v3_v3(gp_brush->curcolor_sub, curcolor_sub);
 	}
 
 	/* GP Stroke Placement */
@@ -808,6 +843,10 @@ void BKE_scene_init(Scene *sce)
 	sce->toolsettings->gpencil_seq_align = GP_PROJECT_VIEWSPACE;
 	sce->toolsettings->gpencil_ima_align = GP_PROJECT_VIEWSPACE;
 
+	/* Annotations */
+	sce->toolsettings->annotate_v3d_align = GP_PROJECT_VIEWSPACE | GP_PROJECT_CURSOR;
+	sce->toolsettings->annotate_thickness = 3;
+
 	sce->orientation_index_custom = -1;
 
 	/* Master Collection */
diff --git a/source/blender/blenkernel/intern/shader_fx.c b/source/blender/blenkernel/intern/shader_fx.c
new file mode 100644
index 00000000000..c028c2184fd
--- /dev/null
+++ b/source/blender/blenkernel/intern/shader_fx.c
@@ -0,0 +1,245 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2018, Blender Foundation
+ * This is a new part of Blender
+ *
+ * Contributor(s): Antonio Vazquez
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file blender/blenkernel/intern/shader_fx.c
+ *  \ingroup bke
+ */
+
+
+#include <stdio.h>
+
+#include "MEM_guardedalloc.h"
+
+#include "BLI_blenlib.h"
+#include "BLI_utildefines.h"
+#include "BLI_math_vector.h"
+#include "BLI_string_utils.h"
+
+#include "BLT_translation.h"
+
+#include "DNA_meshdata_types.h"
+#include "DNA_scene_types.h"
+#include "DNA_object_types.h"
+#include "DNA_gpencil_types.h"
+#include "DNA_shader_fx_types.h"
+
+#include "BKE_global.h"
+#include "BKE_library.h"
+#include "BKE_library_query.h"
+#include "BKE_gpencil.h"
+#include "BKE_shader_fx.h"
+#include "BKE_object.h"
+
+#include "DEG_depsgraph.h"
+#include "DEG_depsgraph_query.h"
+
+#include "FX_shader_types.h"
+
+static ShaderFxTypeInfo *shader_fx_types[NUM_SHADER_FX_TYPES] = { NULL };
+
+/* *************************************************** */
+/* Methods - Evaluation Loops, etc. */
+
+/* check if exist grease pencil effects */
+bool BKE_shaderfx_has_gpencil(Object *ob)
+{
+	ShaderFxData *fx;
+	for (fx = ob->shader_fx.first; fx; fx = fx->next) {
+		const ShaderFxTypeInfo *fxi = BKE_shaderfxType_getInfo(fx->type);
+		if (fxi->type == eShaderFxType_GpencilType) {
+			return true;
+		}
+	}
+	return false;
+}
+
+void BKE_shaderfx_init(void)
+{
+	/* Initialize shaders */
+	shaderfx_type_init(shader_fx_types); /* FX_shader_util.c */
+}
+
+ShaderFxData *BKE_shaderfx_new(int type)
+{
+	const ShaderFxTypeInfo *fxi = BKE_shaderfxType_getInfo(type);
+	ShaderFxData *fx = MEM_callocN(fxi->struct_size, fxi->struct_name);
+
+	/* note, this name must be made unique later */
+	BLI_strncpy(fx->name, DATA_(fxi->name), sizeof(fx->name));
+
+	fx->type = type;
+	fx->mode = eShaderFxMode_Realtime | eShaderFxMode_Render | eShaderFxMode_Expanded;
+	fx->flag = eShaderFxFlag_StaticOverride_Local;
+
+	if (fxi->flags & eShaderFxTypeFlag_EnableInEditmode)
+		fx->mode |= eShaderFxMode_Editmode;
+
+	if (fxi->initData) fxi->initData(fx);
+
+	return fx;
+}
+
+static void shaderfx_free_data_id_us_cb(void *UNUSED(userData), Object *UNUSED(ob), ID **idpoin, int cb_flag)
+{
+	ID *id = *idpoin;
+	if (id != NULL && (cb_flag & IDWALK_CB_USER) != 0) {
+		id_us_min(id);
+	}
+}
+
+void BKE_shaderfx_free_ex(ShaderFxData *fx, const int flag)
+{
+	const ShaderFxTypeInfo *fxi = BKE_shaderfxType_getInfo(fx->type);
+
+	if ((flag & LIB_ID_CREATE_NO_USER_REFCOUNT) == 0) {
+		if (fxi->foreachIDLink) {
+			fxi->foreachIDLink(fx, NULL, shaderfx_free_data_id_us_cb, NULL);
+		}
+		else if (fxi->foreachObjectLink) {
+			fxi->foreachObjectLink(fx, NULL, (ShaderFxObjectWalkFunc)shaderfx_free_data_id_us_cb, NULL);
