WGPU Slang Renderer

A good chunk of this repo has been made following this tutorial: https://sotrh.github.io/learn-wgpu

Prerequisites

Required

• The build script needs the shader-slang tools installed and added to PATH in order to compile the slang shaders in the shaders/ directory.

Optional

• If you want to run the scripts to convert textures/materials into ktx2, you will need the ktx-tools and the OpenImageIO tools installed and added to your PATH.

Building the project

For WASM

Run the following command to build the wasm library:

cd ./crates/renderer
wasm-pack build --target web

Dev Workflow

For WASM

While developing for web, you need to set up two directory symlinks:

1. One for your dir containing the built and packaged WASM library.
2. One for your dir containing the static files that WASM will fetch at runtime

For example, when serving our project with Svelte, here's how those symlinks should be:

1. <RUST_PROJECT_ROOT>/crates/renderer/pkg -> <SVELTE_PROJECT_ROOT>/src/lib/pkg

For Svelte, /src/lib/ is where libraries directly references in components should go.

2. <RUST_PROJECT_ROOT>/crates/renderer/res -> <SVELTE_PROJECT_ROOT>/static/<PATH_TO_PAGE>/res

For example, if we want to serve our project at http://localhost/my_page, then we need to use the path /static/my_page/res under our Svelte project.

Once the symlinks are set up, you can import and init the WASM library:

import init from '$lib/pkg/renderer.js';

onMount(async () => {
      init().catch((error) => {
            if (!error.message.startsWith("Using exceptions for control flow,")) {
                  throw error;
            }
      });
});

TODO

• Use slangc to compile modules into slang-IR files before compiling entry points to improve compile times.
• Handle case where slangc can't be found in the build script. Should it fail to build, or just continue with a warning?
• Check if output on WebGL is always sRGB, even if screen is Display P3
• Address dots in the pre-filtering by sampling mips during the pre-filtering stage. (This will need to happen in a shader)
• Store SH coefficients as a key/value pair in the .ktx2 file, instead of a separate .bin file.
• Create PR for Python example instead of C example in OCIO docs for shaders
• Use block compression on all ktx2 textures
• impl of AsBindGroup in Material has too many empty functions. Maybe some of those methods in AsBindGroup should be moved to another derived trait that is only for UniformBuffer bindgroups?
• Refactor to have a LightManager and do an instance draw call from there to draw all light debug meshes.