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.

6 files changed, 41 insertions, 13 deletions

diff --git a/source/blender/editors/animation/anim_channels_defines.c b/source/blender/editors/animation/anim_channels_defines.c
index 3c10cda6456..2431bd50e1b 100644
--- a/source/blender/editors/animation/anim_channels_defines.c
+++ b/source/blender/editors/animation/anim_channels_defines.c
@@ -64,6 +64,7 @@
 
 #include "BKE_animsys.h"
 #include "BKE_curve.h"
+#include "BKE_gpencil.h"
 #include "BKE_key.h"
 #include "BKE_main.h"
 #include "BKE_nla.h"
@@ -83,6 +84,8 @@
 
 #include "BIF_gl.h"
 
+#include "DEG_depsgraph.h"
+
 #include "WM_api.h"
 #include "WM_types.h"
 
@@ -661,6 +664,8 @@ static int acf_object_icon(bAnimListElem *ale)
 			return ICON_OUTLINER_OB_SURFACE;
 		case OB_EMPTY:
 			return ICON_OUTLINER_OB_EMPTY;
+		case OB_GPENCIL:
+			return ICON_OUTLINER_OB_GREASEPENCIL;
 		default:
 			return ICON_OBJECT_DATA;
 	}
@@ -4048,8 +4053,16 @@ static void achannel_setting_flush_widget_cb(bContext *C, void *ale_npoin, void
 		return;
 	}
 
-	if (ale_setting->type == ANIMTYPE_GPLAYER)
+	if (ale_setting->type == ANIMTYPE_GPLAYER) {
+		/* draw cache updates for settings that affect the visible strokes */
+		if (setting == ACHANNEL_SETTING_VISIBLE) {
+			bGPdata *gpd = (bGPdata *)ale_setting->id;
+			DEG_id_tag_update(&gpd->id, OB_RECALC_OB | OB_RECALC_DATA);
+		}
+
+		/* UI updates */
 		WM_event_add_notifier(C, NC_GPENCIL | ND_DATA, NULL);
+	}
 
 	/* tag copy-on-write flushing (so that the settings will have an effect) */
 	if (ale_setting->id) {
diff --git a/source/blender/editors/animation/anim_channels_edit.c b/source/blender/editors/animation/anim_channels_edit.c
index d768be49ad4..3f22ac6fa3a 100644
--- a/source/blender/editors/animation/anim_channels_edit.c
+++ b/source/blender/editors/animation/anim_channels_edit.c
@@ -1727,8 +1727,7 @@ static int animchannels_delete_exec(bContext *C, wmOperator *UNUSED(op))
 				bGPDlayer *gpl = (bGPDlayer *)ale->data;
 
 				/* try to delete the layer's data and the layer itself */
-				BKE_gpencil_free_frames(gpl);
-				BLI_freelinkN(&gpd->layers, gpl);
+				BKE_gpencil_layer_delete(gpd, gpl);
 				break;
 			}
 			case ANIMTYPE_MASKLAYER:
diff --git a/source/blender/editors/animation/anim_deps.c b/source/blender/editors/animation/anim_deps.c
index adb5a10c19d..898c8b6464a 100644
--- a/source/blender/editors/animation/anim_deps.c
+++ b/source/blender/editors/animation/anim_deps.c
@@ -435,6 +435,16 @@ void ANIM_animdata_update(bAnimContext *ac, ListBase *anim_data)
 				ANIM_list_elem_update(ac->bmain, ac->scene, ale);
 			}
 		}
+		else if (ale->update) {
+#if 0
+			if (G.debug & G_DEBUG) {
+				printf("%s: Unhandled animchannel updates (%d) for type=%d (%p)\n",
+				       __func__, ale->update, ale->type, ale->data);
+			}
+#endif
+			/* Prevent crashes in cases where it can't be handled */
+			ale->update = 0;
+		}
 
 		BLI_assert(ale->update == 0);
 	}
diff --git a/source/blender/editors/animation/anim_draw.c b/source/blender/editors/animation/anim_draw.c
index 780e984f870..05ea3fd6314 100644
--- a/source/blender/editors/animation/anim_draw.c
+++ b/source/blender/editors/animation/anim_draw.c
@@ -552,11 +552,11 @@ static bool find_prev_next_keyframes(struct bContext *C, int *nextfra, int *prev
 