+		}
+	}
+
+	if (fxi->freeData) fxi->freeData(fx);
+	if (fx->error) MEM_freeN(fx->error);
+
+	MEM_freeN(fx);
+}
+
+void BKE_shaderfx_free(ShaderFxData *fx)
+{
+	BKE_shaderfx_free_ex(fx, 0);
+}
+
+/* check unique name */
+bool BKE_shaderfx_unique_name(ListBase *shaders, ShaderFxData *fx)
+{
+	if (shaders && fx) {
+		const ShaderFxTypeInfo *fxi = BKE_shaderfxType_getInfo(fx->type);
+		return BLI_uniquename(shaders, fx, DATA_(fxi->name), '.', offsetof(ShaderFxData, name), sizeof(fx->name));
+	}
+	return false;
+}
+
+bool BKE_shaderfx_dependsOnTime(ShaderFxData *fx)
+{
+	const ShaderFxTypeInfo *fxi = BKE_shaderfxType_getInfo(fx->type);
+
+	return fxi->dependsOnTime && fxi->dependsOnTime(fx);
+}
+
+const ShaderFxTypeInfo *BKE_shaderfxType_getInfo(ShaderFxType type)
+{
+	/* type unsigned, no need to check < 0 */
+	if (type < NUM_SHADER_FX_TYPES && shader_fx_types[type]->name[0] != '\0') {
+		return shader_fx_types[type];
+	}
+	else {
+		return NULL;
+	}
+}
+
+void BKE_shaderfx_copyData_generic(const ShaderFxData *fx_src, ShaderFxData *fx_dst)
+{
+	const ShaderFxTypeInfo *fxi = BKE_shaderfxType_getInfo(fx_src->type);
+
+	/* fx_dst may have alredy be fully initialized with some extra allocated data,
+	* we need to free it now to avoid memleak. */
+	if (fxi->freeData) {
+		fxi->freeData(fx_dst);
+	}
+
+	const size_t data_size = sizeof(ShaderFxData);
+	const char *fx_src_data = ((const char *)fx_src) + data_size;
+	char       *fx_dst_data = ((char *)fx_dst) + data_size;
+	BLI_assert(data_size <= (size_t)fxi->struct_size);
+	memcpy(fx_dst_data, fx_src_data, (size_t)fxi->struct_size - data_size);
+}
+
+static void shaderfx_copy_data_id_us_cb(void *UNUSED(userData), Object *UNUSED(ob), ID **idpoin, int cb_flag)
+{
+	ID *id = *idpoin;
+	if (id != NULL && (cb_flag & IDWALK_CB_USER) != 0) {
+		id_us_plus(id);
+	}
+}
+
+void BKE_shaderfx_copyData_ex(ShaderFxData *fx, ShaderFxData *target, const int flag)
+{
+	const ShaderFxTypeInfo *fxi = BKE_shaderfxType_getInfo(fx->type);
+
+	target->mode = fx->mode;
+	target->flag = fx->flag;
+
+	if (fxi->copyData) {
+		fxi->copyData(fx, target);
+	}
+
+	if ((flag & LIB_ID_CREATE_NO_USER_REFCOUNT) == 0) {
+		if (fxi->foreachIDLink) {
+			fxi->foreachIDLink(target, NULL, shaderfx_copy_data_id_us_cb, NULL);
+		}
+		else if (fxi->foreachObjectLink) {
+			fxi->foreachObjectLink(target, NULL, (ShaderFxObjectWalkFunc)shaderfx_copy_data_id_us_cb, NULL);
+		}
+	}
+}
+
+void BKE_shaderfx_copyData(ShaderFxData *fx, ShaderFxData *target)
+{
+	BKE_shaderfx_copyData_ex(fx, target, 0);
+}
+
+ShaderFxData *BKE_shaderfx_findByType(Object *ob, ShaderFxType type)
+{
+	ShaderFxData *fx = ob->shader_fx.first;
+
+	for (; fx; fx = fx->next)
+		if (fx->type == type)
+			break;
+
+	return fx;
+}
+
+void BKE_shaderfx_foreachIDLink(Object *ob, ShaderFxIDWalkFunc walk, void *userData)
+{
+	ShaderFxData *fx = ob->shader_fx.first;
+
+	for (; fx; fx = fx->next) {
+		const ShaderFxTypeInfo *fxi = BKE_shaderfxType_getInfo(fx->type);
+
+		if (fxi->foreachIDLink) fxi->foreachIDLink(fx, ob, walk, userData);
+		else if (fxi->foreachObjectLink) {
+			/* each Object can masquerade as an ID, so this should be OK */
+			ShaderFxObjectWalkFunc fp = (ShaderFxObjectWalkFunc)walk;
+			fxi->foreachObjectLink(fx, ob, fp, userData);
+		}
+	}
+}
+
+ShaderFxData *BKE_shaderfx_findByName(Object *ob, const char *name)
+{
+	return BLI_findstring(&(ob->shader_fx), name, offsetof(ShaderFxData, name));
+}