1 files changed, 61 insertions, 0 deletions
diff --git a/dom/webgpu/tests/cts/checkout/src/webgpu/util/texture.ts b/dom/webgpu/tests/cts/checkout/src/webgpu/util/texture.ts
new file mode 100644
index 0000000000..d26508878f
--- /dev/null
+++ b/dom/webgpu/tests/cts/checkout/src/webgpu/util/texture.ts
@@ -0,0 +1,61 @@
+import { assert } from '../../common/util/util.js';
+import { kTextureFormatInfo } from '../capability_info.js';
+
+import { align } from './math.js';
+import { TexelView } from './texture/texel_view.js';
+import { reifyExtent3D } from './unions.js';
+
+/**
+ * Creates a texture with the contents of a TexelView.
+ */
+export function makeTextureWithContents(
+  device: GPUDevice,
+  texelView: TexelView,
+  desc: Omit<GPUTextureDescriptor, 'format'>
+): GPUTexture {
+  const { width, height, depthOrArrayLayers } = reifyExtent3D(desc.size);
+
+  const { bytesPerBlock, blockWidth } = kTextureFormatInfo[texelView.format];
+  // Currently unimplemented for compressed textures.
+  assert(blockWidth === 1);
+
+  // Compute bytes per row.
+  const bytesPerRow = align(bytesPerBlock * width, 256);
+
+  // Create a staging buffer to upload the texture contents.
+  const stagingBuffer = device.createBuffer({
+    mappedAtCreation: true,
+    size: bytesPerRow * height * depthOrArrayLayers,
+    usage: GPUBufferUsage.COPY_SRC,
+  });
+
+  // Write the texels into the staging buffer.
+  texelView.writeTextureData(new Uint8Array(stagingBuffer.getMappedRange()), {
+    bytesPerRow,
+    rowsPerImage: height,
+    subrectOrigin: [0, 0, 0],
+    subrectSize: [width, height, depthOrArrayLayers],
+  });
+  stagingBuffer.unmap();
+
+  // Create the texture.
+  const texture = device.createTexture({
+    ...desc,
+    format: texelView.format,
+    usage: desc.usage | GPUTextureUsage.COPY_DST,
+  });
+
+  // Copy from the staging buffer into the texture.
+  const commandEncoder = device.createCommandEncoder();
+  commandEncoder.copyBufferToTexture(
+    { buffer: stagingBuffer, bytesPerRow },
+    { texture },
+    desc.size
+  );
+  device.queue.submit([commandEncoder.finish()]);
+
+  // Clean up the staging buffer.
+  stagingBuffer.destroy();
+
+  return texture;
+}