Skip to content

Instantly share code, notes, and snippets.

@greggman

greggman/README.md

Last active March 27, 2025 19:59
Show Gist options
  • Save greggman/d67fcf75b048506195286f75c6a19c6d to your computer and use it in GitHub Desktop.
Save greggman/d67fcf75b048506195286f75c6a19c6d to your computer and use it in GitHub Desktop.
Download ZIP
WebGPU SkyBox - with textureGatherEmu (2)
Raw
README.md
Raw
index.css
@import url(https://webgpufundamentals.org/webgpu/resources/webgpu-lesson.css);
html, body {
margin: 0; /* remove the default margin */
height: 100%; /* make the html,body fill the page */
}
canvas {
display: block; /* make the canvas act like a block */
width: 100%; /* make the canvas fill its container */
height: 100%;
}
Raw
index.html
<canvas></canvas>
Raw
index.js
// WebGPU SkyBox
// from https://webgpufundamentals.org/webgpu/webgpu-skybox-plus-environment-map.html
// see https://webgpufundamentals.org/webgpu/lessons/webgpu-utils.html#wgpu-matrix
import {mat4} from 'https://webgpufundamentals.org/3rdparty/wgpu-matrix.module.js';
import {primitives} from 'https://greggman.github.io/webgpu-utils/dist/1.x/webgpu-utils.module.js';
import GUI from 'https://muigui.org/dist/0.x/muigui.module.js';
function createCubeVertices() {
const vertexData = new Float32Array([
// position | normals
//-------------+----------------------
// front face positive z
-1, 1, 1, 0, 0, 1,
-1, -1, 1, 0, 0, 1,
1, 1, 1, 0, 0, 1,
1, -1, 1, 0, 0, 1,
// right face positive x
1, 1, -1, 1, 0, 0,
1, 1, 1, 1, 0, 0,
1, -1, -1, 1, 0, 0,
1, -1, 1, 1, 0, 0,
// back face negative z
1, 1, -1, 0, 0, -1,
1, -1, -1, 0, 0, -1,
-1, 1, -1, 0, 0, -1,
-1, -1, -1, 0, 0, -1,
// left face negative x
-1, 1, 1, -1, 0, 0,
-1, 1, -1, -1, 0, 0,
-1, -1, 1, -1, 0, 0,
-1, -1, -1, -1, 0, 0,
// bottom face negative y
1, -1, 1, 0, -1, 0,
-1, -1, 1, 0, -1, 0,
1, -1, -1, 0, -1, 0,
-1, -1, -1, 0, -1, 0,
// top face positive y
-1, 1, 1, 0, 1, 0,
1, 1, 1, 0, 1, 0,
-1, 1, -1, 0, 1, 0,
1, 1, -1, 0, 1, 0,
]);
const indexData = new Uint16Array([
0, 1, 2, 2, 1, 3, // front
4, 5, 6, 6, 5, 7, // right
8, 9, 10, 10, 9, 11, // back
12, 13, 14, 14, 13, 15, // left
16, 17, 18, 18, 17, 19, // bottom
20, 21, 22, 22, 21, 23, // top
]);
return {
vertexData,
indexData,
numVertices: indexData.length,
};
}
async function main() {
const adapter = await navigator.gpu?.requestAdapter();
const device = await adapter?.requestDevice();
if (!device) {
fail('need a browser that supports WebGPU');
return;
}
device.addEventListener('uncapturederror', e => console.error(e.error.message));
// Get a WebGPU context from the canvas and configure it
const canvas = document.querySelector('canvas');
const context = canvas.getContext('webgpu');
const presentationFormat = navigator.gpu.getPreferredCanvasFormat();
context.configure({
device,
format: presentationFormat,
alphaMode: 'premultiplied',
});
const textureGatherWGSL = `
const faceNdx = array(
vec3i(-3, -2, 0), // 0 [-z, -y, aX]
vec3i( 3, -2, 1), // 1 [ z, -y, aX]
vec3i( 1, 3, 2), // 2 [ x, z, aY]
vec3i( 1, -3, 3), // 3 [ x, -z, aY]
vec3i( 1, -2, 4), // 4 [ x, -y, aZ]
vec3i(-1, -2, 5), // 5 [-x, -y, aZ]
);
fn convertCubeCoordToNormalized3DTextureCoord(v: vec3f) -> vec3f {
let r = normalize(v);
let absR = abs(r);
// +----+---- Each of these is the axis index (x =1, y = 2, z = 3) and the sign.
