k3d/share/shaders/k3d_volcube.sl:15:   RunShadowPass       - set to 1 if running a shadow pass.
k3d/share/shaders/k3d_volcube.sl:197:	     float  RunShadowPass  = 0;
k3d/share/shaders/k3d_volcube.sl:240:	if(cur_density > 0 && RunShadowPass == 0){
