k3d/share/shaders/k3d_lensflare.sl:20: *   starburstradius, starburstnpoints, starburstfalloff - control the
k3d/share/shaders/k3d_lensflare.sl:91:		      float starburstradius = 0.5;
k3d/share/shaders/k3d_lensflare.sl:158:	  sqrt(brightness) * 5 * mix(.2, starburstradius, urand());
