Originally Posted by 8051
What exactly does global illumination do? It just looks to me like the entire scene has been brightened?
It applies lighting to ALL normals based on their normal, thus makes a texture bias as already partially illuminated and does so in such a way that "blooms" to objects near each other.
Its like full ray tracing but manufactured in china as a spray on product and doesn't need vector resolution steps, basically an assumed light on everything so you don't have to do calculations for more than highlights. How it works along side RTX is that the RTX then doesn't need to actually apply ray-tracing on a pixel level for indirect illumination, just calculate a much rougher gradient to apply to the global illumination value in that area of items. It is a beautiful hack of processing power. There's a bit more to it that I'm far too tired to grammar right now but it isn't actually lighting, just illumination.