Pass:polygon

[bjornbytes]

Should we have Pass:polygon? It's a more convenient way to draw triangles, non-plane quadrilaterals, or maybe the faces of the new convex hull physics shape.

The input points would be directly rendered as a triangle fan, and so the points need to be coplanar and the resulting polygon would need to be simple (i.e. not self-intersecting) and convex. LÖVR could try to do validation or just render it anyway (I lean towards no validation).

The normal vector of the polygon could be computed as the cross product of the 2 direction vectors formed by the first 3 points. I don't think we can compute UVs.