fleeting-garden/src/pipelines/diffusion/diffusion-pipeline.ts
2023-04-29 11:58:14 +01:00

124 lines
3.1 KiB
TypeScript

import { setUpFullScreenQuad } from '../../utils/full-screen-quad';
import { CommonParameters } from '../common-parameters';
import shader from './diffuse.wgsl';
import { DiffusionSettings } from './diffusion-settings';
export class DiffusionPipeline {
private static readonly UNIFORM_COUNT = 16;
private readonly pipeline: GPURenderPipeline;
private readonly uniforms: GPUBuffer;
private readonly quadVertexBuffer: GPUBuffer;
private bindGroup?: GPUBindGroup;
private previousTrailMapIn?: GPUTexture;
public constructor(private readonly device: GPUDevice) {
const { buffer, vertex } = setUpFullScreenQuad(device);
this.quadVertexBuffer = buffer;
this.pipeline = device.createRenderPipeline({
layout: 'auto',
vertex,
fragment: {
module: device.createShaderModule({
code: shader,
}),
entryPoint: 'fragment',
targets: [
{
format: 'rgba16float',
},
],
},
primitive: {
topology: 'triangle-strip',
},
});
this.uniforms = this.device.createBuffer({
size: DiffusionPipeline.UNIFORM_COUNT * Float32Array.BYTES_PER_ELEMENT,
usage: GPUBufferUsage.UNIFORM | GPUBufferUsage.COPY_DST,
});
}
public setParameters({
canvasSize,
deltaTime,
time,
diffusionRate,
decayRate,
swipeRadius,
swipeBlur,
}: CommonParameters & DiffusionSettings) {
this.device.queue.writeBuffer(
this.uniforms,
0,
new Float32Array([
canvasSize[0],
canvasSize[1],
deltaTime,
time,
diffusionRate,
decayRate,
swipeRadius,
swipeBlur,
])
);
}
public execute(
commandEncoder: GPUCommandEncoder,
trailMapIn: GPUTexture,
trailMapOut: GPUTexture
) {
this.ensureBindGroupExists(trailMapIn);
const renderPassDescriptor: GPURenderPassDescriptor = {
colorAttachments: [
{
view: trailMapOut.createView(),
clearValue: { r: 1.0, g: 1.0, b: 1.0, a: 1.0 },
loadOp: 'clear',
storeOp: 'store',
},
],
};
const passEncoder = commandEncoder.beginRenderPass(renderPassDescriptor);
passEncoder.setPipeline(this.pipeline);
passEncoder.setVertexBuffer(0, this.quadVertexBuffer);
passEncoder.setBindGroup(0, this.bindGroup);
passEncoder.draw(4, 1);
passEncoder.end();
}
private ensureBindGroupExists(trailMapIn: GPUTexture) {
if (this.previousTrailMapIn !== trailMapIn) {
this.bindGroup = this.device.createBindGroup({
layout: this.pipeline.getBindGroupLayout(0),
entries: [
{
binding: 0,
resource: {
buffer: this.uniforms,
},
},
{
binding: 1,
resource: this.device.createSampler({
magFilter: 'linear',
minFilter: 'linear',
}),
},
{
binding: 2,
resource: trailMapIn.createView(),
},
],
});
this.previousTrailMapIn = trailMapIn;
}
}
}