k3d/share/shaders/k3d_oak.sl:18: *   ringfreq - mean frequency of ring spacing
k3d/share/shaders/k3d_oak.sl:56:		float ringfreq = 8, ringunevenness = 0.5;
k3d/share/shaders/k3d_oak.sl:73:    oaktexture(Pshad, dPshad, ringfreq, ringunevenness, grainfreq, ringnoise,
k3d/share/shaders/k3d_oakplank.sl:25: *   ringfreq - mean frequency of ring spacing
k3d/share/shaders/k3d_oakplank.sl:106:		     float ringfreq = 8, ringunevenness = 0.5;
k3d/share/shaders/k3d_oakplank.sl:141:  float wood = oaktexture(Ppat, dPshad, ringfreq, ringunevenness, grainfreq,
