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import { assert, unreachable } from '../../../common/util/util.js';
import { runRefTest } from './gpu_ref_test.js';
type WriteCanvasMethod = 'draw' | 'copy';
export function run(
format: GPUTextureFormat,
alphaMode: GPUCanvasAlphaMode,
writeCanvasMethod: WriteCanvasMethod
) {
runRefTest(async t => {
const module = t.device.createShaderModule({
code: `
struct VertexOutput {
@builtin(position) Position : vec4<f32>,
@location(0) fragColor : vec4<f32>,
}
@vertex
fn mainVS(@builtin(vertex_index) VertexIndex : u32) -> VertexOutput {
var pos = array<vec2<f32>, 6>(
vec2<f32>( 0.75, 0.75),
vec2<f32>( 0.75, -0.75),
vec2<f32>(-0.75, -0.75),
vec2<f32>( 0.75, 0.75),
vec2<f32>(-0.75, -0.75),
vec2<f32>(-0.75, 0.75));
var offset = array<vec2<f32>, 4>(
vec2<f32>( -0.25, 0.25),
vec2<f32>( 0.25, 0.25),
vec2<f32>(-0.25, -0.25),
vec2<f32>( 0.25, -0.25));
// Alpha channel value is set to 0.5 regardless of the canvas alpha mode.
// For 'opaque' mode, it shouldn't affect the end result, as the alpha channel should always get cleared to 1.0.
var color = array<vec4<f32>, 4>(
vec4<f32>(0.4, 0.0, 0.0, 0.5),
vec4<f32>(0.0, 0.4, 0.0, 0.5),
vec4<f32>(0.0, 0.0, 0.4, 0.5),
vec4<f32>(0.4, 0.4, 0.0, 0.5)); // 0.4 -> 0x66
var output : VertexOutput;
output.Position = vec4<f32>(pos[VertexIndex % 6u] + offset[VertexIndex / 6u], 0.0, 1.0);
output.fragColor = color[VertexIndex / 6u];
return output;
}
@fragment
fn mainFS(@location(0) fragColor: vec4<f32>) -> @location(0) vec4<f32> {
return fragColor;
}
`,
});
document.querySelectorAll('canvas').forEach(canvas => {
const ctx = canvas.getContext('webgpu');
assert(ctx instanceof GPUCanvasContext, 'Failed to get WebGPU context from canvas');
switch (format) {
case 'bgra8unorm':
case 'bgra8unorm-srgb':
case 'rgba8unorm':
case 'rgba8unorm-srgb':
case 'rgba16float':
break;
default:
unreachable();
}
let usage = 0;
switch (writeCanvasMethod) {
case 'draw':
usage = GPUTextureUsage.RENDER_ATTACHMENT;
break;
case 'copy':
usage = GPUTextureUsage.COPY_DST;
break;
}
ctx.configure({
device: t.device,
format,
usage,
alphaMode,
});
// The blending behavior here is to mimic 2d context blending behavior
// of drawing rects in order
// https://drafts.fxtf.org/compositing/#porterduffcompositingoperators_srcover
const kBlendStateSourceOver = {
color: {
srcFactor: 'src-alpha',
dstFactor: 'one-minus-src-alpha',
operation: 'add',
},
alpha: {
srcFactor: 'one',
dstFactor: 'one-minus-src-alpha',
operation: 'add',
},
} as const;
const pipeline = t.device.createRenderPipeline({
layout: 'auto',
vertex: {
module,
entryPoint: 'mainVS',
},
fragment: {
module,
entryPoint: 'mainFS',
targets: [
{
format,
blend: { premultiplied: kBlendStateSourceOver, opaque: undefined }[alphaMode],
},
],
},
primitive: {
topology: 'triangle-list',
},
});
let renderTarget: GPUTexture;
switch (writeCanvasMethod) {
case 'draw':
renderTarget = ctx.getCurrentTexture();
break;
case 'copy':
renderTarget = t.device.createTexture({
size: [ctx.canvas.width, ctx.canvas.height],
format,
usage: GPUTextureUsage.RENDER_ATTACHMENT | GPUTextureUsage.COPY_SRC,
});
break;
}
const renderPassDescriptor: GPURenderPassDescriptor = {
colorAttachments: [
{
view: renderTarget.createView(),
clearValue: { r: 0.0, g: 0.0, b: 0.0, a: 0.0 },
loadOp: 'clear',
storeOp: 'store',
},
],
};
const commandEncoder = t.device.createCommandEncoder();
const passEncoder = commandEncoder.beginRenderPass(renderPassDescriptor);
passEncoder.setPipeline(pipeline);
passEncoder.draw(6, 1, 0, 0);
passEncoder.draw(6, 1, 6, 0);
passEncoder.draw(6, 1, 12, 0);
passEncoder.draw(6, 1, 18, 0);
passEncoder.end();
switch (writeCanvasMethod) {
case 'draw':
break;
case 'copy':
commandEncoder.copyTextureToTexture(
{
texture: renderTarget,
},
{
texture: ctx.getCurrentTexture(),
},
[ctx.canvas.width, ctx.canvas.height]
);
break;
}
t.device.queue.submit([commandEncoder.finish()]);
});
});
}
|
