diff --git a/src/fl_draw_image_mac.cxx b/src/fl_draw_image_mac.cxx
index d45b1c431..41333e4d8 100644
--- a/src/fl_draw_image_mac.cxx
+++ b/src/fl_draw_image_mac.cxx
@@ -53,8 +53,12 @@ static void innards(const uchar *buf, int X, int Y, int W, int H,
 {
   if (!linedelta) linedelta = W*abs(delta);
 
-  const void *array = buf;
   uchar *tmpBuf = 0;
+  if (!cb) {
+    if (delta < 0) buf -= (W-1)*(-delta);
+    if (linedelta < 0) buf -= (H-1)*abs(delta)*W;
+  }
+  const void *array = buf;
   if (cb || Fl_Surface_Device::surface() != Fl_Display_Device::display_device()) {
     tmpBuf = new uchar[ H*W*abs(delta) ];
     if (cb) {