Sculpt Vertex Colors: Initial implementation

Sculpt Vertex Colors is a painting system that runs inside sculpt mode, reusing all its tools and optimizations. This provides much better performance, easier to maintain code and more advanced features (new brush engine, filters, symmetry options, masks and face sets compatibility...). This is also the initial step for future features like vertex painting in Multires and brushes that can sculpt and paint at the same time.

This commit includes:
  - SCULPT_UNDO_COLOR for undo support in sculpt mode
  - SCULPT_UPDATE_COLOR and PBVH flags and rendering
  - Sculpt Color API functions
  - Sculpt capability for sculpt tools (only enabled in the Paint Brush for now)
  - Rendering support in workbench (default to Sculpt Vertex Colors except in Vertex Paint)
  - Conversion operator between MPropCol (Sculpt Vertex Colors) and MLoopCol (Vertex Paint)
  - Remesher reprojection in the Voxel Remehser
  - Paint Brush and Smear Brush with color smoothing in alt-smooth mode
  - Parameters for the new brush engine (density, opacity, flow, wet paint mixing, tip scale) implemented in Sculpt Vertex Colors
  - Color Filter
  - Color picker (uses S shortcut, replaces smooth)
  - Color selector in the top bar

Reviewed By: brecht

Maniphest Tasks: T72866

Differential Revision: https://developer.blender.org/D5975

1 files changed, 29 insertions, 1 deletions

diff --git a/source/blender/editors/sculpt_paint/sculpt_intern.h b/source/blender/editors/sculpt_paint/sculpt_intern.h
index 0e27658e848..6d1315db723 100644
--- a/source/blender/editors/sculpt_paint/sculpt_intern.h
+++ b/source/blender/editors/sculpt_paint/sculpt_intern.h
@@ -27,6 +27,7 @@
 #include "DNA_brush_types.h"
 #include "DNA_key_types.h"
 #include "DNA_listBase.h"
+#include "DNA_meshdata_types.h"
 #include "DNA_vec_types.h"
 
 #include "BLI_bitmap.h"
@@ -56,6 +57,7 @@ typedef enum SculptUpdateType {
   SCULPT_UPDATE_COORDS = 1 << 0,
   SCULPT_UPDATE_MASK = 1 << 1,
   SCULPT_UPDATE_VISIBILITY = 1 << 2,
+  SCULPT_UPDATE_COLOR = 1 << 3,
 } SculptUpdateType;
 
 void SCULPT_flush_update_step(bContext *C, SculptUpdateType update_flags);
@@ -92,6 +94,7 @@ int SCULPT_vertex_count_get(struct SculptSession *ss);
 const float *SCULPT_vertex_co_get(struct SculptSession *ss, int index);
 void SCULPT_vertex_normal_get(SculptSession *ss, int index, float no[3]);
 float SCULPT_vertex_mask_get(struct SculptSession *ss, int index);
+const float *SCULPT_vertex_color_get(SculptSession *ss, int index);
 
 #define SCULPT_VERTEX_NEIGHBOR_FIXED_CAPACITY 256
 typedef struct SculptVertexNeighborIter {
@@ -179,15 +182,20 @@ typedef struct {
   float (*coords)[3];
   short (*normals)[3];
   const float *vmasks;
+  float (*colors)[4];
 
   /* Original coordinate, normal, and mask. */
   const float *co;
   const short *no;
   float mask;
+  const float *col;
 } SculptOrigVertData;
 
 void SCULPT_orig_vert_data_init(SculptOrigVertData *data, Object *ob, PBVHNode *node);
 void SCULPT_orig_vert_data_update(SculptOrigVertData *orig_data, PBVHVertexIter *iter);
+void SCULPT_orig_vert_data_unode_init(SculptOrigVertData *data,
+                                      Object *ob,
+                                      struct SculptUndoNode *unode);
 
 /* Utils. */
 void SCULPT_calc_brush_plane(struct Sculpt *sd,
@@ -305,7 +313,7 @@ float *SCULPT_boundary_automasking_init(Object *ob,
                                         float *automask_factor);
 
 /* Filters. */
-void SCULPT_filter_cache_init(Object *ob, Sculpt *sd);
+void SCULPT_filter_cache_init(Object *ob, Sculpt *sd, const int undo_type);
 void SCULPT_filter_cache_free(SculptSession *ss);
 
 void SCULPT_mask_filter_smooth_apply(
@@ -374,6 +382,12 @@ void SCULPT_multiplane_scrape_preview_draw(const uint gpuattr,
 /* Draw Face Sets Brush. */
 void SCULPT_do_draw_face_sets_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode);
 
+/* Paint Brush. */
+void SCULPT_do_paint_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode);
+
+/* Smear Brush. */
+void SCULPT_do_smear_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode);
+
 /* Smooth Brush. */
 
 void SCULPT_neighbor_average(SculptSession *ss, float avg[3], uint vert);
@@ -383,6 +397,7 @@ void SCULPT_bmesh_four_neighbor_average(float avg[3], float direction[3], struct
 
 void SCULPT_neighbor_coords_average(SculptSession *ss, float result[3], int index);
 float SCULPT_neighbor_mask_average(SculptSession *ss, int index);
+void SCULPT_neighbor_color_average(SculptSession *ss, float result[4], int index);
 
 void SCULPT_smooth(Sculpt *sd,
                    Object *ob,
@@ -427,6 +442,7 @@ typedef enum {
   SCULPT_UNDO_DYNTOPO_SYMMETRIZE,
   SCULPT_UNDO_GEOMETRY,
   SCULPT_UNDO_FACE_SETS,
+  SCULPT_UNDO_COLOR,
 } SculptUndoType;
 
 /* Storage of geometry for the undo node.
@@ -457,6 +473,7 @@ typedef struct SculptUndoNode {
   float (*co)[3];
   float (*orig_co)[3];
   short (*no)[3];
+  float (*col)[4];
   float *mask;
   int totvert;
 
@@ -568,6 +585,8 @@ typedef struct SculptThreadedTaskData {
 
   bool any_vertex_sampled;
 
+  float *wet_mix_sampled_color;
+
   float *prev_mask;
 
   float *pose_factor;
@@ -601,6 +620,7 @@ typedef struct SculptThreadedTaskData {
   bool dirty_mask_dirty_only;
 
   int face_set;
+  int filter_undo_type;
 
   ThreadMutex mutex;
 
@@ -720,6 +740,8 @@ typedef struct StrokeCache {
   float bstrength;
   float normal_weight; /* from brush (with optional override) */
 
+  float (*prev_colors)[4];
+
   /* The rest is temporary storage that isn't saved as a property */
 
   bool first_time; /* Beginning of stroke may do some things special */
@@ -813,6 +835,9 @@ typedef struct StrokeCache {
   float stroke_local_mat[4][4];
   float multiplane_scrape_angle;
 
+  float wet_mix_prev_color[4];
+  float density_seed;
+
   rcti previous_r; /* previous redraw rectangle */
   rcti current_r;  /* current redraw rectangle */
 
@@ -901,6 +926,9 @@ void SCULPT_OT_mesh_filter(struct wmOperatorType *ot);
 /* Cloth Filter. */
 void SCULPT_OT_cloth_filter(struct wmOperatorType *ot);
 
+/* Color Filter. */
+void SCULPT_OT_color_filter(struct wmOperatorType *ot);
+
 /* Mask filter and Dirty Mask. */
 void SCULPT_OT_mask_filter(struct wmOperatorType *ot);
 void SCULPT_OT_dirty_mask(struct wmOperatorType *ot);