Tool System: use tool type enum to access brushes

Previously the brush names were used which had the limit that:

- Brush names that were deleted wouldn't show up in the toolbar.
- Naming collisions between user defined brushes and existing tools
  broke tool selection.

Now brushes are created as needed when tools are selected.

Note, vertex/weight paint combine tool and blend modes,
this should be split out into a separate enum.

7 files changed, 103 insertions, 17 deletions

diff --git a/source/blender/blenkernel/BKE_paint.h b/source/blender/blenkernel/BKE_paint.h
index 6dcd3a7c446..dc05642fb69 100644
--- a/source/blender/blenkernel/BKE_paint.h
+++ b/source/blender/blenkernel/BKE_paint.h
@@ -33,10 +33,12 @@
  */
 
 struct bContext;
+struct bToolRef;
 struct BMesh;
 struct BMFace;
 struct Brush;
 struct CurveMapping;
+struct EnumPropertyItem;
 struct MeshElemMap;
 struct GridPaintMask;
 struct Main;
@@ -136,9 +138,11 @@ void BKE_paint_cavity_curve_preset(struct Paint *p, int preset);
 
 eObjectMode BKE_paint_object_mode_from_paint_mode(ePaintMode mode);
 struct Paint *BKE_paint_get_active_from_paintmode(struct Scene *sce, ePaintMode mode);
+const struct EnumPropertyItem *BKE_paint_get_tool_enum_from_paintmode(ePaintMode mode);
 struct Paint *BKE_paint_get_active(struct Scene *sce, struct ViewLayer *view_layer);
 struct Paint *BKE_paint_get_active_from_context(const struct bContext *C);
 ePaintMode BKE_paintmode_get_active_from_context(const struct bContext *C);
+ePaintMode BKE_paintmode_get_from_tool(const struct bToolRef *tref);
 struct Brush *BKE_paint_brush(struct Paint *paint);
 void BKE_paint_brush_set(struct Paint *paint, struct Brush *br);
 struct Palette *BKE_paint_palette(struct Paint *paint);
@@ -179,6 +183,7 @@ void BKE_paint_toolslots_len_ensure(struct Paint *paint, int len);
 void BKE_paint_toolslots_brush_update_ex(struct Paint *paint, struct Brush *brush);
 void BKE_paint_toolslots_brush_update(struct Paint *paint);
 void BKE_paint_toolslots_brush_validate(struct Main *bmain, struct Paint *paint);
+struct Brush *BKE_paint_toolslots_brush_get(struct Paint *paint, int slot_index);
 
 /* Used for both vertex color and weight paint */
 struct SculptVertexPaintGeomMap {
diff --git a/source/blender/blenkernel/intern/paint.c b/source/blender/blenkernel/intern/paint.c
index f12e33344dc..6bc86f75d71 100644
--- a/source/blender/blenkernel/intern/paint.c
+++ b/source/blender/blenkernel/intern/paint.c
@@ -79,6 +79,8 @@
 #include "DEG_depsgraph.h"
 #include "DEG_depsgraph_query.h"
 
+#include "RNA_enum_types.h"
+
 #include "bmesh.h"
 
 const char PAINT_CURSOR_SCULPT[3] = {255, 100, 100};
@@ -172,6 +174,28 @@ Paint *BKE_paint_get_active_from_paintmode(Scene *sce, ePaintMode mode)
 	return NULL;
 }
 
+const EnumPropertyItem *BKE_paint_get_tool_enum_from_paintmode(ePaintMode mode)
+{
+	switch (mode) {
+		case ePaintSculpt:
+			return rna_enum_brush_sculpt_tool_items;
+		case ePaintVertex:
+			return rna_enum_brush_vertex_tool_items;
+		case ePaintWeight:
+			return rna_enum_brush_vertex_tool_items;
+		case ePaintTextureProjective:
+		case ePaintTexture2D:
+			return rna_enum_brush_image_tool_items;
+		case ePaintSculptUV:
+			return NULL;
+		case ePaintGpencil:
+			return rna_enum_brush_gpencil_types_items;
+		case ePaintInvalid:
+			break;
+	}
+	return NULL;
+}
+
 Paint *BKE_paint_get_active(Scene *sce, ViewLayer *view_layer)
 {
 	if (sce && view_layer) {
@@ -288,6 +312,32 @@ ePaintMode BKE_paintmode_get_active_from_context(const bContext *C)
 	return ePaintInvalid;
 }
 
