Texture painting:

Do not generate materials/images/UVs if they are missing.

Now we spawn a panel ("Missing Data") with operators to generate the missing data and
pop a warning if user tries to paint without them.

The reason we have reverted this is that it is too easy to end up with more textures
than we wanted. It was impossible to enter texture paint without having textures added,
and code makes too many assumptions about what user may want.

Discussed during Sunday's meeting.

This might be a candidate for 2.72a but I'm not sure how other artists will take this
(and how refined and crash-free it is), better make a few iterations first.

And for interested parties...test please, don't wait until after a release to poke with such issues.

Also, add slot operator now adds a new unconnected image node in cycles. Only
used in the "Missing Data" panel. This should be a separate commit but I am squashing it into the same commit because
it relies too much on changes done here and can be reverted easily if complainstorm occurs again.

1 files changed, 29 insertions, 19 deletions

diff --git a/source/blender/editors/sculpt_paint/paint_image.c b/source/blender/editors/sculpt_paint/paint_image.c
index 87866f764bc..f4189b512e5 100644
--- a/source/blender/editors/sculpt_paint/paint_image.c
+++ b/source/blender/editors/sculpt_paint/paint_image.c
@@ -57,6 +57,7 @@
 
 #include "BKE_context.h"
 #include "BKE_depsgraph.h"
+#include "BKE_DerivedMesh.h"
 #include "BKE_brush.h"
 #include "BKE_image.h"
 #include "BKE_main.h"
@@ -87,6 +88,7 @@
 #include "RNA_enum_types.h"
 
 #include "GPU_draw.h"
+#include "GPU_buffers.h"
 
 #include "BIF_gl.h"
 #include "BIF_glutil.h"
@@ -752,14 +754,16 @@ static PaintOperation *texture_paint_init(bContext *C, wmOperator *op, const flo
 	copy_v2_v2(pop->prevmouse, mouse);
 	copy_v2_v2(pop->startmouse, mouse);
 
-	if ((brush->imagepaint_tool == PAINT_TOOL_FILL) && (brush->flag & BRUSH_USE_GRADIENT)) {
-		pop->cursor = WM_paint_cursor_activate(CTX_wm_manager(C), image_paint_poll, gradient_draw_line, pop);
-	}
-
 	/* initialize from context */
 	if (CTX_wm_region_view3d(C)) {
 		Object *ob = OBACT;
-		paint_proj_mesh_data_ensure(C, ob, op);
+		bool uvs, mat, tex, stencil;
+		if (!BKE_paint_proj_mesh_data_check(scene, ob, &uvs, &mat, &tex, &stencil)) {
+			BKE_paint_data_warning(op->reports, uvs, mat, tex, stencil);
+			MEM_freeN(pop);
+			WM_event_add_notifier(C, NC_SCENE | ND_TOOLSETTINGS, NULL);
+			return NULL;			
+		}
 		pop->mode = PAINT_MODE_3D_PROJECT;
 		pop->custom_paint = paint_proj_new_stroke(C, ob, mouse, mode);
 	}
@@ -773,6 +777,10 @@ static PaintOperation *texture_paint_init(bContext *C, wmOperator *op, const flo
 		return NULL;
 	}
 
+	if ((brush->imagepaint_tool == PAINT_TOOL_FILL) && (brush->flag & BRUSH_USE_GRADIENT)) {
+		pop->cursor = WM_paint_cursor_activate(CTX_wm_manager(C), image_paint_poll, gradient_draw_line, pop);
+	}
+	
 	settings->imapaint.flag |= IMAGEPAINT_DRAWING;
 	ED_undo_paint_push_begin(UNDO_PAINT_IMAGE, op->type->name,
 	                         ED_image_undo_restore, ED_image_undo_free, NULL);
@@ -1381,29 +1389,31 @@ static int texture_paint_toggle_exec(bContext *C, wmOperator *op)
 		 * cache in case we are loading a file */
 		BKE_texpaint_slots_refresh_object(scene, ob);
 
-		paint_proj_mesh_data_ensure(C, ob, op);
-
+		BKE_paint_proj_mesh_data_check(scene, ob, NULL, NULL, NULL, NULL);
+		
 		/* entering paint mode also sets image to editors */
 		if (imapaint->mode == IMAGEPAINT_MODE_MATERIAL) {
 			Material *ma = give_current_material(ob, ob->actcol); /* set the current material active paint slot on image editor */
 
-			if (ma->texpaintslot)
+			if (ma && ma->texpaintslot)
 				ima = ma->texpaintslot[ma->paint_active_slot].ima;
 		}
 		else if (imapaint->mode == IMAGEPAINT_MODE_MATERIAL) {
 			ima = imapaint->canvas;
 		}	
 		
-		for (sc = bmain->screen.first; sc; sc = sc->id.next) {
-			ScrArea *sa;
-			for (sa = sc->areabase.first; sa; sa = sa->next) {
-				SpaceLink *sl;
-				for (sl = sa->spacedata.first; sl; sl = sl->next) {
-					if (sl->spacetype == SPACE_IMAGE) {
-						SpaceImage *sima = (SpaceImage *)sl;
-						
-						if (!sima->pin)
-							ED_space_image_set(sima, scene, scene->obedit, ima);
+		if (ima) {
+			for (sc = bmain->screen.first; sc; sc = sc->id.next) {
+				ScrArea *sa;
+				for (sa = sc->areabase.first; sa; sa = sa->next) {
+					SpaceLink *sl;
+					for (sl = sa->spacedata.first; sl; sl = sl->next) {
+						if (sl->spacetype == SPACE_IMAGE) {
+							SpaceImage *sima = (SpaceImage *)sl;
+							
+							if (!sima->pin)
+								ED_space_image_set(sima, scene, scene->obedit, ima);
+						}
 					}
 				}
 			}
@@ -1420,7 +1430,7 @@ static int texture_paint_toggle_exec(bContext *C, wmOperator *op)
 		toggle_paint_cursor(C, 1);
 	}
 
-	DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
+	GPU_drawobject_free(ob->derivedFinal);
 	WM_event_add_notifier(C, NC_SCENE | ND_MODE, scene);
 
 	return OPERATOR_FINISHED;