Update?

[phildlight]

I would love it if there was an update render method. Some way for the program to check to see what changed from the previous render and only re-render what's changed. Sort of a cache of values that is checked against the current process. I have no idea how or if this is possible, but it would seem that if it processed the scene once, then stored those values, and simply adjusted the render to reflect the changes?

[travistlo]

The problem with that is the bouncing of light. You change one thing, and light bounces differently.