wgpu: WIP precompiled shaders #6501
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Introduce a `build_shaders` feature in Ruffle's `wgpu` backend and enable it on desktop. When enabled, the WGSL shaders are precompiled using `naga` in a build script to the SPIR-V format. Then, those SPIR-V modules are used directly instead of the WGSL sources. This approach has 2 major advantages: 1. It should reduce Ruffle's executable size by a decent amount of KBs (I expect 100KB-200KB), because the binary SPIR-V modules are much smaller than the WGSL textual source code, plus hopefully the Rust compiler will be smart enough to eliminate `naga`'s WGSL parsing code, which is pretty high on the `cargo bloat` list. 2. It should improve the startup time, as less logic is involved when loading precompiled SPIR-V modules.
Wait... isn't this PR basically an opposite of e10d0fc ? Requiring |
This PR adds |
no, there's a the It's okay on desktop (hopefully it passes through the spir-v module as-is?), but on web we definitely don't want to drag extra wgpu features along. |
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Closing for now as the WGSL frontend code still appears in the binary. I've opened gfx-rs/wgpu#2549 to see if disabling WGSL using a Cargo feature could be possible. |
Introduce a
build_shadersfeature in Ruffle'swgpubackend andenable it on desktop. When enabled, the WGSL shaders are precompiled
using
nagain a build script to the SPIR-V format. Then, thoseSPIR-V modules are used directly instead of the WGSL sources.
This approach has 2 major advantages:
(I expect 100KB-200KB), because the binary SPIR-V modules are much smaller
than the WGSL textual source code, plus hopefully the Rust compiler
will be smart enough to eliminate
naga's WGSL parsing code, whichis pretty high on the
cargo bloatlist.loading precompiled SPIR-V modules.
However, I'm almost sure this feature won't work for WebGPU as it only supports WGSL. But maybe we can still minify the WGSL source code to reduce the WebAssembly binary size.