Trouble compiling/rendering on WASM

[PanProsiaczek2137]

I’ve been trying to get renderling working on WASM. I noticed in the repo that there’s mention of building for WASM with the --cfg=web_sys_unstable_apis flag, so I tried that. However, I’m still running into issues.

Here’s the error log from the browser (firefox) console when running trunk serve --open on Windows 10:

surface capabilities: SurfaceCapabilities {
    formats: [
        Bgra8Unorm,
        Rgba8Unorm,
        Rgba16Float,
    ],
    present_modes: [
        Fifo,
    ],
    alpha_modes: [
        Opaque,
    ],
    usages: TextureUsages(
        RENDER_ATTACHMENT,
    ),
} renderling_test-4eab76b1efe735ff.js:1283:17
requested but unsupported features: Features(
    MULTI_DRAW_INDIRECT | VERTEX_WRITABLE_STORAGE | CLEAR_TEXTURE,
) renderling_test-4eab76b1efe735ff.js:1006:17
adapter limits: Limits {
    max_texture_dimension_1d: 16384,
    max_texture_dimension_2d: 16384,
    max_texture_dimension_3d: 2048,
    max_texture_array_layers: 2048,
    max_bind_groups: 8,
    max_bindings_per_bind_group: 65535,
    max_dynamic_uniform_buffers_per_pipeline_layout: 8,
    max_dynamic_storage_buffers_per_pipeline_layout: 4,
    max_sampled_textures_per_shader_stage: 64,
    max_samplers_per_shader_stage: 64,
    max_storage_buffers_per_shader_stage: 64,
    max_storage_textures_per_shader_stage: 64,
    max_uniform_buffers_per_shader_stage: 64,
    max_uniform_buffer_binding_size: 65536,
    max_storage_buffer_binding_size: 1073741824,
    max_vertex_buffers: 16,
    max_buffer_size: 1073741824,
    max_vertex_attributes: 32,
    max_vertex_buffer_array_stride: 2048,
    min_uniform_buffer_offset_alignment: 256,
    min_storage_buffer_offset_alignment: 32,
    max_inter_stage_shader_components: 0,
    max_color_attachments: 8,
    max_color_attachment_bytes_per_sample: 32,
    max_compute_workgroup_storage_size: 32768,
    max_compute_invocations_per_workgroup: 768,
    max_compute_workgroup_size_x: 1024,
    max_compute_workgroup_size_y: 1024,
    max_compute_workgroup_size_z: 64,
    max_compute_workgroups_per_dimension: 65535,
    min_subgroup_size: 0,
    max_subgroup_size: 0,
    max_push_constant_size: 0,
    max_non_sampler_bindings: 1000000,
} renderling_test-4eab76b1efe735ff.js:1283:17
panicked at C:\Users\Mateusz\.cargo\registry\src\index.crates.io-1949cf8c6b5b557f\renderling-0.4.9\src\context.rs:521:14:
called Result::unwrap() on an Err value: CannotRequestDevice { source: RequestDeviceError { inner: WebGpu(JsValue(OperationError: requestDevice: Limit 'maxInterStageShaderComponents' not recognized.
__wbg_get_imports/imports.wbg.__wbg_requestDevice_25da66256442f99f@http://[::1]:8080/renderling_test-4eab76b1efe735ff.js:1885:26
renderling_test.wasm.__wbg_requestDevice_25da66256442f99f externref shim@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[48126]:0xf7068c
renderling_test.wasm.wgpu::backend::webgpu::webgpu_sys::gen_GpuAdapter::GpuAdapter::request_device_with_descriptor::h643ee0738f6e8b18@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[19774]:0xd4274b
renderling_test.wasm.<wgpu::backend::webgpu::ContextWebGpu as wgpu::context::Context>::adapter_request_device::h1db48a247514a0d5@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[4179]:0x882dc0
renderling_test.wasm.<T as wgpu::context::DynContext>::adapter_request_device::h2270f97e24149d7b@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[8942]:0xac34b0
renderling_test.wasm.wgpu::Adapter::request_device::h3ee765ed26586602@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[11147]:0xb7315f
renderling_test.wasm.renderling::context::device::{{closure}}::hfc0f1ac172c9cf78@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[1137]:0x503d8a
renderling_test.wasm.renderling::context::new_windowed_adapter_device_queue::{{closure}}::hcf4dfad621470758@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[684]:0x2ce3db
renderling_test.wasm.renderling::context::Context::try_from_raw_window::{{closure}}::h785d973429419a56@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[1299]:0x56b835
renderling_test.wasm.renderling::context::Context::from_window_async::{{closure}}::h8743534945d4ad39@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[2312]:0x6ebc4e
renderling_test.wasm.renderling_test::State::new::{{closure}}::h004348abf405c9e2@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[639]:0x23c633
renderling_test.wasm.<renderling_test::App as winit::application::ApplicationHandler<renderling_test::CustomUserEvent>>::resumed::{{closure}}::h780bef47cc519817@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[3097]:0x7b007c
renderling_test.wasm.wasm_bindgen_futures::task::singlethread::Task::run::h31cb10f747190220@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[5337]:0x939844
renderling_test.wasm.wasm_bindgen_futures::queue::QueueState::run_all::h8eccdb29bb92fa84@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[4969]:0x904854
renderling_test.wasm.wasm_bindgen_futures::queue::Queue::new::{{closure}}::h4bc43f344b58e6bc@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[25986]:0xe05260
renderling_test.wasm.<dyn core::ops::function::FnMut<(A,)>+Output = R as wasm_bindgen::closure::WasmClosure>::describe::invoke::ha4990cb0d668eb05@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[17987]:0xcf7be0
renderling_test.wasm.closure1889 externref shim@http://[::1]:8080/renderling_test-4eab76b1efe735ff_bg.wasm:wasm-function[48377]:0xf71efc
__wbg_adapter_62@http://[::1]:8080/renderling_test-4eab76b1efe735ff.js:288:10
real@http://[::1]:8080/renderling_test-4eab76b1efe735ff.js:163:20
)) } }

