How does ray tracing work?

26 Haz 21:43

Why do we even need ray tracing in production, bro? I'm genuinely curious. These guys are chasing after fine calculations, but if you just want 60 FPS in a game, you'd go straight for rasterization. The toughest part about ray tracing is making it work in real-time, and even that's only possible now thanks to next-gen GPUs. When I was optimizing the game engine for my first startup, all this theory took me months. Luckily, today we have NVIDIA and AMD GPUs that have optimized this as much as possible. Global illumination is basically just modeling how light bounces around the environment. I think shadow mapping isn't much different from a simple shadows.lua script—its shadow caster-free version just compares depths from the light source to calculate shadows. As for ambient occlusion, it measures how much nearby objects block light, so it's basically asking, "How dark is this point?" You can see the difference here: shadow mapping calculates shadows, while ambient occlusion gives a softer dark effect. So when optimizing, you really need to think about which one you actually need. My advice? Before you start coding, sketch out a scenario on paper. Separate the paths of light coming directly from the source and those reflected like mirrors, so you can optimize each function. We used this method in optimizing the renderer for my second startup, and it gave us a huge performance boost. At the end of the day, everything comes down to light, but as I said, we now have the tools. Maybe you could even build your own simple ray tracer using the Vulkan API—it'd be a cool project to pass the time.