A graphics programmer writes about GPU rendering, shaders, and real-time graphics techniques, including how engines like Unreal render a frame.
Commenters recommend it as a collection of graphics learning material and link its Unreal frame-rendering breakdown as interesting reading.
> Are you arguing for a better software abstraction, a different hardware abstraction or both?
I don't speak for Raph, but imo it seems like he was arguing for both, and I agree with him.
On the hardware side, GPUs have struggled with dynamic workloads at the API level (not e.g. thread-level dynamism, that's a separate topic) for around a decade. Indirect commands gave you some of that so at least the size of your data/workload can be variable if not the workloads themselves, then mesh shaders gave you a little more access to geometry processing, and finally workgraphs and device generated commands lets you have an actually dynamically defined workload (e.g. completely skipping dispatches for shading materials that weren't used on screen this frame). However it's still very early days, and the performance issues and lack of easy portability are problematic. See https://interplayoflight.wordpress.com/2024/09/09/an-introduction-to-workgraphs-part-2-performance for instance.
On the software side shading languages have been garbage for far longer than hardware has been a problem. It's only in the last year or two that a proper language server for writing shaders has even existed (Slang's LSP). Much less the innumerable driver compiler bugs, lack of well defined semantics and memory model until the last few years, or the fact that we're still manually dividing work into the correct cache-aware chunks.
Here's an article[0] by Kostas Anagnostou that I found helpful. He's spent over 2 decades in the graphics industry.
His article gives a path for learning from the top of the stack and going down to the lower level stuff afterwards.
TL;DR is Shadertoy -> Unity/Unreal -> Direct3D/OpenGL
[0] https://interplayoflight.wordpress.com/2018/07/08/how-to-start-learn-graphics-programming/
it would be cool to see a more comprehensive comparison including methods with raytracing
they have MLAB in their performance comparison table, is that ray traced? from this blog i think it sounds like it there's a rasterized version and a way to use ray tracing https://interplayoflight.wordpress.com/2023/07/30/raytraced-order-independent-transparency-part-2/
Marmoset's articles are a great intro. Probably the most accessible I've found.
If anyone wants to read a lot more, here's a collection of possibly a majority of the non-academic material to be found online: https://interplayoflight.wordpress.com/2013/12/30/readings-on-physically-based-rendering/
How Unreal renders a frame is also interesting:
https://interplayoflight.wordpress.com/2017/10/25/how-unreal-renders-a-frame/