k3d/share/shaders/k3d_crayon.sl:73:	float trs = spline(1 - density, 0 , -0.195997, -0.128361, -0.0738346,	-0.0316483,
k3d/share/shaders/k3d_crayon.sl:87:	m = smoothstep(trs - .1, trs + .3, lmks);	
