Fix #31093: Brush's "Paint curve presets" in Image paint in UV\Image Editor doesn't work if weight paint mode is active

Some operators like curve presets, color sample and some more were using object's
mode to distinguish in which mode user is currently painting. Such approach fails
in cases when there's paint mode active in 3D viewport and Image Editor.

Changed logic here to use some context's state like active space which helps
distinguishing current paint mode more accurate.

Ported all areas which uses paint_get_active() to new paint_get_active_from_context().
There're still some calls to paint_get_active(), but that shouldn't be harmful due
to that places indeed have object's mode as priority when getting paint mode.

source/blender/blenkernel/BKE_paint.h

@@ -32,6 +32,7 @@
  *  \ingroup bke
  */
 
+struct bContext;
 struct Brush;
 struct MDisps;
 struct MeshElemMap;
@@ -55,6 +56,7 @@ void free_paint(struct Paint *p);
 void copy_paint(struct Paint *src, struct Paint *tar);
 
 struct Paint *paint_get_active(struct Scene *sce);
+struct Paint *paint_get_active_from_context(const struct bContext *C);
 struct Brush *paint_brush(struct Paint *paint);
 void paint_brush_set(struct Paint *paint, struct Brush *br);
 

source/blender/blenkernel/intern/paint.c

@@ -41,6 +41,7 @@
 #include "BLI_utildefines.h"
 
 #include "BKE_brush.h"
+#include "BKE_context.h"
 #include "BKE_library.h"
 #include "BKE_paint.h"
 #include "BKE_subsurf.h"
@@ -83,6 +84,53 @@ Paint *paint_get_active(Scene *sce)
 	return NULL;
 }
 
+Paint *paint_get_active_from_context(const bContext *C)
+{
+	Scene *sce = CTX_data_scene(C);
+
+	if (sce) {
+		ToolSettings *ts = sce->toolsettings;
+		Object *obact = NULL;
+
+		if (sce->basact && sce->basact->object)
+			obact = sce->basact->object;
+
+		if (CTX_wm_space_image(C) != NULL) {
+			if (obact->mode == OB_MODE_EDIT) {
+				if (ts->use_uv_sculpt)
+					return &ts->uvsculpt->paint;
+				else
+					return &ts->imapaint.paint;
+			}
+			else {
+				return &ts->imapaint.paint;
+			}
+		}
+		else {
+			switch (obact->mode) {
+				case OB_MODE_SCULPT:
+					return &ts->sculpt->paint;
+				case OB_MODE_VERTEX_PAINT:
+					return &ts->vpaint->paint;
+				case OB_MODE_WEIGHT_PAINT:
+					return &ts->wpaint->paint;
+				case OB_MODE_TEXTURE_PAINT:
+					return &ts->imapaint.paint;
+				case OB_MODE_EDIT:
+					if (ts->use_uv_sculpt)
+						return &ts->uvsculpt->paint;
+					else
+						return &ts->imapaint.paint;
+			}
+
+			/* default to image paint */
+			return &ts->imapaint.paint;
+		}
+	}
+
+	return NULL;
+}
+
 Brush *paint_brush(Paint *p)
 {
 	return p ? p->brush : NULL;

source/blender/editors/sculpt_paint/paint_cursor.c

@@ -333,7 +333,7 @@ static int sculpt_get_brush_geometry(bContext *C, ViewContext *vc,
                                      float location[3])
 {
 	Scene *scene = CTX_data_scene(C);
-	Paint *paint = paint_get_active(scene);
+	Paint *paint = paint_get_active_from_context(C);
 	Brush *brush = paint_brush(paint);
 	float window[2];
 	int hit;
@@ -503,7 +503,7 @@ static void paint_cursor_on_hit(Sculpt *sd, Brush *brush, ViewContext *vc,
 static void paint_draw_cursor(bContext *C, int x, int y, void *UNUSED(unused))
 {
 	Scene *scene = CTX_data_scene(C);
-	Paint *paint = paint_get_active(scene);
+	Paint *paint = paint_get_active_from_context(C);
 	Brush *brush = paint_brush(paint);
 	ViewContext vc;
 	float final_radius;
@@ -605,7 +605,7 @@ static void paint_draw_cursor(bContext *C, int x, int y, void *UNUSED(unused))
 
 void paint_cursor_start(bContext *C, int (*poll)(bContext *C))
 {
-	Paint *p = paint_get_active(CTX_data_scene(C));
+	Paint *p = paint_get_active_from_context(C);
 
 	if (p && !p->paint_cursor)
 		p->paint_cursor = WM_paint_cursor_activate(CTX_wm_manager(C), poll, paint_draw_cursor, NULL);

source/blender/editors/sculpt_paint/paint_image.c

@@ -5215,7 +5215,7 @@ static void brush_drawcursor(bContext *C, int x, int y, void *UNUSED(customdata)
 
