I see that the Colormap VOP is pretty confusing. It has all these plugs for Filter Width, Filter, Mip Levels but has only u and v inputs, not uu and vv for the corners of the sampled quadrilateral. i.e., all these inputs seem to be totally useless since there is no way to perform filtered lookups on any textures (without supplying your own u and v derivatives in the form of quadrilateral).
So, are the docs wrong when they write this?
Houdini Docs colormap(map, u, v, “smode”, “decal”, “tmode”, “repeat”, “border”, {.1,1,1}); colormap(map, u, v, “mode”, “clamp”, “width”, 1.3); colormap(map, u, v, “filter”, “gauss”, “width”, 1.3, “mode”, “repeat”);
…since they have no meaning without derivatives, as in the SOP and COP context. Should they be:
Houdini Docs Wanna Be colormap(map, u-uu/2, v-vv/2, u +uu/2, v+vv/2,…., “smode”, “decal”, “tmode”, “repeat”, “border”, {.1,1,1}); … …
I see that the Colormap VOP is pretty confusing. It has all these plugs for Filter Width, Filter, Mip Levels but has only u and v inputs, not uu and vv for the corners of the sampled quadrilateral. i.e., all these inputs seem to be totally useless since there is no way to perform filtered lookups on any textures (without supplying your own u and v derivatives in the form of quadrilateral).
So, are the docs wrong when they write this?
Houdini Docs colormap(map, u, v, “smode”, “decal”, “tmode”, “repeat”, “border”, {.1,1,1}); colormap(map, u, v, “mode”, “clamp”, “width”, 1.3); colormap(map, u, v, “filter”, “gauss”, “width”, 1.3, “mode”, “repeat”);
…since they have no meaning without derivatives, as in the SOP and COP context. Should they be:
Houdini Docs Wanna Be colormap(map, u-uu/2, v-vv/2, u +uu/2, v+vv/2,…., “smode”, “decal”, “tmode”, “repeat”, “border”, {.1,1,1}); … …
Confused, Jason
You are absolutely correct. The filter, width, extrapolate and interp options are all ignored in the VEX code and shouldn't exist in the VOP since they are misleading.