+ePaintMode BKE_paintmode_get_from_tool(const struct bToolRef *tref)
+{
+	if (tref->space_type == SPACE_VIEW3D) {
+		switch (tref->mode) {
+			case CTX_MODE_SCULPT:
+				return ePaintSculpt;
+			case CTX_MODE_PAINT_VERTEX:
+				return ePaintVertex;
+			case CTX_MODE_PAINT_WEIGHT:
+				return ePaintWeight;
+			case CTX_MODE_GPENCIL_PAINT:
+				return ePaintGpencil;
+			case CTX_MODE_PAINT_TEXTURE:
+				return ePaintTextureProjective;
+		}
+	}
+	else if (tref->space_type == SPACE_IMAGE) {
+		switch (tref->mode) {
+			case SI_MODE_PAINT:
+				return ePaintTexture2D;
+		}
+	}
+
+	return ePaintInvalid;
+}
+
 Brush *BKE_paint_brush(Paint *p)
 {
 	return p ? p->brush : NULL;
diff --git a/source/blender/blenkernel/intern/paint_toolslots.c b/source/blender/blenkernel/intern/paint_toolslots.c
index 61e0f03ce9e..c0f26c1c9c1 100644
--- a/source/blender/blenkernel/intern/paint_toolslots.c
+++ b/source/blender/blenkernel/intern/paint_toolslots.c
@@ -22,6 +22,8 @@
  *  \ingroup bke
  */
 
+#include <limits.h>
+
 #include "MEM_guardedalloc.h"
 
 #include "DNA_modifier_types.h"
@@ -36,6 +38,8 @@
 
 void BKE_paint_toolslots_len_ensure(Paint *paint, int len)
 {
+	/* Tool slots are 'uchar'. */
+	BLI_assert(len <= UCHAR_MAX);
 	if (paint->tool_slots_len < len) {
 		paint->tool_slots = MEM_recallocN(paint->tool_slots, sizeof(*paint->tool_slots) * len);
 		paint->tool_slots_len = len;
@@ -122,3 +126,12 @@ void BKE_paint_toolslots_brush_validate(Main *bmain, Paint *paint)
 	/* Fill slots from brushes. */
 	paint_toolslots_init(bmain, paint);
 }
+
+Brush *BKE_paint_toolslots_brush_get(Paint *paint, int slot_index)
+{
+	if (slot_index < paint->tool_slots_len) {
+		PaintToolSlot *tslot = &paint->tool_slots[slot_index];
+		return tslot->brush;
+	}
+	return NULL;
+}
diff --git a/source/blender/makesrna/RNA_enum_types.h b/source/blender/makesrna/RNA_enum_types.h
index 935af5c8bbd..8376bdefbc4 100644
--- a/source/blender/makesrna/RNA_enum_types.h
+++ b/source/blender/makesrna/RNA_enum_types.h
@@ -120,6 +120,7 @@ extern const EnumPropertyItem rna_enum_operator_property_tags[];
 
 extern const EnumPropertyItem rna_enum_brush_sculpt_tool_items[];
 extern const EnumPropertyItem rna_enum_brush_vertex_tool_items[];
+extern const EnumPropertyItem rna_enum_brush_gpencil_types_items[];
 extern const EnumPropertyItem rna_enum_brush_image_tool_items[];
 
 extern const EnumPropertyItem rna_enum_particle_edit_hair_brush_items[];
diff --git a/source/blender/makesrna/intern/rna_brush.c b/source/blender/makesrna/intern/rna_brush.c
index 0bcb29fe860..ac41666a79f 100644
--- a/source/blender/makesrna/intern/rna_brush.c
+++ b/source/blender/makesrna/intern/rna_brush.c
@@ -124,14 +124,14 @@ const EnumPropertyItem rna_enum_brush_image_tool_items[] = {
 	{0, NULL, 0, NULL, NULL}
 };
 
-#ifndef RNA_RUNTIME
-static EnumPropertyItem rna_enum_gpencil_brush_types_items[] = {
+const EnumPropertyItem rna_enum_brush_gpencil_types_items[] = {
 	{GPAINT_TOOL_DRAW, "DRAW", ICON_GP_STROKE, "Draw", "The brush is of type used for drawing strokes"},
 	{GPAINT_TOOL_FILL, "FILL", ICON_COLOR, "Fill", "The brush is of type used for filling areas"},
 	{GPAINT_TOOL_ERASE, "ERASE", ICON_PANEL_CLOSE, "Erase", "The brush is used for erasing strokes"},
 	{0, NULL, 0, NULL, NULL}
 };
 
