Fix for new UI system and vertexpaint/faceselect/weightpaint/texturepaint

If backbuffer is in use for selection codes, the system switches back to
frontbuffer drawing temporally. Is easier solution now.

Next commit; fix for new 'zbuffer clipped selection', which also doesnt
work after using a pulldown or popup menu.

5 files changed, 46 insertions, 21 deletions

diff --git a/source/blender/include/BIF_interface.h b/source/blender/include/BIF_interface.h
index 9f8afd76ea6..01fc74430e1 100644
--- a/source/blender/include/BIF_interface.h
+++ b/source/blender/include/BIF_interface.h
@@ -75,6 +75,7 @@ struct ScrArea;
 #define UI_BLOCK_NUMSELECT	16
 #define UI_BLOCK_ENTER_OK	32
 #define UI_BLOCK_NOSHADOW	64
+#define UI_BLOCK_FRONTBUFFER	128
 
 	/* block->flag bits 12-15 are identical to but->flag bits */
 
diff --git a/source/blender/include/interface.h b/source/blender/include/interface.h
index 281e2e4be10..baa5e0d7418 100644
--- a/source/blender/include/interface.h
+++ b/source/blender/include/interface.h
@@ -41,8 +41,6 @@
 #define UI_MAX_NAME_STR	64
 #define UI_ARRAY	29
 
-
-
 /* uiBut->flag */
 #define UI_SELECT		1
 #define UI_MOUSE_OVER	2
@@ -51,10 +49,6 @@
 /* warn: rest of uiBut->flag in BIF_interface.c */
 
 
-/* block->frontbuf: (only internal here). this signals something was drawn, for flush */
-#define UI_HAS_DRAWN 	1
-
-
 /* internal panel drawing defines */
 #define PNL_GRID	4
 #define PNL_DIST	8
@@ -186,7 +180,8 @@ struct uiBlock {
 	int afterval, flag;
 	void *curfont;
 	
-	short autofill, win, winq, direction, dt, frontbuf, auto_open, pad;  //frontbuf see below
+	short autofill, win, winq, direction, dt;
+	short needflush, auto_open, in_use, pad;  //flush see below
 	void *overdraw;
 	
 	float xofs, yofs;  	// offset to parent button
diff --git a/source/blender/src/drawview.c b/source/blender/src/drawview.c
index 47d158476dd..1c1e83932a1 100644
--- a/source/blender/src/drawview.c
+++ b/source/blender/src/drawview.c
@@ -1476,7 +1476,10 @@ static void view3d_panel_object(short cntrl)	// VIEW3D_HANDLER_OBJECT
 
 	if(uiNewPanel(curarea, block, "Transform Properties", "View3d", 10, 230, 318, 204)==0) return;
 	
-	if((G.f & (G_VERTEXPAINT|G_TEXTUREPAINT))==0) {
+	if(G.f & (G_VERTEXPAINT|G_FACESELECT|G_TEXTUREPAINT|G_WEIGHTPAINT)) {
+		uiBlockSetFlag(block, UI_BLOCK_FRONTBUFFER);	// force old style frontbuffer draw
+	}
+	else {
 		uiDefBut(block, TEX, B_IDNAME, "OB: ",	10,180,140,20, ob->id.name+2, 0.0, 19.0, 0, 0, "");
 		uiDefIDPoinBut(block, test_obpoin_but, B_OBJECTPANELPARENT, "Par:", 160, 180, 140, 20, &ob->parent, "Parent Object"); 
 	}
@@ -1532,6 +1535,10 @@ static void view3d_panel_background(short cntrl)	// VIEW3D_HANDLER_BACKGROUND
 	uiSetPanelHandler(VIEW3D_HANDLER_BACKGROUND);  // for close and esc
 	if(uiNewPanel(curarea, block, "Background Image", "View3d", 340, 10, 318, 204)==0) return;
 
+	if(G.f & (G_VERTEXPAINT|G_FACESELECT|G_TEXTUREPAINT|G_WEIGHTPAINT)) {
+		uiBlockSetFlag(block, UI_BLOCK_FRONTBUFFER);	// force old style frontbuffer draw
+	}
+	
 	if(vd->flag & V3D_DISPBGPIC) {
 		if(vd->bgpic==0) {
 			vd->bgpic= MEM_callocN(sizeof(BGpic), "bgpic");
@@ -1623,6 +1630,10 @@ static void view3d_panel_properties(short cntrl)	// VIEW3D_HANDLER_SETTINGS
 	uiSetPanelHandler(VIEW3D_HANDLER_PROPERTIES);  // for close and esc
 	if(uiNewPanel(curarea, block, "View Properties", "View3d", 340, 10, 318, 204)==0) return;
 
+	if(G.f & (G_VERTEXPAINT|G_FACESELECT|G_TEXTUREPAINT|G_WEIGHTPAINT)) {
+		uiBlockSetFlag(block, UI_BLOCK_FRONTBUFFER);	// force old style frontbuffer draw
+	}
+
 	uiDefBut(block, LABEL, 1, "Grid:",					10, 180, 150, 19, NULL, 0.0, 0.0, 0, 0, "");
 	uiDefButF(block, NUM, REDRAWVIEW3D, "Spacing:",		10, 160, 140, 19, &vd->grid, 0.001, 100.0, 10, 0, "Set the distance between grid lines");
 	uiDefButS(block, NUM, REDRAWVIEW3D, "Lines:",		10, 136, 140, 19, &vd->gridlines, 0.0, 100.0, 100, 0, "Set the number of grid lines");
diff --git a/source/blender/src/interface.c b/source/blender/src/interface.c
index f96ccd6f6cd..91d4334a81d 100644
--- a/source/blender/src/interface.c
+++ b/source/blender/src/interface.c
@@ -316,8 +316,16 @@ void ui_block_flush_back(uiBlock *block)
 	int minx, miny, sizex, sizey;
 	
