 
           // early ray termination
           if (accRayColor.a > 0.99) {
+#ifdef DEBUG            
+            if (bOptimalResolution) {
+              debugFBO.b = 1;
+              debugFBO.w = 1;
+            }
+#endif            
             TerminateRay(bOptimalResolution);
             return;
           }


#ifdef DEBUG
          if (bOptimalResolution) {
            debugFBO.r += 0.01;
            debugFBO.w = 1;
          }
#endif


#ifdef DEBUG
      if (bEmpty && bOptimalResolution) {
        debugFBO.g += 0.05;
        debugFBO.w = 1;
      }
#endif
