- fix for reported error in drawing 3d window buttons Panel when you have

VertexPaint or FaceSelect mode on.
  The error was caused by not resetting to 2d buttons matrix after drawing
  the color codes for selection in backbuffer.

source/blender/src/drawview.c

@@ -902,6 +902,11 @@ void backdrawview3d(int test)
 #ifdef __APPLE__
 	glDrawBuffer(GL_BACK); /* we were in aux buffers */
 #endif
+
+	/* it is important to end a view in a transform compatible with buttons */
+	persp(PERSP_WIN);  // set ortho
+	bwin_scalematrix(curarea->win, G.vd->blockscale, G.vd->blockscale, G.vd->blockscale);
+
 }