 	/* populate tree with keyframe nodes */
 	scene_to_keylist(&ads, scene, &keys, NULL);
-	gpencil_to_keylist(&ads, scene->gpd, &keys);
+	gpencil_to_keylist(&ads, scene->gpd, &keys, false);
 
 	if (ob) {
 		ob_to_keylist(&ads, ob, &keys, NULL);
-		gpencil_to_keylist(&ads, ob->gpd, &keys);
+		gpencil_to_keylist(&ads, ob->data, &keys, false);
 	}
 
 	if (mask) {
diff --git a/source/blender/editors/animation/anim_filter.c b/source/blender/editors/animation/anim_filter.c
index c59d24bbdf8..1981814eb02 100644
--- a/source/blender/editors/animation/anim_filter.c
+++ b/source/blender/editors/animation/anim_filter.c
@@ -72,6 +72,7 @@
 #include "DNA_speaker_types.h"
 #include "DNA_world_types.h"
 #include "DNA_gpencil_types.h"
+#include "DNA_brush_types.h"
 #include "DNA_object_types.h"
 #include "DNA_userdef_types.h"
 #include "DNA_layer_types.h"
@@ -1660,7 +1661,7 @@ static size_t animdata_filter_gpencil_data(ListBase *anim_data, bDopeSheet *ads,
 	 */
 	if (filter_mode & ANIMFILTER_ANIMDATA) {
 		/* just add GPD as a channel - this will add everything needed */
-		ANIMCHANNEL_NEW_CHANNEL(gpd, ANIMTYPE_GPDATABLOCK, NULL);
+		ANIMCHANNEL_NEW_CHANNEL(gpd, ANIMTYPE_GPDATABLOCK, gpd);
 	}
 	else {
 		ListBase tmp_data = {NULL, NULL};
@@ -1711,7 +1712,7 @@ static size_t animdata_filter_gpencil(bAnimContext *ac, ListBase *anim_data, voi
 		/* Objects in the scene */
 		for (base = view_layer->object_bases.first; base; base = base->next) {
 			/* Only consider this object if it has got some GP data (saving on all the other tests) */
-			if (base->object && base->object->gpd) {
+			if (base->object && (base->object->type == OB_GPENCIL)) {
 				Object *ob = base->object;
 
 				/* firstly, check if object can be included, by the following factors:
@@ -1748,7 +1749,7 @@ static size_t animdata_filter_gpencil(bAnimContext *ac, ListBase *anim_data, voi
 
 				/* finally, include this object's grease pencil datablock */
 				/* XXX: Should we store these under expanders per item? */
-				items += animdata_filter_gpencil_data(anim_data, ads, ob->gpd, filter_mode);
+				items += animdata_filter_gpencil_data(anim_data, ads, ob->data, filter_mode);
 			}
 		}
 	}
@@ -2613,8 +2614,10 @@ static size_t animdata_filter_dopesheet_ob(bAnimContext *ac, ListBase *anim_data
 		}
 
 		/* grease pencil */
-		if ((ob->gpd) && !(ads->filterflag & ADS_FILTER_NOGPENCIL)) {
-			tmp_items += animdata_filter_ds_gpencil(ac, &tmp_data, ads, ob->gpd, filter_mode);
+		if ((ob->type == OB_GPENCIL) &&
+			(ob->data) && !(ads->filterflag & ADS_FILTER_NOGPENCIL))
+		{
+			tmp_items += animdata_filter_ds_gpencil(ac, &tmp_data, ads, ob->data, filter_mode);
 		}
 	}
 	END_ANIMFILTER_SUBCHANNELS;
diff --git a/source/blender/editors/animation/keyframes_draw.c b/source/blender/editors/animation/keyframes_draw.c
index 30130ce4dac..a8b63e01ac1 100644
--- a/source/blender/editors/animation/keyframes_draw.c
+++ b/source/blender/editors/animation/keyframes_draw.c
@@ -48,6 +48,7 @@
 #include "DNA_object_types.h"
 #include "DNA_scene_types.h"
 #include "DNA_gpencil_types.h"
+#include "DNA_brush_types.h"
 #include "DNA_mask_types.h"
 
 #include "BKE_fcurve.h"
@@ -783,7 +784,7 @@ void draw_gpencil_channel(View2D *v2d, bDopeSheet *ads, bGPdata *gpd, float ypos
 
 	BLI_dlrbTree_init(&keys);
 
-	gpencil_to_keylist(ads, gpd, &keys);
+	gpencil_to_keylist(ads, gpd, &keys, false);
 
 	BLI_dlrbTree_linkedlist_sync(&keys);
 
@@ -1019,7 +1020,7 @@ void action_to_keylist(AnimData *adt, bAction *act, DLRBT_Tree *keys, DLRBT_Tree
 }
 
 
-void gpencil_to_keylist(bDopeSheet *ads, bGPdata *gpd, DLRBT_Tree *keys)
+void gpencil_to_keylist(bDopeSheet *ads, bGPdata *gpd, DLRBT_Tree *keys, const bool active)
 {
 	bGPDlayer *gpl;
 
@@ -1027,7 +1028,9 @@ void gpencil_to_keylist(bDopeSheet *ads, bGPdata *gpd, DLRBT_Tree *keys)
 		/* for now, just aggregate out all the frames, but only for visible layers */
 		for (gpl = gpd->layers.first; gpl; gpl = gpl->next) {
 			if ((gpl->flag & GP_LAYER_HIDE) == 0) {
-				gpl_to_keylist(ads, gpl, keys);
+				if ((!active) || ((active) && (gpl->flag & GP_LAYER_SELECT))) {
+					gpl_to_keylist(ads, gpl, keys);
+				}
 			}
 		}
 	}