// | |
// | | +- Layer
// V V V
// 0 [-z, -y, aX] [-3, -2, 0]
// 1 [ z, -y, aX] [ 3, -2, 1]
// 2 [ x, z, aY] [ 1, 3, 2]
// 3 [ x, -z, aY] [ 1, -3, 3]
// 4 [ x, -y, aZ] [ 1, -2, 4]
// 5 [-x, -y, aZ] [-1, -2, 5]
var n: u32;
if (absR.x > absR.y && absR.x > absR.z) {
n = select(0u, 1u, r.x < 0.0);
} else if (absR.y > absR.z) {
n = select(2u, 3u, r.y < 0.0);
} else {
n = select(4u, 5u, r.z < 0.0);
}
let ndx = faceNdx[n];
let i = abs(ndx.xy) - 1;
let uvw = vec3f(vec2f(r[i.x], r[i.y]) * vec2f(sign(ndx.xy)), absR[ndx.z / 2]);
return vec3f((uvw.xy / uvw.z + 1.0) * 0.5, (f32(ndx.z) + 0.5) / 6.0);
}
fn convertCubeCoordToNormalized3DTextureCoord2(v: vec3f) -> vec3f {
var uvw: vec3f;
var layer: f32;
let r = normalize(v);
let absR = abs(r);
// 0 [-z, -y, aX]
// 1 [ z, -y, aX]
// 2 [ x, z, aY]
// 3 [ x, -z, aY]
// 4 [ x, -y, aZ]
// 5 [-x, -y, aZ]
if (absR.x > absR.y && absR.x > absR.z) {
// x major
if (r.x >= 0.0) {
uvw = vec3f(-r.z, -r.y, absR.x);
layer = 0;
} else {
uvw = vec3f(r.z, -r.y, absR.x);
layer = 1;
}
} else if (absR.y > absR.z) {
// y major
if (r.y >= 0.0) {
uvw = vec3f(r.x, r.z, absR.y);
layer = 2;
} else {
uvw = vec3f(r.x, -r.z, absR.y);
layer = 3;
}
} else {
// z major
if (r.z >= 0.0) {
uvw = vec3f(r.x, -r.y, absR.z);
layer = 4;
} else {
uvw = vec3f(-r.x, -r.y, absR.z);
layer = 5;
}
}
return vec3f((uvw.xy / uvw.z + 1.0) * 0.5, (layer + 0.5) / 6.0);
}
const faceMat = array(
mat3x3f( 0, 0, -2, 0, -2, 0, 1, 1, 1), // +x
mat3x3f( 0, 0, 2, 0, -2, 0, -1, 1, -1), // -x
mat3x3f( 2, 0, 0, 0, 0, 2, -1, 1, -1), // +y
mat3x3f( 2, 0, 0, 0, 0, -2, -1, -1, 1), // -y
mat3x3f( 2, 0, 0, 0, -2, 0, -1, 1, 1), // +z
mat3x3f(-2, 0, 0, 0, -2, 0, 1, 1, -1)); // -z
fn convertNormalized3DTexCoordToCubeCoord(uvLayer: vec3f) -> vec3f {
let layer = u32(uvLayer.z * 6.0);
return normalize(faceMat[layer] * vec3f(uvLayer.xy, 1));
}
fn textureGatherCubeEmu(component: u32, t: texture_cube<f32>, s: sampler, coord: vec3f) -> vec4f {
let uvLayer = convertCubeCoordToNormalized3DTextureCoord(coord);
let size = vec2f(textureDimensions(t));
let texelCoord = uvLayer.xy * size - 0.5;
let lo = floor(texelCoord);
let hi = ceil(texelCoord);
var coords: array<vec2f, 4>;
coords[0] = vec2f(lo.x, hi.y);
coords[1] = hi;
coords[2] = vec2f(hi.x, lo.y);
coords[3] = lo;
var texel: vec4f;
for (var i = 0; i < 4; i++) {
let uv = (coords[i] + 0.5) / size;
let cubeCoord = convertNormalized3DTexCoordToCubeCoord(vec3f(uv, uvLayer.z));
//let value = textureSampleLevel(t, s, cubeCoord, 0);
//let uvl = convertCubeCoordToNormalized3DTextureCoord(cubeCoord);
//let newCubeCoord = convertNormalized3DTexCoordToCubeCoord(uvl);
//let value = textureSampleLevel(t, s, newCubeCoord, 0);
// convert back to uvLayer so we can quantize
let uvl = convertCubeCoordToNormalized3DTextureCoord(cubeCoord);
let txlCoord = floor(uv.xy * size);
let newUv = (txlCoord + 0.5) / size;
let newCubeCoord = convertNormalized3DTexCoordToCubeCoord(vec3f(newUv, uvl.z));
let value = textureSampleLevel(t, s, newCubeCoord, 0);
texel[i] = value[component];
}
return texel;
}
fn avg(v: vec4f) -> f32 {
return (v.x + v.y + v.z + v.w) / 4.0;
}
fn textureSampleEmuOnGatherEmu(t: texture_cube<f32>, s: sampler, coord: vec3f) -> vec4f {
let r = textureGatherCubeEmu(0, ourTexture, ourSampler, coord);
let g = textureGatherCubeEmu(1, ourTexture, ourSampler, coord);