+#ifndef RNA_RUNTIME
 static EnumPropertyItem rna_enum_gpencil_brush_eraser_modes_items[] = {
 	{ GP_BRUSH_ERASER_SOFT, "SOFT", 0, "Soft", "Use soft eraser" },
 	{ GP_BRUSH_ERASER_HARD, "HARD", 0, "Hard", "Use hard eraser" },
@@ -1360,7 +1360,7 @@ static void rna_def_brush(BlenderRNA *brna)
 
 	prop = RNA_def_property(srna, "gpencil_tool", PROP_ENUM, PROP_NONE);
 	RNA_def_property_enum_sdna(prop, NULL, "gpencil_tool");
-	RNA_def_property_enum_items(prop, rna_enum_gpencil_brush_types_items);
+	RNA_def_property_enum_items(prop, rna_enum_brush_gpencil_types_items);
 	RNA_def_property_ui_text(prop, "Type", "Category of the brush");
 	RNA_def_parameter_clear_flags(prop, PROP_ANIMATABLE, 0);
 
diff --git a/source/blender/makesrna/intern/rna_workspace_api.c b/source/blender/makesrna/intern/rna_workspace_api.c
index 83ee5195fd8..4cb74ac1479 100644
--- a/source/blender/makesrna/intern/rna_workspace_api.c
+++ b/source/blender/makesrna/intern/rna_workspace_api.c
@@ -116,13 +116,20 @@ static void rna_WorkspaceTool_refresh_from_context(
 				}
 			}
 			else {
-				Paint *paint = BKE_paint_get_active(scene, view_layer);
-				if (paint) {
+				const ePaintMode paint_mode = BKE_paintmode_get_from_tool(tref);
+				Paint *paint = BKE_paint_get_active_from_paintmode(scene, paint_mode);
+				const EnumPropertyItem *items = BKE_paint_get_tool_enum_from_paintmode(paint_mode);
+				if (paint && paint->brush && items) {
 					const ID *brush = (ID *)paint->brush;
-					if (brush) {
-						if (!STREQ(tref_rt->data_block, brush->name + 2)) {
-							STRNCPY(tref_rt->data_block, brush->name + 2);
-							STRNCPY(tref->idname, brush->name + 2);
+					const char tool_type = *(char *)POINTER_OFFSET(brush, paint->runtime.tool_offset);
+					const int i = RNA_enum_from_value(items, tool_type);
+					/* Possible when loading files from the future. */
+					if (i != -1) {
+						const char *name = items[i].name;
+						const char *identifier = items[i].identifier;
+						if (!STREQ(tref_rt->data_block, identifier)) {
+							STRNCPY(tref_rt->data_block, identifier);
+							STRNCPY(tref->idname, name);
 						}
 					}
 				}
diff --git a/source/blender/windowmanager/intern/wm_toolsystem.c b/source/blender/windowmanager/intern/wm_toolsystem.c
index 565fade50bb..04a3da5f01f 100644
--- a/source/blender/windowmanager/intern/wm_toolsystem.c
+++ b/source/blender/windowmanager/intern/wm_toolsystem.c
@@ -41,6 +41,7 @@
 #include "DNA_workspace_types.h"
 #include "DNA_object_types.h"
 
+#include "BKE_brush.h"
 #include "BKE_context.h"
 #include "BKE_library.h"
 #include "BKE_main.h"
@@ -242,19 +243,28 @@ static void toolsystem_ref_link(bContext *C, WorkSpace *workspace, bToolRef *tre
 			}
 		}
 		else {
-			struct Brush *brush = (struct Brush *)BKE_libblock_find_name(bmain, ID_BR, tref_rt->data_block);
-			if (brush) {
+			const ePaintMode paint_mode = BKE_paintmode_get_from_tool(tref);
+			BLI_assert(paint_mode != ePaintInvalid);
+			const EnumPropertyItem *items = BKE_paint_get_tool_enum_from_paintmode(paint_mode);
+			BLI_assert(items != NULL);
+
+			const int i = items ? RNA_enum_from_identifier(items, tref_rt->data_block) : -1;
+			if (i != -1) {
+				const int slot_index = items[i].value;
 				wmWindowManager *wm = bmain->wm.first;
 				for (wmWindow *win = wm->windows.first; win; win = win->next) {
 					if (workspace == WM_window_get_active_workspace(win)) {
 						Scene *scene = WM_window_get_active_scene(win);
-						ViewLayer *view_layer = WM_window_get_active_view_layer(win);
-						Paint *paint = BKE_paint_get_active(scene, view_layer);
-						if (paint) {
-							if (brush) {
-								BKE_paint_brush_set(paint, brush);
-							}
+						Paint *paint = BKE_paint_get_active_from_paintmode(scene, paint_mode);
+						struct Brush *brush = BKE_paint_toolslots_brush_get(paint, slot_index);
+						if (brush == NULL) {
+							/* Could make into a function. */
+							brush = BKE_brush_add(bmain, items[i].name, paint->runtime.ob_mode);
+							char *tool_type = (char *)POINTER_OFFSET(brush, paint->runtime.tool_offset);
+							*tool_type = slot_index;
+							BKE_paint_brush_set(paint, brush);
 						}
+						BKE_paint_brush_set(paint, brush);
 					}
 				}
 			}