k3d/share/shaders/k3d_castucco.sl:13: *   trough, peak - define the shape of the valleys and mesas of the stucco.
k3d/share/shaders/k3d_castucco.sl:26:			  float trough = -0.15, peak = 0.35
k3d/share/shaders/k3d_castucco.sl:41:  disp = Km * smoothstep(trough, peak, disp);