let b = textureGatherCubeEmu(2, ourTexture, ourSampler, coord);
let a = textureGatherCubeEmu(3, ourTexture, ourSampler, coord);
return vec4f(avg(r), avg(g), avg(b), avg(a));
}
fn textureSampleEmuOnGather(t: texture_cube<f32>, s: sampler, coord: vec3f) -> vec4f {
let r = textureGather(0, ourTexture, ourSampler, coord);
let g = textureGather(1, ourTexture, ourSampler, coord);
let b = textureGather(2, ourTexture, ourSampler, coord);
let a = textureGather(3, ourTexture, ourSampler, coord);
return vec4f(avg(r), avg(g), avg(b), avg(a));
}
`;
const skyBoxModule = device.createShaderModule({
code: `
${textureGatherWGSL}
struct Uniforms {
viewDirectionProjectionInverse: mat4x4f,
};
struct VSOutput {
@builtin(position) position: vec4f,
@location(0) pos: vec4f,
};
@group(0) @binding(0) var<uniform> uni: Uniforms;
@group(0) @binding(1) var ourSampler: sampler;
@group(0) @binding(2) var ourTexture: texture_cube<f32>;
@vertex fn vs(@builtin(vertex_index) vNdx: u32) -> VSOutput {
let pos = array(
vec2f(-1, 3),
vec2f(-1,-1),
vec2f( 3,-1),
);
var vsOut: VSOutput;
vsOut.position = vec4f(pos[vNdx], 1, 1);
vsOut.pos = vsOut.position;
return vsOut;
}
@fragment fn fs(vsOut: VSOutput) -> @location(0) vec4f {
let t = uni.viewDirectionProjectionInverse * vsOut.pos;
return textureSampleEmuOnGatherEmu(ourTexture, ourSampler, normalize(t.xyz / t.w) * vec3f(1, 1, -1));
}
`,
});
const skyBoxPipeline = device.createRenderPipeline({
label: 'no attributes',
layout: 'auto',
vertex: {
module: skyBoxModule,
},
fragment: {
module: skyBoxModule,
targets: [{ format: presentationFormat }],
},
depthStencil: {
depthWriteEnabled: true,
depthCompare: 'less-equal',
format: 'depth24plus',
},
});
const envMapModule = device.createShaderModule({
code: `
${textureGatherWGSL}
struct Uniforms {
projection: mat4x4f,
view: mat4x4f,
world: mat4x4f,
cameraPosition: vec3f,
};
struct Vertex {
@location(0) position: vec4f,
@location(1) normal: vec3f,
};
struct VSOutput {
@builtin(position) position: vec4f,
@location(0) worldPosition: vec3f,
@location(1) worldNormal: vec3f,
};
@group(0) @binding(0) var<uniform> uni: Uniforms;
@group(0) @binding(1) var ourSampler: sampler;
@group(0) @binding(2) var ourTexture: texture_cube<f32>;
@vertex fn vs(vert: Vertex) -> VSOutput {
var vsOut: VSOutput;
vsOut.position = uni.projection * uni.view * uni.world * vert.position;
vsOut.worldPosition = (uni.world * vert.position).xyz;
vsOut.worldNormal = (uni.world * vec4f(vert.normal, 0)).xyz;
return vsOut;
}
@fragment fn fs(vsOut: VSOutput) -> @location(0) vec4f {
let worldNormal = normalize(vsOut.worldNormal);
let eyeToSurfaceDir = normalize(vsOut.worldPosition - uni.cameraPosition);
let direction = reflect(eyeToSurfaceDir, worldNormal);
//return textureSample(ourTexture, ourSampler, direction * vec3f(1, 1, -1));
//return textureSampleEmuOnGather(ourTexture, ourSampler, direction * vec3f(1, 1, -1));
return textureSampleEmuOnGatherEmu(ourTexture, ourSampler, direction * vec3f(1, 1, -1));
}
`,
});
const envMapPipeline = device.createRenderPipeline({
label: '2 attributes',
layout: 'auto',
vertex: {
module: envMapModule,
buffers: [
{
arrayStride: (3) * 4, // (3) floats 4 bytes each
attributes: [
{shaderLocation: 0, offset: 0, format: 'float32x3'}, // position
],
},
{
