Files
webgpufundamentals/webgpu/webgpu-points-3d.html
Gregg Tavares dcfd514975 Revert "Use direct attachment binding"
This reverts commit bdce233195.
2026-02-04 12:17:44 -08:00

244 lines
6.6 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 Points - 3d</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%;
}
</style>
</head>
<body>
<canvas></canvas>
</body>
<script type="module">
// see https://webgpufundamentals.org/webgpu/lessons/webgpu-utils.html#wgpu-matrix
import {mat4} from '../3rdparty/wgpu-matrix.module.js';
function createFibonacciSphereVertices({
numSamples,
radius,
}) {
const vertices = [];
const increment = Math.PI * (3 - Math.sqrt(5));
for (let i = 0; i < numSamples; ++i) {
const offset = 2 / numSamples;
const y = ((i * offset) - 1) + (offset / 2);
const r = Math.sqrt(1 - Math.pow(y, 2));
const phi = (i % numSamples) * increment;
const x = Math.cos(phi) * r;
const z = Math.sin(phi) * r;
vertices.push(x * radius, y * radius, z * radius);
}
return new Float32Array(vertices);
}
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,
});
const module = device.createShaderModule({
code: /* wgsl */ `
struct Vertex {
@location(0) position: vec4f,
};
struct Uniforms {
matrix: mat4x4f,
resolution: vec2f,
size: f32,
};
struct VSOutput {
@builtin(position) position: vec4f,
};
@group(0) @binding(0) var<uniform> uni: Uniforms;
@vertex fn vs(
vert: Vertex,
@builtin(vertex_index) vNdx: u32,
) -> VSOutput {
let points = array(
vec2f(-1, -1),
vec2f( 1, -1),
vec2f(-1, 1),
vec2f(-1, 1),
vec2f( 1, -1),
vec2f( 1, 1),
);
var vsOut: VSOutput;
let pos = points[vNdx];
let clipPos = uni.matrix * vert.position;
let pointPos = vec4f(pos * uni.size / uni.resolution, 0, 0);
vsOut.position = clipPos + pointPos;
return vsOut;
}
@fragment fn fs(vsOut: VSOutput) -> @location(0) vec4f {
return vec4f(1, 0.5, 0.2, 1);
}
`,
});
const pipeline = device.createRenderPipeline({
label: '3d points',
layout: 'auto',
vertex: {
module,
buffers: [
{
arrayStride: (3) * 4, // 3 floats, 4 bytes each
stepMode: 'instance',
attributes: [
{shaderLocation: 0, offset: 0, format: 'float32x3'}, // position
],
},
],
},
fragment: {
module,
targets: [
{
format: presentationFormat,
},
],
},
});
const vertexData = createFibonacciSphereVertices({
radius: 1,
numSamples: 1000,
});
const kNumPoints = vertexData.length / 3;
const vertexBuffer = device.createBuffer({
label: 'vertex buffer vertices',
size: vertexData.byteLength,
usage: GPUBufferUsage.VERTEX | GPUBufferUsage.COPY_DST,
});
device.queue.writeBuffer(vertexBuffer, 0, vertexData);
const uniformValues = new Float32Array(16 + 2 + 1 + 1);
const uniformBuffer = device.createBuffer({
size: uniformValues.byteLength,
usage: GPUBufferUsage.UNIFORM | GPUBufferUsage.COPY_DST,
});
const kMatrixOffset = 0;
const kResolutionOffset = 16;
const kSizeOffset = 18;
const matrixValue = uniformValues.subarray(
kMatrixOffset, kMatrixOffset + 16);
const resolutionValue = uniformValues.subarray(
kResolutionOffset, kResolutionOffset + 2);
const sizeValue = uniformValues.subarray(
kSizeOffset, kSizeOffset + 1);
const bindGroup = device.createBindGroup({
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
clearValue: [0.3, 0.3, 0.3, 1],
loadOp: 'clear',
storeOp: 'store',
},
],
};
function render(time) {
time *= 0.001;
// 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();
// Set the size in the uniform values
sizeValue[0] = 10;
// Set the matrix in the uniform values
const fov = 90 * Math.PI / 180;
const aspect = canvas.clientWidth / canvas.clientHeight;
const projection = mat4.perspective(fov, aspect, 0.1, 50);
const view = mat4.lookAt(
[0, 0, 1.5], // position
[0, 0, 0], // target
[0, 1, 0], // up
);
const viewProjection = mat4.multiply(projection, view);
mat4.rotateY(viewProjection, time, matrixValue);
mat4.rotateX(matrixValue, time * 0.5, matrixValue);
// Update the resolution in the uniform values
resolutionValue.set([canvasTexture.width, canvasTexture.height]);
// Copy the uniform values to the GPU
device.queue.writeBuffer(uniformBuffer, 0, uniformValues);
const encoder = device.createCommandEncoder();
const pass = encoder.beginRenderPass(renderPassDescriptor);
pass.setPipeline(pipeline);
pass.setVertexBuffer(0, vertexBuffer);
pass.setBindGroup(0, bindGroup);
pass.draw(6, kNumPoints);
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);
}
main();
</script>
</html>