ref: 212ca282c42e99e03121727c138a34584777ee60
parent: 1a839bc268588144d9b39c45a665545c1aaa2ef3
author: rodri <rgl@antares-labs.eu>
date: Sat Nov 11 07:41:54 EST 2023
add support for OBJ models (triangles only). also put a guard on the filltriangle slopes to avoid division by zero.