WESL Interoperability

We are working with WESL, a community standard for enhanced WGSL, to enable hybrid programs that mix-and-match between shader-centric and host-centric approaches. Shaders written in WGSL or WESL can be reflected into JS/TS as TypeGPU definitions, with proper types generated on the fly.

✨ Take advantage of type-safe buffers while keeping your shaders in WESL
⚔️ Eliminate manual byte alignment and padding

Setting up

This functionality is provided as an extension to wesl-plugin. Consult their documentation on what to install, and how to use it with your bundler of choice.

Our official wesl-ext-typepgu package extends the capabilities of wesl-plugin. Install it before proceeding.

npm add --save-dev wesl-ext-typegpu

pnpm add -D wesl-ext-typegpu

yarn add -D wesl-ext-typegpu

Next up, reference the extension in your bundler’s configuration. Below is an example using Vite.

import { defineConfig } from "vite";
import weslPlugin from "wesl-plugin/vite";
import { linkBuildExtension } from "wesl-plugin";
import { typegpuExtension } from "wesl-ext-typegpu";

export default defineConfig({
  plugins: [weslPlugin({ extensions: [linkBuildExtension, typegpuExtension] })],
});

And finally, to let the TypeScript language server know where to look for typing of the .wgsl/.wesl you’re importing, change the following in your tsconfig.json:

{
  // ...
  "include": [/* all other files you're including */, ".wesl/**/*"]
  // ...
}

Reflection

Let’s say we have to following shader program, split across two files.

struct BoidState {
  position: vec3f,
  velocity: vec3f,
}

struct Fish {
  kind: u32,
  state: BoidState,
}

use package::shared::Fish;

@group(0) @binding(0) var<storage, read_write> fish: array<Fish>;

@compute @workgroup_size(32)
fn main() {
  // ...
}

Given a shader written in WGSL/WESL, we can use the ?typegpu query parameter to import reified references to any struct definition.

// Importing a WGSL struct into JS
import { 
import Fish
Fish } from './shaders/shared.wesl?typegpu';

const 
const FishArray: (n: number) => d.WgslArray<d.WgslStruct<{
    kind: d.U32;
    state: d.WgslStruct<{
        position: d.Vec3f;
        velocity: d.Vec3f;
    }>;
}>>
FishArray = (
n: number
n: number) => 
import d
d.
arrayOf<d.WgslStruct<{
    kind: d.U32;
    state: d.WgslStruct<{
        position: d.Vec3f;
        velocity: d.Vec3f;
    }>;
}>>(elementType: d.WgslStruct<{
    kind: d.U32;
    state: d.WgslStruct<{
        position: d.Vec3f;
        velocity: d.Vec3f;
    }>;
}>, elementCount: number): d.WgslArray<...>
export arrayOf
Creates an array schema that can be used to construct gpu buffers.
Describes arrays with fixed-size length, storing elements of the same type.
@example const LENGTH = 3;
const array = d.arrayOf(d.u32, LENGTH);
@param ― elementType The type of elements in the array.
@param ― elementCount The number of elements in the array.
arrayOf(
const Fish: d.WgslStruct<{
    kind: d.U32;
    state: d.WgslStruct<{
        position: d.Vec3f;
        velocity: d.Vec3f;
    }>;
}>
Fish, 
n: number
n);

const buffer = 
const root: TgpuRoot
root.
TgpuRoot.createBuffer<d.WgslArray<d.WgslStruct<{
    kind: d.U32;
    state: d.WgslStruct<{
        position: d.Vec3f;
        velocity: d.Vec3f;
    }>;
}>>>(typeSchema: d.WgslArray<d.WgslStruct<{
    kind: d.U32;
    state: d.WgslStruct<{
        position: d.Vec3f;
        velocity: d.Vec3f;
    }>;
}>>, initial?: {
    ...;
}[] | undefined): TgpuBuffer<...> (+1 overload)
Allocates memory on the GPU, allows passing data between host and shader.
@param ― typeSchema The type of data that this buffer will hold.
@param ― initial The initial value of the buffer. (optional)
createBuffer(
const FishArray: (n: number) => d.WgslArray<d.WgslStruct<{
    kind: d.U32;
    state: d.WgslStruct<{
        position: d.Vec3f;
        velocity: d.Vec3f;
    }>;
}>>
FishArray(512)).
TgpuBuffer<WgslArray<WgslStruct<{ kind: U32; state: WgslStruct<{ position: Vec3f; velocity: Vec3f; }>; }>>>.$usage<["storage"]>(usages_0: "storage"): TgpuBuffer<d.WgslArray<d.WgslStruct<{
    kind: d.U32;
    state: d.WgslStruct<{
        position: d.Vec3f;
        velocity: d.Vec3f;
    }>;
}>>> & StorageFlag
$usage('storage');
const buffer: TgpuBuffer<d.WgslArray<d.WgslStruct<{
    kind: d.U32;
    state: d.WgslStruct<{
        position: d.Vec3f;
        velocity: d.Vec3f;
    }>;
}>>> & StorageFlag

// Updating the 123rd fish's position
const buffer: TgpuBuffer<d.WgslArray<d.WgslStruct<{
    kind: d.U32;
    state: d.WgslStruct<{
        position: d.Vec3f;
        velocity: d.Vec3f;
    }>;
}>>> & StorageFlag
buffer.
TgpuBuffer<WgslArray<WgslStruct<{ kind: U32; state: WgslStruct<{ position: Vec3f; velocity: Vec3f; }>; }>>>.writePartial(data: {
    idx: number;
    value: {
        kind?: number | undefined;
        state?: {
            position?: d.v3f | undefined;
            velocity?: d.v3f | undefined;
        };
    };
}[]): void
writePartial([
  {
    
idx: number
idx: 123,
    
value: {
    kind?: number | undefined;
    state?: {
        position?: d.v3f | undefined;
        velocity?: d.v3f | undefined;
    };
}
value: {
      
state?: {
    position?: d.v3f | undefined;
    velocity?: d.v3f | undefined;
}
state: {
        posit 
posit: any
position
      },
    }
  }
]);