You're really good at math, and thanks again It wasn't straightforward to come up with pattern that cover all polygon sizes, including triangles.

The function works fine with triangles still, and it's now in use in the editor too. I hope the (0, 1, 2) vertices weren't necessary somehow for your projection formula, would guess no. Regards to projection, what did it actually do? It transforms vertices to plane of face normal's space? (that sounded weird) It's cool idea, and i noticed immediately how few calculations it's doing. Definitely much much faster than if dealing with normal way like 3D ray-triangle. Kind of genious.