Inverse raytracing

Hello

maybe a bit of an odd question, it’s relating to a theoretical physics-related research project.

Would it be possible to reverse/invert the raytracing in a render? I.e. such that lights would be consuming photons and that they would bounce off objects in the reverse direction. (I’m not completely sure about the detailed situation that would imply myself, feel free to elaborate if you can imagine it)

Either through the settings or through a possible plug-in? Who could I turn to for that?

Many thanks
Sascha

Well… What would you need that for? :slight_smile:
If you want your “lights” to consume photons, just turn them pure black! And then there’s questions like where would the photons then come from if they can’t come from the lights? Basically a ray of light doesn’t give damn whether it’s traced from the camera to the light, or from light to the camera…

negative light is simple substracting instead adding light
you can test it with render every lamp separate and then mix it in nodes

or

blender support also negative RGB values for (emission) color
and negative energy values

but do not do this…