 	Scene *scene = CTX_data_scene(C);
 	//Brush *brush= image_paint_brush(C);
-	Paint *paint = paint_get_active(scene);
+	Paint *paint = paint_get_active_from_context(C);
 	Brush *brush = paint_brush(paint);
 
 	if (paint && brush && paint->flags & PAINT_SHOW_BRUSH) {
@@ -5420,13 +5420,12 @@ void PAINT_OT_grab_clone(wmOperatorType *ot)
 
 static int sample_color_exec(bContext *C, wmOperator *op)
 {
-	Scene *scene = CTX_data_scene(C);
 	Brush *brush = image_paint_brush(C);
 	ARegion *ar = CTX_wm_region(C);
 	int location[2];
 
 	RNA_int_get_array(op->ptr, "location", location);
-	paint_sample_color(scene, ar, location[0], location[1]);
+	paint_sample_color(C, ar, location[0], location[1]);
 
 	WM_event_add_notifier(C, NC_BRUSH | NA_EDITED, brush);
 	

source/blender/editors/sculpt_paint/paint_intern.h

@@ -137,7 +137,7 @@ float paint_get_tex_pixel(struct Brush *br, float u, float v);
 int imapaint_pick_face(struct ViewContext *vc, const int mval[2], unsigned int *index, unsigned int totface);
 void imapaint_pick_uv(struct Scene *scene, struct Object *ob, unsigned int faceindex, const int xy[2], float uv[2]);
 
-void paint_sample_color(struct Scene *scene, struct ARegion *ar, int x, int y);
+void paint_sample_color(const struct bContext *C, struct ARegion *ar, int x, int y);
 void BRUSH_OT_curve_preset(struct wmOperatorType *ot);
 
 void PAINT_OT_face_select_linked(struct wmOperatorType *ot);

source/blender/editors/sculpt_paint/paint_ops.c

@@ -60,7 +60,7 @@
 static int brush_add_exec(bContext *C, wmOperator *UNUSED(op))
 {
 	/*int type = RNA_enum_get(op->ptr, "type");*/
-	Paint *paint = paint_get_active(CTX_data_scene(C));
+	Paint *paint = paint_get_active_from_context(C);
 	struct Brush *br = paint_brush(paint);
 
 	if (br)
@@ -68,7 +68,7 @@ static int brush_add_exec(bContext *C, wmOperator *UNUSED(op))
 	else
 		br = BKE_brush_add("Brush");
 
-	paint_brush_set(paint_get_active(CTX_data_scene(C)), br);
+	paint_brush_set(paint, br);
 
 	return OPERATOR_FINISHED;
 }
@@ -91,7 +91,7 @@ static void BRUSH_OT_add(wmOperatorType *ot)
 static int brush_scale_size_exec(bContext *C, wmOperator *op)
 {
 	Scene *scene = CTX_data_scene(C);
-	Paint  *paint =  paint_get_active(scene);
+	Paint  *paint =  paint_get_active_from_context(C);
 	struct Brush  *brush =  paint_brush(paint);
 	// Object *ob=     CTX_data_active_object(C);
 	float scalar = RNA_float_get(op->ptr, "scalar");
@@ -173,7 +173,7 @@ static void PAINT_OT_vertex_color_set(wmOperatorType *ot)
 
 static int brush_reset_exec(bContext *C, wmOperator *UNUSED(op))
 {
-	Paint *paint = paint_get_active(CTX_data_scene(C));
+	Paint *paint = paint_get_active_from_context(C);
 	struct Brush *brush = paint_brush(paint);
 	Object *ob = CTX_data_active_object(C);
 

source/blender/editors/sculpt_paint/paint_stroke.c

@@ -100,10 +100,11 @@ typedef struct PaintStroke {
 /*** Cursor ***/
 static void paint_draw_smooth_stroke(bContext *C, int x, int y, void *customdata) 
 {
-	Brush *brush = paint_brush(paint_get_active(CTX_data_scene(C)));
+	Paint *paint = paint_get_active_from_context(C);
+	Brush *brush = paint_brush(paint);
 	PaintStroke *stroke = customdata;
 
-	glColor4ubv(paint_get_active(CTX_data_scene(C))->paint_cursor_col);
+	glColor4ubv(paint->paint_cursor_col);
 	glEnable(GL_LINE_SMOOTH);
 	glEnable(GL_BLEND);
 
