I am writing a texture splatting pixel shader for meshes (not terrain) whereby I find a UV position from a raycast, which I convert to a local position, and then calculate a bounding box around that position.Then when cycling through the UVs (also converted to local positions) in the shader I am able to check if each UV is within the bounding box, and hence set a colour.The bit I am struggling with is how to map each local position to the bounding box so I can then map that result to the splat texture using UVs or percentages.In the image above I have 6 splat points. As you can see the one is crossing an edge so I need to be able to transform the 3D position along all axes.I was thinking I could flatten/unfold the 3D point, but I'm not sure how to do this with all axes.Any ideas?Thanks!
Unfolding a 3D point to a Cartesian plane
pixel shader