My minimal test project is here

Build command I’m using:
$env:RUSTFLAGS="--cfg=web_sys_unstable_apis" trunk serve --open

Thanks a lot for your time, and also for making this crate! 🙏

[schell]

Thanks for your report! This is my current priority. It's been a bit since I've built for WASM so I expect the repo just needs a bit of tidying to get it compiling again.

[PanProsiaczek2137]

Awesome!
Do you happen to have any rough estimate of how long it might take? I could really use this feature soon… I don’t want to rush you or anything, since you’re doing an amazing job. I’d just like to have an idea of how long I might need to wait.

[schell]

I'm not really sure, but lately I've only been able to work on this project on weekends. I'm in New Zealand so my weekend starts a day earlier than others, so the soonest I could fix this would be within 3 or 4 days.

[schell]

I've reproduced your issue 👍 .

[schell]

Related wgpu / web-sys issue

[schell]

I'm working on a PR #197 that adds WASM test infrastructure to ensure the WASM stuff doesn't lag behind native.

[schell]

@PanProsiaczek2137 would you be able to reference this project via a git dependency? The release on crates.io is a couple versions behind, and I can't publish a new release until Rust-GPU releases spirv-std = 0.10.

I could potentially back-port the wgpu and web-sys updates to the latest renderling tag on crates.io, but the API has change quite a bit since then, for the better.

[schell]

Great, I wish you good luck with project.

Thank you! 🙇

I'd like to help you with some PR, but I don't know enough about wgpu to be useful at the moment, but maybe in the future.

No worries 👍 . I look forward to it, but no pressure :)

I found the cause of the argument of integer logarithm must be positive error. When creating a new stage, if the context's size is UVec2::ZERO, all the downstream textures will be zero as well. The other errors are echoes of the first one, so fixing that issue will fix them all (and then hopefully that's it for errors,lol).

A good fix here would be for renderling to use a proper builder pattern to create the stage, and that could provide sane defaults.
I think that makes the most sense since you might not want your stage to have the same dimensions as the context. I'm not sure what use case having a zero-sized context solves, it sounds a bit like headless rendering, but maybe on WASM the canvas is being resized later, and I think that's a good enough possibility.

[schell]

There's something fishy going on with the window size on WASM. winit doesn't seem to be creating the window with the correct size (800, 600) even with that specifically in the WindowAttributes.

[schell]

Ok, it looks like this is a winit issue, detailed in rust-windowing/winit#2863.

Since that's the case I'm not sure if renderling should worry about supporting zero-sized Contexts. The fix here is probably to defer creating the Context until the window has a size.

[schell]

Here's another PR to fix a couple more things.

[PanProsiaczek2137]

Yay, it's working! 🤩 Thank you very much for your help.