arrayStride: (3) * 4, // (3) floats 4 bytes each
attributes: [
{shaderLocation: 1, offset: 0, format: 'float32x3'}, // normal
],
},
],
},
fragment: {
module: envMapModule,
targets: [{ format: presentationFormat }],
},
primitive: {
cullMode: 'back',
},
depthStencil: {
depthWriteEnabled: true,
depthCompare: 'less',
format: 'depth24plus',
},
});
const numMipLevels = (...sizes) => {
const maxSize = Math.max(...sizes);
return 1 + Math.log2(maxSize) | 0;
};
function copySourcesToTexture(device, texture, sources, {flipY} = {}) {
sources.forEach((source, layer) => {
device.queue.copyExternalImageToTexture(
{ source, flipY, },
{ texture, origin: [0, 0, layer] },
{ width: source.width, height: source.height },
);
});
if (texture.mipLevelCount > 1) {
generateMips(device, texture);
}
}
function createTextureFromSources(device, sources, options = {}) {
// Assume are sources all the same size so just use the first one for width and height
const source = sources[0];
const texture = device.createTexture({
format: 'rgba8unorm',
mipLevelCount: options.mips ? numMipLevels(source.width, source.height) : 1,
size: [source.width, source.height, sources.length],
usage: GPUTextureUsage.TEXTURE_BINDING |
GPUTextureUsage.COPY_DST |
GPUTextureUsage.RENDER_ATTACHMENT,
});
copySourcesToTexture(device, texture, sources, options);
return texture;
}
const generateMips = (() => {
let sampler;
let module;
const pipelineByFormat = {};
return function generateMips(device, texture) {
if (!module) {
module = device.createShaderModule({
label: 'textured quad shaders for mip level generation',
code: `
struct VSOutput {
@builtin(position) position: vec4f,
@location(0) texcoord: vec2f,
};
@vertex fn vs(
@builtin(vertex_index) vertexIndex : u32
) -> VSOutput {
let pos = array(
vec2f( 0.0, 0.0), // center
vec2f( 1.0, 0.0), // right, center
vec2f( 0.0, 1.0), // center, top
// 2st triangle
vec2f( 0.0, 1.0), // center, top
vec2f( 1.0, 0.0), // right, center
vec2f( 1.0, 1.0), // right, top
);
var vsOutput: VSOutput;
let xy = pos[vertexIndex];
vsOutput.position = vec4f(xy * 2.0 - 1.0, 0.0, 1.0);
vsOutput.texcoord = vec2f(xy.x, 1.0 - xy.y);
return vsOutput;
}
@group(0) @binding(0) var ourSampler: sampler;
@group(0) @binding(1) var ourTexture: texture_2d<f32>;
@fragment fn fs(fsInput: VSOutput) -> @location(0) vec4f {
return textureSample(ourTexture, ourSampler, fsInput.texcoord);
}
`,
});
sampler = device.createSampler({
minFilter: 'linear',
magFilter: 'linear',
});
}
if (!pipelineByFormat[texture.format]) {
pipelineByFormat[texture.format] = device.createRenderPipeline({
label: 'mip level generator pipeline',
layout: 'auto',
vertex: {
module,
},
fragment: {
module,
targets: [{ format: texture.format }],
},
});
}
const pipeline = pipelineByFormat[texture.format];
const encoder = device.createCommandEncoder({
label: 'mip gen encoder',
});
for (let baseMipLevel = 1; baseMipLevel < texture.mipLevelCount; ++baseMipLevel) {
for (let layer = 0; layer < texture.depthOrArrayLayers; ++layer) {
const bindGroup = device.createBindGroup({
layout: pipeline.getBindGroupLayout(0),
entries: [
{ binding: 0, resource: sampler },
{
binding: 1,
resource: texture.createView({
dimension: '2d',
baseMipLevel: baseMipLevel - 1,
mipLevelCount: 1,
baseArrayLayer: layer,
arrayLayerCount: 1,
}),
},
],
});
const renderPassDescriptor = {
