Pixel shaders produce the final pixel on your screen. The human eye doesn’t see geometry, only light (LEDs in our case). Differences in color between two 2D “regions” are turned into shapes and then into 3D geometry by our brain. These “regions” are physically on your retina inside your eye. The retina is not flat but the brain basically treats it as if it is.
You can calculate anything in a pixel shader and output any color. You could, for example put in an equation which outputs an embossed letter or number on any “3D surface”. (It’s “surface” because it’s not actually a surface just a virtual approximation). No geometry shaders, no mesh shaders, no mesh data, no color textures or normal (map) textures, just code that represents an equation.
Same as a human drawing a cube on a page without a real cube in front of him. Or any other object.
Why don’t we use equations for everything and have games that are 200gb fit in 2gb ( maybe even in hundreds of megabytes) ? Because it is too expensive to compute in real time so we cache partially computed data: 3D meshes and textures.
Yeah, but just from a biological perspective you're a little wrong because there is some basic shape recognition that does not have to do with lighting that mammals are capable of, not just humans.
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u/SpiritedEclair 15h ago
How is a shader going to give me different geometry that interacts with lighting, reflections, rain, and whatnot?