k3d/share/shaders/k3d_stones.sl:26: * stonecolor, groundcolor = this is obvious, isn't it?
k3d/share/shaders/k3d_stones.sl:92:   color  groundcolor = color (.45,0.35,0.2);
k3d/share/shaders/k3d_stones.sl:109: surface_color = groundcolor;
