- OSX bugfix: drawing selection code for vpaint and faceselect happens in AUX

buffers now. It only works nice at OSX (tested, linux and windows do not
  support it nicely)
  This fixes the annoying flashing during paint or select

source/blender/src/editface.c

@@ -445,8 +445,13 @@ TFace* face_pick(Mesh *me, short x, short y)
 		backdrawview3d(0);
 	}
 	/* Read the pixel under the cursor */
+#ifdef __APPLE__
+	glReadBuffer(GL_AUX0);
+#endif
 	glReadPixels(x+curarea->winrct.xmin, y+curarea->winrct.ymin, 1, 1,
 		GL_RGBA, GL_UNSIGNED_BYTE, &col);
+	glReadBuffer(GL_BACK);
+
 	/* Unbelievable! */
 	if (G.order==B_ENDIAN) {
 		SWITCH_INT(col);
@@ -532,9 +537,12 @@ void face_borderselect()
 	
 	val= get_border(&rect, 3);
 	
-	/* why readbuffer here? shouldn't be necessary */
-	glReadBuffer(GL_BACK);	
-
+	/* why readbuffer here? shouldn't be necessary (maybe a flush or so) */
+	glReadBuffer(GL_BACK);
+#ifdef __APPLE__
+	glReadBuffer(GL_AUX0); /* apple only */
+#endif
+	
 	if(val) {
 		selar= MEM_callocN(me->totface+1, "selar");
 		
@@ -571,6 +579,9 @@ void face_borderselect()
 		allqueue(REDRAWVIEW3D, 0);
 		allqueue(REDRAWIMAGE, 0);
 	}
+#ifdef __APPLE__	
+	glReadBuffer(GL_BACK);
+#endif
 }
 
 #define TEST_STRUBI 1