catchyid Posted August 25, 2016 Share Posted August 25, 2016 Hi, I have a question regarding Ray/Attribute interpolate SOPs. Ray SOP This SOP stores the hit position in two point attributes: "primitive number", and "primitive uvw". So far so good! Attribute Interpolate SOP Somehow this function is doing interpolation (see attached), but I don't understand how it works! To be more specific: -I understand interpolation as: v_interpolated = t v_a + (1-t) v_b -Ray SOP creates two point attributes: prim # , prim uv -Attribute Interpolate uses ONLY the two attributes created by Ray SOP to compute new point positions! i.e. it computes new point positions based on prim # and uv. The problem with that is that original point position values not used which is the essence of any interpolation I know my question is not very clear or maybe I just need more coffee to get things straight Anyways, your feedback will be always appreciated.... Quote Link to comment Share on other sites More sharing options...
catchyid Posted August 25, 2016 Author Share Posted August 25, 2016 Okay, here is a better way to rephrase the question The way Attribute Interpolate node works (at least in my example above) is NOT related to interpolation! Instead, it's basically constructing points in space using coordinate frames (primitive id) and displacements ( uv values)! i.e. , it's like defining a point using a coordinate system and x,y,z values, so where is the interpolation in that? where are values that get mapped to new values? Maybe I miss something here but I feel happy now Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.