Thanks for the replies everyone, I think I get it now
In: 24
It’s a technique used to generate the way light works in an image.
Imagine a computer drawing a bubble with a horse behind it. In the dumbest sense possible you’d see a horse with a white bubble in front of it, but that’s not how physics actually works. In real physics light from the sun will hit the horse, reflect, then travel through the bubble and get distorted like a lens and then come to you, the viewer.
Having a computer just make a white bubble in front of a horse is easy, but having a computer calculate the path of light from the sun, to the horse, distorted through the bubble, then to your eye is complicated and takes time and computer power.
So going back maybe 15 years ago, a video game which is being constantly “Drawn” by the system would be lazy and just make a white bubble in front of the horse. A Blockbuster Hollywood movie might get a supercomputer to do the fancy light-path version, but that would take hours and $$$$ to render.
In modern computers, they have gotten so powerful that they can do this real-life looking light-path tracing in real time, making video game graphics potentially look photo-realistic. This process is “ray tracing” (following light rays)
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