Originally Posted by lifejunkie
What exactly are you trying yo do?
Might be a more efficient way.
Short version: using polygons as light sources. Rather than rendering the entire scene again for each pixel like radiosity does, I was thinking we can just collide any likely faces with the lightsource to calculate how much of it is visible, then multiply by the normal factors (direction, distance, brightness, etc).
In this case we can consider 3-4 faces against one, which is vastly faster than repeatedly drawing the scene or doing a raytrace. Similarly, in theory with a faster system it could allow for realtime global illumination.
In 2D it's trivially easy/fast:
because we can just do a little bit of trig to calculate how much of the face is visible. In 3D it's a completely different story, as far as I can tell.
You'd have to project the faces into 2D, then work out how much of which is visible to get your brightness percentage.