label: 'our basic canvas renderPass',
colorAttachments: [
{
view: texture.createView({
dimension: '2d',
baseMipLevel: baseMipLevel,
mipLevelCount: 1,
baseArrayLayer: layer,
arrayLayerCount: 1,
}),
loadOp: 'clear',
storeOp: 'store',
},
],
};
const pass = encoder.beginRenderPass(renderPassDescriptor);
pass.setPipeline(pipeline);
pass.setBindGroup(0, bindGroup);
pass.draw(6); // call our vertex shader 6 times
pass.end();
}
}
const commandBuffer = encoder.finish();
device.queue.submit([commandBuffer]);
};
})();
async function loadImageBitmap(url) {
const res = await fetch(url);
const blob = await res.blob();
return await createImageBitmap(blob, { colorSpaceConversion: 'none' });
}
async function createTextureFromImages(device, urls, options) {
const images = await Promise.all(urls.map(loadImageBitmap));
return createTextureFromSources(device, images, options);
}
//const texture = await createTextureFromImages(
// device,
// [
// 'https://webgpufundamentals.org/webgpu/resources/images/leadenhall_market/pos-x.jpg',
// 'https://webgpufundamentals.org/webgpu/resources/images/leadenhall_market/neg-x.jpg',
// 'https://webgpufundamentals.org/webgpu/resources/images/leadenhall_market/pos-y.jpg',
// 'https://webgpufundamentals.org/webgpu/resources/images/leadenhall_market/neg-y.jpg',
// 'https://webgpufundamentals.org/webgpu/resources/images/leadenhall_market/pos-z.jpg',
// 'https://webgpufundamentals.org/webgpu/resources/images/leadenhall_market/neg-z.jpg',
// ],
// {mips: true, flipY: false},
//);
const texture = createTextureFromSources(device, [
makeCanvasImage({ width: 64, height: 64, borderColor: '#f00', backgroundColor: '#f00', foregroundColor: '#fff', text: ['+x'] }),
makeCanvasImage({ width: 64, height: 64, borderColor: '#0f0', backgroundColor: '#0f0', foregroundColor: '#fff', text: ['-x'] }),
makeCanvasImage({ width: 64, height: 64, borderColor: '#00f', backgroundColor: '#00f', foregroundColor: '#fff', text: ['+y'] }),
makeCanvasImage({ width: 64, height: 64, borderColor: '#800', backgroundColor: '#800', foregroundColor: '#fff', text: ['-y'] }),
makeCanvasImage({ width: 64, height: 64, borderColor: '#080', backgroundColor: '#080', foregroundColor: '#fff', text: ['+z'] }),
makeCanvasImage({ width: 64, height: 64, borderColor: '#008', backgroundColor: '#008', foregroundColor: '#fff', text: ['-z'] }),
], { mips: true })
const sampler = device.createSampler({
magFilter: 'linear',
minFilter: 'linear',
mipmapFilter: 'linear',
});
// viewDirectionProjectionInverse
const skyBoxUniformBufferSize = (16) * 4;
const skyBoxUniformBuffer = device.createBuffer({
label: 'uniforms',
size: skyBoxUniformBufferSize,
usage: GPUBufferUsage.UNIFORM | GPUBufferUsage.COPY_DST,
});
const skyBoxUniformValues = new Float32Array(skyBoxUniformBufferSize / 4);
// offsets to the various uniform values in float32 indices
const kViewDirectionProjectionInverseOffset = 0;
const viewDirectionProjectionInverseValue = skyBoxUniformValues.subarray(
kViewDirectionProjectionInverseOffset,
kViewDirectionProjectionInverseOffset + 16);
// projection, view, world, cameraPosition, pad
const envMapUniformBufferSize = (16 + 16 + 16 + 3 + 1) * 4;
const envMapUniformBuffer = device.createBuffer({
label: 'uniforms',
size: envMapUniformBufferSize,
