Files
webgpufundamentals/webgpu/webgpu-matrix-math-transform-srt.html
Gregg Tavares dcfd514975 Revert "Use direct attachment binding"
This reverts commit bdce233195.
2026-02-04 12:17:44 -08:00

360 lines
9.5 KiB
HTML

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes">
<title>WebGPU Matrix Transform TRS</title>
<style>
@import url(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%;
}
:root {
--bg-color: #fff;
--line-color-1: #AAA;
--line-color-2: #DDD;
}
@media (prefers-color-scheme: dark) {
:root {
--bg-color: #000;
--line-color-1: #666;
--line-color-2: #333;
}
}
canvas {
display: block; /* make the canvas act like a block */
width: 100%; /* make the canvas fill its container */
height: 100%;
background-color: var(--bg-color);
background-image: linear-gradient(var(--line-color-1) 1.5px, transparent 1.5px),
linear-gradient(90deg, var(--line-color-1) 1.5px, transparent 1.5px),
linear-gradient(var(--line-color-2) 1px, transparent 1px),
linear-gradient(90deg, var(--line-color-2) 1px, transparent 1px);
background-position: -1.5px -1.5px, -1.5px -1.5px, -1px -1px, -1px -1px;
background-size: 100px 100px, 100px 100px, 10px 10px, 10px 10px;
}
</style>
</head>
<body>
<canvas></canvas>
</body>
<script type="module">
import GUI from '../3rdparty/muigui-0.x.module.js';
function createFVertices() {
const vertexData = new Float32Array([
// left column
0, 0,
30, 0,
0, 150,
30, 150,
// top rung
30, 0,
100, 0,
30, 30,
100, 30,
// middle rung
30, 60,
70, 60,
30, 90,
70, 90,
]);
const indexData = new Uint32Array([
0, 1, 2, 2, 1, 3, // left column
4, 5, 6, 6, 5, 7, // top run
8, 9, 10, 10, 9, 11, // middle run
]);
return {
vertexData,
indexData,
numVertices: indexData.length,
};
}
const mat3 = {
multiply(a, b) {
const a00 = a[0 * 4 + 0];
const a01 = a[0 * 4 + 1];
const a02 = a[0 * 4 + 2];
const a10 = a[1 * 4 + 0];
const a11 = a[1 * 4 + 1];
const a12 = a[1 * 4 + 2];
const a20 = a[2 * 4 + 0];
const a21 = a[2 * 4 + 1];
const a22 = a[2 * 4 + 2];
const b00 = b[0 * 4 + 0];
const b01 = b[0 * 4 + 1];
const b02 = b[0 * 4 + 2];
const b10 = b[1 * 4 + 0];
const b11 = b[1 * 4 + 1];
const b12 = b[1 * 4 + 2];
const b20 = b[2 * 4 + 0];
const b21 = b[2 * 4 + 1];
const b22 = b[2 * 4 + 2];
return [
b00 * a00 + b01 * a10 + b02 * a20,
b00 * a01 + b01 * a11 + b02 * a21,
b00 * a02 + b01 * a12 + b02 * a22,
0,
b10 * a00 + b11 * a10 + b12 * a20,
b10 * a01 + b11 * a11 + b12 * a21,
b10 * a02 + b11 * a12 + b12 * a22,
0,
b20 * a00 + b21 * a10 + b22 * a20,
b20 * a01 + b21 * a11 + b22 * a21,
b20 * a02 + b21 * a12 + b22 * a22,
0,
];
},
translation([tx, ty]) {
return [
1, 0, 0, 0,
0, 1, 0, 0,
tx, ty, 1, 0,
];
},
rotation(angleInRadians) {
const c = Math.cos(angleInRadians);
const s = Math.sin(angleInRadians);
return [
c, s, 0, 0,
-s, c, 0, 0,
0, 0, 1, 0,
];
},
scaling([sx, sy]) {
return [
sx, 0, 0, 0,
0, sy, 0, 0,
0, 0, 1, 0,
];
},
};
async function main() {
const adapter = await navigator.gpu?.requestAdapter();
const device = await adapter?.requestDevice();
if (!device) {
fail('need a browser that supports WebGPU');
return;
}
// 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 module = device.createShaderModule({
code: /* wgsl */ `
struct Uniforms {
color: vec4f,
resolution: vec2f,
matrix: mat3x3f,
};
struct Vertex {
@location(0) position: vec2f,
};
struct VSOutput {
@builtin(position) position: vec4f,
};
@group(0) @binding(0) var<uniform> uni: Uniforms;
@vertex fn vs(vert: Vertex) -> VSOutput {
var vsOut: VSOutput;
// Multiply by a matrix
let position = (uni.matrix * vec3f(vert.position, 1)).xy;
// convert the position from pixels to a 0.0 to 1.0 value
let zeroToOne = position / uni.resolution;
// convert from 0 <-> 1 to 0 <-> 2
let zeroToTwo = zeroToOne * 2.0;
// covert from 0 <-> 2 to -1 <-> +1 (clip space)
let flippedClipSpace = zeroToTwo - 1.0;
// flip Y
let clipSpace = flippedClipSpace * vec2f(1, -1);
vsOut.position = vec4f(clipSpace, 0.0, 1.0);
return vsOut;
}
