--- rxvt-unicode/src/rxvttoolkit.C	2012/02/24 07:10:54	1.131
+++ rxvt-unicode/src/rxvttoolkit.C	2012/06/03 15:50:22	1.132
@@ -468,6 +468,28 @@
   XUnloadFont (dpy, f);
 #endif
 
+  flags = 0;
+#if XRENDER
+  int major, minor;
+  if (XRenderQueryVersion (dpy, &major, &minor))
+    {
+      flags |= DISPLAY_HAS_RENDER;
+
+      if (major > 0 || (major == 0 && minor >= 11))
+        flags |= DISPLAY_HAS_RENDER_MUL;
+
+      XFilters *filters = XRenderQueryFilters (dpy, root);
+      if (filters)
+        {
+          for (int i = 0; i < filters->nfilter; i++)
+            if (!strcmp (filters->filter[i], FilterConvolution))
+              flags |= DISPLAY_HAS_RENDER_CONV;
+
+          XFree (filters);
+        }
+    }
+#endif
+
   int fd = XConnectionNumber (dpy);
 
   // try to detect whether we have a local connection.