usage: GPUBufferUsage.UNIFORM | GPUBufferUsage.COPY_DST,
});
const envMapUniformValues = new Float32Array(envMapUniformBufferSize / 4);
// offsets to the various uniform values in float32 indices
const kProjectionOffset = 0;
const kViewOffset = 16;
const kWorldOffset = 32;
const kCameraPositionOffset = 48;
const projectionValue = envMapUniformValues.subarray(kProjectionOffset, kProjectionOffset + 16);
const viewValue = envMapUniformValues.subarray(kViewOffset, kViewOffset + 16);
const worldValue = envMapUniformValues.subarray(kWorldOffset, kWorldOffset + 16);
const cameraPositionValue = envMapUniformValues.subarray(
kCameraPositionOffset, kCameraPositionOffset + 3);
//const { vertexData, indexData, numVertices } = createCubeVertices();
const { position, normal, indices } = primitives.createSphereVertices({
subdivisionsAxis: 64,
subdivisionsHeight: 32,
});
const positionData = new Float32Array(position);
const normalData = new Float32Array(normal);
const indexData = new Uint16Array(indices);
const positionBuffer = device.createBuffer({
label: 'position buffer vertices',
size: positionData.byteLength,
usage: GPUBufferUsage.VERTEX | GPUBufferUsage.COPY_DST,
});
device.queue.writeBuffer(positionBuffer, 0, positionData);
const normalBuffer = device.createBuffer({
label: 'normal buffer vertices',
size: normalData.byteLength,
usage: GPUBufferUsage.VERTEX | GPUBufferUsage.COPY_DST,
});
device.queue.writeBuffer(normalBuffer, 0, normalData);
const indexBuffer = device.createBuffer({
label: 'index buffer',
size: indexData.byteLength,
usage: GPUBufferUsage.INDEX | GPUBufferUsage.COPY_DST,
});
device.queue.writeBuffer(indexBuffer, 0, indexData);
const envMapBindGroup = device.createBindGroup({
label: 'bind group for object',
layout: envMapPipeline.getBindGroupLayout(0),
entries: [
{ binding: 0, resource: { buffer: envMapUniformBuffer }},
{ binding: 1, resource: sampler },
{ binding: 2, resource: texture.createView({dimension: 'cube'}) },
],
});
const renderPassDescriptor = {
label: 'our basic canvas renderPass',
colorAttachments: [
{
// view: <- to be filled out when we render
loadOp: 'clear',
storeOp: 'store',
},
],
depthStencilAttachment: {
// view: <- to be filled out when we render
depthClearValue: 1.0,
depthLoadOp: 'clear',
depthStoreOp: 'store',
},
};
let depthTexture;
const skyBoxBindGroups = new Map();
const radToDegOptions = { min: -1, max: 179, step: 1, converters: GUI.converters.radToDeg };
const settings = {
skyBoxBaseMipLevel: 3,
cameraRadius: 2,
fov: 120 * Math.PI / 180,
};
const gui = new GUI();
gui.add(settings, 'skyBoxBaseMipLevel', 0, 9, 1);
gui.add(settings, 'cameraRadius', 2, 10);
gui.add(settings, 'fov', radToDegOptions);
function render(time) {
time *= 0.001;
const baseMipLevel = Math.min(settings.skyBoxBaseMipLevel, texture.mipLevelCount - 1);
const skyBoxBindGroup = skyBoxBindGroups.get(baseMipLevel) ?? device.createBindGroup({
label: 'bind group for object',
layout: skyBoxPipeline.getBindGroupLayout(0),
entries: [
{ binding: 0, resource: { buffer: skyBoxUniformBuffer }},
{ binding: 1, resource: sampler },
{ binding: 2, resource: texture.createView({dimension: 'cube', baseMipLevel}) },
],
});
skyBoxBindGroups.set(baseMipLevel, skyBoxBindGroup);
// Get the current texture from the canvas context and
// set it as the texture to render to.