@fragment fn fs(vsOut: VSOutput) -> @location(0) vec4f {
return uni.color;
}
`,
});
const pipeline = device.createRenderPipeline({
label: 'just 2d position',
layout: 'auto',
vertex: {
module,
buffers: [
{
arrayStride: (2) * 4, // (2) floats, 4 bytes each
attributes: [
{shaderLocation: 0, offset: 0, format: 'float32x2'}, // position
],
},
],
},
fragment: {
module,
targets: [{ format: presentationFormat }],
},
});
// color, resolution, padding, matrix
const uniformBufferSize = (4 + 2 + 2 + 12) * 4;
const uniformBuffer = device.createBuffer({
label: 'uniforms',
size: uniformBufferSize,
usage: GPUBufferUsage.UNIFORM | GPUBufferUsage.COPY_DST,
});
const uniformValues = new Float32Array(uniformBufferSize / 4);
// offsets to the various uniform values in float32 indices
const kColorOffset = 0;
const kResolutionOffset = 4;
const kMatrixOffset = 8;
const colorValue = uniformValues.subarray(kColorOffset, kColorOffset + 4);
const resolutionValue = uniformValues.subarray(kResolutionOffset, kResolutionOffset + 2);
const matrixValue = uniformValues.subarray(kMatrixOffset, kMatrixOffset + 12);
// The color will not change so let's set it once at init time
colorValue.set([Math.random(), Math.random(), Math.random(), 1]);
const { vertexData, indexData, numVertices } = createFVertices();
const vertexBuffer = device.createBuffer({
label: 'vertex buffer vertices',
size: vertexData.byteLength,
usage: GPUBufferUsage.VERTEX | GPUBufferUsage.COPY_DST,
});
device.queue.writeBuffer(vertexBuffer, 0, vertexData);
const indexBuffer = device.createBuffer({
label: 'index buffer',
size: indexData.byteLength,
usage: GPUBufferUsage.INDEX | GPUBufferUsage.COPY_DST,
});
device.queue.writeBuffer(indexBuffer, 0, indexData);
const bindGroup = device.createBindGroup({
label: 'bind group for object',
layout: pipeline.getBindGroupLayout(0),
entries: [
{ binding: 0, resource: uniformBuffer },
],
});
const renderPassDescriptor = {
label: 'our basic canvas renderPass',
colorAttachments: [
{
// view: <- to be filled out when we render
loadOp: 'clear',
storeOp: 'store',
},
],
};
const degToRad = d => d * Math.PI / 180;
const settings = {
translation: [150, 100],
rotation: degToRad(30),
scale: [1, 1],
};
const radToDegOptions = { min: -360, max: 360, step: 1, converters: GUI.converters.radToDeg };
const gui = new GUI();
gui.onChange(render);
gui.add(settings.translation, '0', 0, 1000).name('translation.x');
gui.add(settings.translation, '1', 0, 1000).name('translation.y');
gui.add(settings, 'rotation', radToDegOptions);
gui.add(settings.scale, '0', -5, 5).name('scale.x');
gui.add(settings.scale, '1', -5, 5).name('scale.y');
function render() {
// Get the current texture from the canvas context and
// set it as the texture to render to.
renderPassDescriptor.colorAttachments[0].view =
context.getCurrentTexture().createView();
const encoder = device.createCommandEncoder();
const pass = encoder.beginRenderPass(renderPassDescriptor);
pass.setPipeline(pipeline);
pass.setVertexBuffer(0, vertexBuffer);
pass.setIndexBuffer(indexBuffer, 'uint32');
const translationMatrix = mat3.translation(settings.translation);
const rotationMatrix = mat3.rotation(settings.rotation);
const scaleMatrix = mat3.scaling(settings.scale);
let matrix = mat3.multiply(translationMatrix, rotationMatrix);
matrix = mat3.multiply(matrix, scaleMatrix);
// Set the uniform values in our JavaScript side Float32Array
resolutionValue.set([canvas.width, canvas.height]);
matrixValue.set(matrix);
// upload the uniform values to the uniform buffer
device.queue.writeBuffer(uniformBuffer, 0, uniformValues);
pass.setBindGroup(0, bindGroup);
pass.drawIndexed(numVertices);
pass.end();
const commandBuffer = encoder.finish();
device.queue.submit([commandBuffer]);
}
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));
// re-render
render();
}
});
observer.observe(canvas);
}
function fail(msg) {
alert(msg);
}
main();
</script>
</html>