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Comment by nu11ptr | Hacker News Reader

From the PR, it sounds like the switch to WGPU is only for linux. The team was reluctant to do the same for macOS/Windows since they felt their native renderer on those platforms was better and less memory intensive.

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> they felt their native renderer on those platforms was better and less memory intensive

This definitely would be worth some profiling. I don't think it's a given that their custom stacks are going to beat wgpu in a meaningful way.

WebGPU has some surprising performance problems (although I only checked Google's Dawn library, not Rust's wgpu), and the amount of code that's pulled into the project is massive. A well-made Metal renderer which only implements the needed features will easily be 100x smaller (in terms of linecount) and most likely faster.

There is also the issue that it is designed with JavaScript and browser sandbox in mind, thus the wrong abstraction level for native graphics middleware.

I am still curious how much uptake WebGPU will end up having on Android, or if Java/Kotlin folks will keep targeting OpenGL ES.

Please elaborate, I am curious to why would you think WebGPU would meaningfully beat their Metal/DirectX renderers.

I don't think it would, but I don't think it's a given that their homegrown renderer is wildly more performant either - people tend to overestimate the performance of naive renderers

wgpu isn't a renderer though, it's an abstraction layer. It's honestly hard for me to imagine it ever being faster than writing directx or metal directly. It has many advantages, like that it runs in browsers and is memory safe (and in the case of dawn, has great error messages). But it's hard for it to ever be as fast as the native APIs it calls for you.

I think most non-trivial cross-platform graphics applications eventually end up with some kind of hardware abstraction layer. The interesting part is comparing how wgpu performs vs. something custom developed for that application, especially if their renderer is mostly GPU-bound anyway. wgpu definitely has some level of overhead, but so do all of the other custom abstraction layers out there.

WGPU is just a layer over the top of the native APIs on any given platform so unless Zed's DirectX/Metal renderers were particularly bad it's unlikely WGPU will be better here.

I'm not saying it would be better, I'm saying it may not be particularly much worse. Which still might make it worth simplifying everything by settling on one rendering abstraction

> This definitely would be worth some profiling. I don't think it's a given that their custom stacks are going to beat wgpu in a meaningful way.

They probably will for memory usage. Current wgpu seems to have a floor around ~100mb that isn't there with other rendering backends (and it was more like ~60mb with wgpu a few months / versions ago).

Not sure if this is fixable in wgpu, or do with spec compatibility (my guess would be that it's fixable, just not top priority for the team atm).

Yes, but they can add a flag to switch renderers on startup like they had for blade.

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