k3d/share/shaders/k3d_square_ridges.sl:26:#define MIN_FILTER_WIDTH 1.0e-6
k3d/share/shaders/k3d_square_ridges.sl:27:#define filter_width(x) max(abs(Du(x)*du) + abs(Dv(x)*dv), MIN_FILTER_WIDTH)
k3d/share/shaders/k3d_warningstripes.sl:26:#define MIN_FILTER_WIDTH 1.0e-6
k3d/share/shaders/k3d_warningstripes.sl:27:#define filter_width(x) max(abs(Du(x)*du) + abs(Dv(x)*dv), MIN_FILTER_WIDTH)