 	/* note; this routine also has to work for block loop */
-	if(block->frontbuf==0) return;
+	if(block->needflush==0) return;
 
+	/* exception, when we cannot use backbuffer for draw... */
+	if(block->flag & UI_BLOCK_FRONTBUFFER) {
+		glFlush();
+		glDrawBuffer(GL_BACK);
+		block->needflush= 0;
+		return;
+	}
+	
 	/* copy pixels works on window coords, so we move to window space */
 
 	ui_graphics_to_window(block->win, &block->flush.xmin, &block->flush.ymin);
@@ -346,7 +354,7 @@ void ui_block_flush_back(uiBlock *block)
 		markdirty_win_back(block->win);
 	}
 	
-	block->frontbuf= 0; 
+	block->needflush= 0; 
 }
 
 /* merge info for live updates in frontbuf */
@@ -354,13 +362,17 @@ void ui_block_set_flush(uiBlock *block, uiBut *but)
 {
 	/* clear signal */
 	if(but==NULL) {
-		block->frontbuf= 0; 
+		block->needflush= 0; 
 
 		block->flush.xmin= 0.0;
 		block->flush.xmax= 0.0;
 	}
 	else {
-		if(block->frontbuf==0) {
+		/* exception, when we cannot use backbuffer for draw... */
+		if(block->flag & UI_BLOCK_FRONTBUFFER) {
+			glDrawBuffer(GL_FRONT);
+		}
+		else if(block->needflush==0) {
 			/* first rect */
 			block->flush.xmin= but->x1;
 			block->flush.xmax= but->x2;
@@ -374,7 +386,8 @@ void ui_block_set_flush(uiBlock *block, uiBut *but)
 			if(block->flush.ymin > but->y1) block->flush.ymin= but->y1;
 			if(block->flush.ymax < but->y2) block->flush.ymax= but->y2;
 		}
-		block->frontbuf= UI_HAS_DRAWN;
+		
+		block->needflush= 1;
 		
 	}
 }
@@ -3421,20 +3434,23 @@ int uiDoBlocks(ListBase *lb, int event)
 				if( block->flag & UI_BLOCK_LOOP) {
 					block->overdraw= ui_begin_overdraw((int)block->minx-1, (int)block->miny-6, (int)block->maxx+6, (int)block->maxy+1);
 				}
+				block->in_use= 1;	// is always a menu
 				uiDrawBlock(block);
 				block->flag &= ~UI_BLOCK_REDRAW;
 			}
-
+			
+			block->in_use= 1; // bit awkward, but now we can detect if frontbuf flush should be set
 			retval= ui_do_block(block, &uevent);
+			block->in_use= 0;
 			if(retval==UI_EXIT_LOOP) break;
 			
 			/* now a new block could be created for menus, this is 
 			   inserted in the beginning of a list */
 			
 			/* is there a flush cached? */
-			if(block->frontbuf == UI_HAS_DRAWN) {
+			if(block->needflush) {
 				ui_flush_overdraw(block->overdraw);
-				block->frontbuf= 0;
+				block->needflush= 0;
 			}
 			
 			/* to make sure the matrix of the panel works for menus too */
@@ -3460,17 +3476,19 @@ int uiDoBlocks(ListBase *lb, int event)
 				uiDrawBlock(block);
 				block->flag &= ~UI_BLOCK_REDRAW;
 				ui_flush_overdraw(block->overdraw);
-				block->frontbuf= 0;
+				block->needflush= 0;
 			}
 			
 			uevent.event= extern_qread(&uevent.val);
 			
 			if(uevent.event) {
+				block->in_use= 1; // bit awkward, but now we can detect if frontbuf flush should be set
 				retval= ui_do_block(block, &uevent);
+				block->in_use= 0;
 			
-				if(block->frontbuf == UI_HAS_DRAWN) { // flush now, maybe new menu was opened
+				if(block->needflush) { // flush now, maybe new menu was opened
 					ui_flush_overdraw(block->overdraw);
-					block->frontbuf= 0;
+					block->needflush= 0;
 				}
 
 				if(retval & UI_RETURN) {
diff --git a/source/blender/src/interface_draw.c b/source/blender/src/interface_draw.c
index ea16229074c..3ef7d802730 100644
--- a/source/blender/src/interface_draw.c
+++ b/source/blender/src/interface_draw.c
@@ -1715,10 +1715,10 @@ void ui_draw_but(uiBut *but)
 	double value;
 	float x1, x2, y1, y2, fac;
 	
-	if(but==0) return;
+	if(but==NULL) return;
 
 	/* signal for flush buttons and menus */
-	ui_block_set_flush(but->block, but);
+	if(but->block->in_use) ui_block_set_flush(but->block, but);
 		
 	switch (but->type) {