@@ -141,7 +142,7 @@ static float event_tablet_data(wmEvent *event, int *pen_flip)
 static void paint_brush_stroke_add_step(bContext *C, wmOperator *op, wmEvent *event, float mouse_in[2])
 {
 	Scene *scene = CTX_data_scene(C);
-	Paint *paint = paint_get_active(scene);
+	Paint *paint = paint_get_active_from_context(C);
 	Brush *brush = paint_brush(paint);
 	PaintStroke *stroke = op->customdata;
 	float mouse[3];
@@ -281,7 +282,7 @@ PaintStroke *paint_stroke_new(bContext *C,
 {
 	PaintStroke *stroke = MEM_callocN(sizeof(PaintStroke), "PaintStroke");
 
-	stroke->brush = paint_brush(paint_get_active(CTX_data_scene(C)));
+	stroke->brush = paint_brush(paint_get_active_from_context(C));
 	view3d_set_viewcontext(C, &stroke->vc);
 	view3d_get_transformation(stroke->vc.ar, stroke->vc.rv3d, stroke->vc.obact, &stroke->mats);
 
@@ -394,7 +395,7 @@ static void paint_stroke_sample_average(const PaintStroke *stroke,
 
 int paint_stroke_modal(bContext *C, wmOperator *op, wmEvent *event)
 {
-	Paint *p = paint_get_active(CTX_data_scene(C));
+	Paint *p = paint_get_active_from_context(C);
 	PaintStroke *stroke = op->customdata;
 	PaintSample sample_average;
 	float mouse[2];
@@ -518,7 +519,7 @@ void paint_stroke_set_mode_data(PaintStroke *stroke, void *mode_data)
 
 int paint_poll(bContext *C)
 {
-	Paint *p = paint_get_active(CTX_data_scene(C));
+	Paint *p = paint_get_active_from_context(C);
 	Object *ob = CTX_data_active_object(C);
 
 	return p && ob && paint_brush(p) &&

source/blender/editors/sculpt_paint/paint_utils.c

@@ -333,9 +333,9 @@ int imapaint_pick_face(ViewContext *vc, const int mval[2], unsigned int *index,
 }
 
 /* used for both 3d view and image window */
-void paint_sample_color(Scene *scene, ARegion *ar, int x, int y)    /* frontbuf */
+void paint_sample_color(const bContext *C, ARegion *ar, int x, int y)    /* frontbuf */
 {
-	Brush *br = paint_brush(paint_get_active(scene));
+	Brush *br = paint_brush(paint_get_active_from_context(C));
 	unsigned int col;
 	char *cp;
 
@@ -357,7 +357,7 @@ void paint_sample_color(Scene *scene, ARegion *ar, int x, int y)    /* frontbuf
 
 static int brush_curve_preset_exec(bContext *C, wmOperator *op)
 {
-	Brush *br = paint_brush(paint_get_active(CTX_data_scene(C)));
+	Brush *br = paint_brush(paint_get_active_from_context(C));
 	BKE_brush_curve_preset(br, RNA_enum_get(op->ptr, "shape"));
 
 	return OPERATOR_FINISHED;
@@ -365,7 +365,7 @@ static int brush_curve_preset_exec(bContext *C, wmOperator *op)
 
 static int brush_curve_preset_poll(bContext *C)
 {
-	Brush *br = paint_brush(paint_get_active(CTX_data_scene(C)));
+	Brush *br = paint_brush(paint_get_active_from_context(C));
 
 	return br && br->curve;
 }

source/blender/editors/space_buttons/buttons_texture.c

@@ -175,7 +175,7 @@ static void buttons_texture_users_from_context(ListBase *users, const bContext *
 	if (!(pinid || pinid == &scene->id)) {
 		ob = (scene->basact) ? scene->basact->object : NULL;
 		wrld = scene->world;
-		brush = paint_brush(paint_get_active(scene));
+		brush = paint_brush(paint_get_active_from_context(C));
 	}
 
 	if (ob && ob->type == OB_LAMP && !la)

source/blender/editors/space_view3d/view3d_edit.c

@@ -498,7 +498,7 @@ static void viewops_data_create(bContext *C, wmOperator *op, wmEvent *event)
 static void viewops_data_free(bContext *C, wmOperator *op)
 {
 	ARegion *ar;
-	Paint *p = paint_get_active(CTX_data_scene(C));
+	Paint *p = paint_get_active_from_context(C);
 
 	if (op->customdata) {
 		ViewOpsData *vod = op->customdata;