const canvasTexture = context.getCurrentTexture();
renderPassDescriptor.colorAttachments[0].view = canvasTexture.createView();
// If we don't have a depth texture OR if its size is different
// from the canvasTexture when make a new depth texture
if (!depthTexture ||
depthTexture.width !== canvasTexture.width ||
depthTexture.height !== canvasTexture.height) {
if (depthTexture) {
depthTexture.destroy();
}
depthTexture = device.createTexture({
size: [canvasTexture.width, canvasTexture.height],
format: 'depth24plus',
usage: GPUTextureUsage.RENDER_ATTACHMENT,
});
}
renderPassDescriptor.depthStencilAttachment.view = depthTexture.createView();
const encoder = device.createCommandEncoder();
const pass = encoder.beginRenderPass(renderPassDescriptor);
const aspect = canvas.clientWidth / canvas.clientHeight;
mat4.perspective(
settings.fov,
aspect,
0.1, // zNear
10, // zFar
projectionValue,
);
// Camera going in circle from origin looking at origin
const r = settings.cameraRadius;
cameraPositionValue.set([Math.cos(time * .1) * r, 0, Math.sin(time * .1) * r]);
const view = mat4.lookAt(
cameraPositionValue,
[0, 0, 0], // target
[0, 1, 0], // up
);
// Copy the view into the viewValue since we're going
// to zero out the view's translation
viewValue.set(view);
// We only care about direction so remove the translation
view[12] = 0;
view[13] = 0;
view[14] = 0;
const viewProjection = mat4.multiply(projectionValue, view);
mat4.inverse(viewProjection, viewDirectionProjectionInverseValue);
// Rotate the cube
mat4.identity(worldValue);
mat4.rotateX(worldValue, time * -0.1, worldValue);
mat4.rotateY(worldValue, time * -0.2, worldValue);
// upload the uniform values to the uniform buffers
device.queue.writeBuffer(envMapUniformBuffer, 0, envMapUniformValues);
device.queue.writeBuffer(skyBoxUniformBuffer, 0, skyBoxUniformValues);
// Draw the cube
pass.setPipeline(envMapPipeline);
pass.setVertexBuffer(0, positionBuffer);
pass.setVertexBuffer(1, normalBuffer);
pass.setIndexBuffer(indexBuffer, 'uint16');
pass.setBindGroup(0, envMapBindGroup);
pass.drawIndexed(indexBuffer.size / 2);
// Draw the skyBox
pass.setPipeline(skyBoxPipeline);
pass.setBindGroup(0, skyBoxBindGroup);
pass.draw(3);
pass.end();
const commandBuffer = encoder.finish();
device.queue.submit([commandBuffer]);
requestAnimationFrame(render);
}
requestAnimationFrame(render);
const observer = new ResizeObserver(entries => {
for (const entry of entries) {
const canvas = entry.target;
const width = entry.contentBoxSize[0].inlineSize;
const height = entry.contentBoxSize[0].blockSize;
canvas.width = Math.max(1, Math.min(width, device.limits.maxTextureDimension2D));
canvas.height = Math.max(1, Math.min(height, device.limits.maxTextureDimension2D));
}
});
observer.observe(canvas);
}
function fail(msg) {
alert(msg);
}
function makeCanvasImage({
width,
height,
borderColor,
backgroundColor,
foregroundColor,
font,
text,
}/*: {
width: number;
height: number;
borderColor: string;
backgroundColor: string;
foregroundColor: string;
font?: string;
text: string[];
}*/) {
const canvas = new OffscreenCanvas(width, height);
const ctx = canvas.getContext('2d');
ctx.fillStyle = borderColor;
ctx.fillRect(0, 0, width, height);
const borderSize = 10;
ctx.fillStyle = backgroundColor;
ctx.fillRect(
borderSize,
borderSize,
width - borderSize * 2,
height - borderSize * 2
);
ctx.fillStyle = foregroundColor;
ctx.font =
font ?? `${Math.ceil(Math.min(width, height) * 0.8)}px bold monospace`;
ctx.textAlign = 'left';
ctx.textBaseline = 'top';
for (const t of text) {
const m = ctx.measureText(t);
ctx.fillText(
t,
(width - m.actualBoundingBoxRight + m.actualBoundingBoxLeft) / 2,
(height - m.actualBoundingBoxDescent + m.actualBoundingBoxAscent) / 2
);
}
return canvas;
}
main();
Raw
jsGist.json
{"name":"WebGPU SkyBox - with textureGatherEmu (2)","settings":{},"filenames":["index.html","index.css","index.js"]}
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment