k3d/share/shaders/k3d_skin1.sl:22: * blemishfreq, blemishthresh,blemhishopac = control the freqency, threshold and opacity
k3d/share/shaders/k3d_skin1.sl:176:  float blemishfreq  = 12,
k3d/share/shaders/k3d_skin1.sl:238:  PP = transform ("shader",P) * blemishfreq;
