4 ms·

If a post processing filter takes 18ms to complete, uncontested, you can't "pipeline the shit" out of it. You can get a frame at least every 18ms. Adding more l

If a post processing filter takes 18ms to complete, uncontested, you can't "pipeline the shit" out of it. You can get a frame at least every 18ms. Adding more load won't magically transform throughput into latency, it will just make your throughput worse.

vlovich123 6y ago
Right. If it's 18ms before you get any result you can't do anything & that's the lower bound on the FPS you can display. The problem is with respect to the pipeline granularity you're thinking about. I'm not suggesting creating a deeper pipeline. I'm saying make the granularity smaller. Can the app simulate the portion of the world that's actually needed for display? Can the rendering engine get you the result for the first 1/4 of a frame in 1/4 of the time it would take to do the whole screen? Can the display pipeline understand portions of the same frame being submitted at different times? Ultimately can you drive different parts of the display at different refresh rates based on when those pieces arrive. I'm not trying to make this seem like a trivial thing. The single global view is easy to reason about. We need fundamental research into this space on how to build physics & rendering engines that can unlock this kind of granularity. There's massive data dependencies that are really challenging to untangle. Each layer in the pipe, from physics engines & rendering engines, to display pipeline APIs, to GPUs likes to treat everything else like an opaque system with each providing a complete result to the next. There's an enormous amount of existing architecture that would have to be rewritten. I'm also 100% clear that it's entirely possible that parts of the pipeline can't be segmented in this way to get good looking result or it might make the SW burden on content creators to costly. I still believe it's the right direction though & is the only way you're going to ever see 8k displays @ 120hz or above. Well, that's not strictly true. The other trick will be to use motion estimation & neural nets to provide the interpolation when you drive it higher than the content can support - you can see that with all the motion estimation & supersampling improvements that various vendors are producing.

vlovich123 6y ago

Right. If it's 18ms before you get any result you can't do anything & that's the lower bound on the FPS you can display. The problem is with respect to the pipeline granularity you're thinking about. I'm not suggesting creating a deeper pipeline. I'm saying make the granularity smaller. Can the app simulate the portion of the world that's actually needed for display? Can the rendering engine get you the result for the first 1/4 of a frame in 1/4 of the time it would take to do the whole screen? Can the display pipeline understand portions of the same frame being submitted at different times? Ultimately can you drive different parts of the display at different refresh rates based on when those pieces arrive. I'm not trying to make this seem like a trivial thing. The single global view is easy to reason about. We need fundamental research into this space on how to build physics & rendering engines that can unlock this kind of granularity. There's massive data dependencies that are really challenging to untangle. Each layer in the pipe, from physics engines & rendering engines, to display pipeline APIs, to GPUs likes to treat everything else like an opaque system with each providing a complete result to the next. There's an enormous amount of existing architecture that would have to be rewritten. I'm also 100% clear that it's entirely possible that parts of the pipeline can't be segmented in this way to get good looking result or it might make the SW burden on content creators to costly. I still believe it's the right direction though & is the only way you're going to ever see 8k displays @ 120hz or above. Well, that's not strictly true. The other trick will be to use motion estimation & neural nets to provide the interpolation when you drive it higher than the content can support - you can see that with all the motion estimation & supersampling improvements that various vendors are producing.