k3d/share/shaders/k3d_lensflare.sl:22: *   rainbowintensity - intensity of rainbow effect (0=none)
k3d/share/shaders/k3d_lensflare.sl:23: *   rainbowradius, rainbowwidth - size of the rainbow
k3d/share/shaders/k3d_lensflare.sl:70:rainbow(float x, dx)
k3d/share/shaders/k3d_lensflare.sl:94:		      float rainbowintensity = 0.03;
k3d/share/shaders/k3d_lensflare.sl:95:		      float rainbowradius = 0.5; float rainbowwidth = 0.2;
k3d/share/shaders/k3d_lensflare.sl:167:    if(rainbowintensity > 0)
k3d/share/shaders/k3d_lensflare.sl:170:	  brightness * (rainbowintensity / intensity) *
k3d/share/shaders/k3d_lensflare.sl:171:	  rainbow((dist / rainbowradius - 1) / rainbowwidth,
k3d/share/shaders/k3d_lensflare.sl:172:		  (dPndc / rainbowradius) / rainbowwidth);
