@dialNforNinja said:
Would it help at all to look at how Blender's vector blur node works? Obviously not a copy and paste job, but math is math, no matter the language. Probably too slow for real time rendering, I suppose.
Modern motion blur techniques usually require motion vectors, which Godot does not have. Motion vectors are far from trivial to integrate to an existing rendering engine, especially when you take all edge cases into account (transparent materials, skinned meshes, soft bodies, custom shaders, …).