[buff-a]

>Ray tracing involves projecting light from the "eye" towards the scene, whereas in real life the light is being projected from the scene towards the eye.

I can't write a decent reply to this without having terrifying flashbacks of late night cramming for third year physics exams. But basically, raytracing's idea that "if it didn't hit your eye, who cares" is somewhat backed up by theory =)

[toemetoch]

You mean the law of reversibility?

[buff-a]

I was thinking more along the lines that without the eye, the idea of light being projected in any direction at all has no meaning =) And then we could get started on the concepts of time and ordering.

But since I'm no longer a third year physicist contemplating the nature of existence, I just simulate light statistically. And sometimes that means doing things like "Photon Mapping", which is precisely raytracing, but the kind of raytracing you get when you know how to optimize an algorithm implemented as a computer program.

http://en.wikipedia.org/wiki/Double-slit_experiment#Delayed_...

http://en.wikipedia.org/wiki/Interpretations_of_quantum_mech...

[its_so_on]

http://www.meritnation.com/discuss/question/32137

principle of reversibility of light: "The principle that if a beam of light is reflected back on itself, it will traverse the same path or paths as it did before reversal. The principle of reversibility states that light will follow exactly the same path if its direction of travel is reversed."