--- rxvt-unicode/src/rxvtimg.C	2012/06/08 10:28:30	1.61
+++ rxvt-unicode/src/rxvtimg.C	2012/06/08 21:48:07	1.66
@@ -211,7 +211,6 @@
   if (ref->cnt == 1 && ref->ours)
     return;
 
-  //TODO: maybe should reify instead
   Pixmap pm2 = XCreatePixmap (s->display->dpy, s->display->root, ref->w, ref->h, format->depth);
   GC gc = XCreateGC (s->display->dpy, pm, 0, 0);
   XCopyArea (s->display->dpy, pm, pm2, gc, 0, 0, ref->w, ref->h, 0, 0);
@@ -333,7 +332,7 @@
 }
 
 void
-rxvt_img::brightness (unsigned short r, unsigned short g, unsigned short b, unsigned short a)
+rxvt_img::brightness (uint16_t r, uint16_t g, uint16_t b, uint16_t a)
 {
   Display *dpy = s->display->dpy;
   Picture src = create_xrender_mask (dpy, pm, True);
@@ -353,10 +352,13 @@
 }
 
 void
-rxvt_img::contrast (unsigned short r, unsigned short g, unsigned short b, unsigned short a)
+rxvt_img::contrast (uint16_t r, uint16_t g, uint16_t b, uint16_t a)
 {
   if (!(s->display->flags & DISPLAY_HAS_RENDER_MUL))
-    return;
+    {
+      rxvt_warn ("rxvt_img::contrast operation not supported on this display, RENDER extension too old.\n");
+      return;
+    }
 
   Display *dpy = s->display->dpy;
   Picture src = create_xrender_mask (dpy, pm, True);
@@ -409,9 +411,10 @@
 
   Display *dpy = s->display->dpy;
 
-  bool alpha = !format->direct.alphaMask
-               && (x || y)
-               && repeat == RepeatNone;
+  // add an alpha channel if...
+  bool alpha = !format->direct.alphaMask // pixmap has none yet
+               && (x || y)               // we need one because of non-zero offset
+               && repeat == RepeatNone;  // and we have no good pixels to fill with
 
   rxvt_img *img = new rxvt_img (s, alpha ? find_alpha_format_for (dpy, format) : format, 0, 0, w, h, repeat);
   img->alloc ();
@@ -471,10 +474,8 @@
     for (int j = 0; j < 3; ++j)
       xfrm.matrix [i][j] = XDoubleToFixed (matrix [i * 3 + j]);
 
-#if 0
   xfrm.matrix [0][2] -= XDoubleToFixed (x);//TODO
   xfrm.matrix [1][2] -= XDoubleToFixed (y);
-#endif
 
   XRenderSetPictureFilter (dpy, src, "good", 0, 0);
   XRenderSetPictureTransform (dpy, src, &xfrm);