Window Culling

https://devforum.roblox.com/t/window-culling-a-utility-for-portal-based-visibility/4666858/1 Standard frustum culling checks if something is on screen. This doesn’t. This utility answers a different question: can this object be seen through this specific window? Not “is it in the camera’s view?” - “is it geometrically possible to see it through that rectangular hole in the wall?” I have a moving train with windows. I wanted to skip updating objects that the player has no line of sight to through any window. But the same utility applies to any portal, doorframe, gap, or opening - if you can model it as a rectangle, you can cull against it.