Changes to Brush texture workflow

This changes how textures are accessed from Brushes, with the intention of simplifying 
the workflow, and reducing the amount of clicking. Rather than the previous texture slots 
(which didn't work as a stack anyway), brushes now have a single texture linked. Rather 
than taking time having to set up your slots in advance, you can now select and change 
textures directly as you sculpt/paint on the fly. For complex brushes, node textures can 
be used, or for fast access, it's easy to make a duplicate of your brush with the texture 
you like and assign a hotkey.

Brush textures can now be chosen from a new Textures panel in the brush tool 
properties - click on the thumbnail to open a texture selector. This is done using a new 
variation on the ID template - the number of rows and columns to display in the popup 
can be customised in the UI scripts.

1 files changed, 14 insertions, 44 deletions

diff --git a/source/blender/blenkernel/intern/brush.c b/source/blender/blenkernel/intern/brush.c
index 667b0d50ee9..444c6d2c903 100644
--- a/source/blender/blenkernel/intern/brush.c
+++ b/source/blender/blenkernel/intern/brush.c
@@ -100,19 +100,11 @@ Brush *add_brush(const char *name)
 Brush *copy_brush(Brush *brush)
 {
 	Brush *brushn;
-	MTex *mtex;
-	int a;
 	
 	brushn= copy_libblock(brush);
 
-	for(a=0; a<MAX_MTEX; a++) {
-		mtex= brush->mtex[a];
-		if(mtex) {
-			brushn->mtex[a]= MEM_dupallocN(mtex);
-			if(mtex->tex) id_us_plus((ID*)mtex->tex);
-		}
-	}
-
+	if(brush->mtex.tex) id_us_plus((ID*)brush->mtex.tex);
+	
 	brushn->curve= curvemapping_copy(brush->curve);
 
 	/* enable fake user by default */
@@ -127,17 +119,8 @@ Brush *copy_brush(Brush *brush)
 /* not brush itself */
 void free_brush(Brush *brush)
 {
-	MTex *mtex;
-	int a;
-
-	for(a=0; a<MAX_MTEX; a++) {
-		mtex= brush->mtex[a];
-		if(mtex) {
-			if(mtex->tex) mtex->tex->id.us--;
-			MEM_freeN(mtex);
-		}
-	}
-
+	if(brush->mtex.tex) brush->mtex.tex->id.us--;
+	
 	curvemapping_free(brush->curve);
 }
 
@@ -295,8 +278,8 @@ void brush_curve_preset(Brush *b, BrushCurvePreset preset)
 
 static MTex *brush_active_texture(Brush *brush)
 {
-	if(brush && brush->texact >= 0)
-		return brush->mtex[brush->texact];
+	if(brush)
+		return &brush->mtex;
 	return NULL;
 }
 
@@ -304,8 +287,7 @@ int brush_texture_set_nr(Brush *brush, int nr)
 {
 	ID *idtest, *id=NULL;
 
-	if(brush->mtex[brush->texact])
-		id= (ID *)brush->mtex[brush->texact]->tex;
+	id= (ID *)brush->mtex.tex;
 
 	idtest= (ID*)BLI_findlink(&G.main->tex, nr-1);
 	if(idtest==0) { /* new tex */
@@ -316,13 +298,7 @@ int brush_texture_set_nr(Brush *brush, int nr)
 	if(idtest!=id) {
 		brush_texture_delete(brush);
 
-		if(brush->mtex[brush->texact]==NULL) {
-			brush->mtex[brush->texact]= add_mtex();
-			brush->mtex[brush->texact]->r = 1.0f;
-			brush->mtex[brush->texact]->g = 1.0f;
-			brush->mtex[brush->texact]->b = 1.0f;
-		}
-		brush->mtex[brush->texact]->tex= (Tex*)idtest;
+		brush->mtex.tex= (Tex*)idtest;
 		id_us_plus(idtest);
 
 		return 1;
@@ -333,16 +309,10 @@ int brush_texture_set_nr(Brush *brush, int nr)
 
 int brush_texture_delete(Brush *brush)
 {
-	if(brush->mtex[brush->texact]) {
-		if(brush->mtex[brush->texact]->tex)
-			brush->mtex[brush->texact]->tex->id.us--;
-		MEM_freeN(brush->mtex[brush->texact]);
-		brush->mtex[brush->texact]= NULL;
-
-		return 1;
-	}
+	if(brush->mtex.tex)
+		brush->mtex.tex->id.us--;
 
-	return 0;
+	return 1;
 }
 
 int brush_clone_image_set_nr(Brush *brush, int nr)
@@ -383,7 +353,7 @@ void brush_check_exists(Brush **brush, const char *name)
 /* Brush Sampling */
 void brush_sample_tex(Brush *brush, float *xy, float *rgba)
 {
-	MTex *mtex= brush->mtex[brush->texact];
+	MTex *mtex= &brush->mtex;
 
 	if (mtex && mtex->tex) {
 		float co[3], tin, tr, tg, tb, ta;
@@ -741,7 +711,7 @@ static void brush_painter_refresh_cache(BrushPainter *painter, float *pos)
 {
 	Brush *brush= painter->brush;
 	BrushPainterCache *cache= &painter->cache;
-	MTex *mtex= brush->mtex[brush->texact];
+	MTex *mtex= &brush->mtex;
 	int size;
 	short flt;
 
@@ -976,7 +946,7 @@ float brush_curve_strength(Brush *br, float p, const float len)
 unsigned int *brush_gen_texture_cache(Brush *br, int half_side)
 {
 	unsigned int *texcache = NULL;
-	MTex *mtex = br->mtex[br->texact];
+	MTex *mtex = &br->mtex;
 	TexResult texres;
 	int hasrgb, ix, iy;
 	int side = half_side * 2;