WasmGPU.compute.readback.readScalarF32¶
Summary¶
WasmGPU.compute.readback.readScalarF32 reads a single f32 scalar from a GPU source.
It is equivalent to readAs(Float32Array, ..., 4) followed by reading index 0.
Use this for scalar reductions such as sum, min, max, or other single-value outputs.
Source offset is in bytes and should be 4-byte aligned.
Syntax¶
WasmGPU.compute.readback.readScalarF32(src: ReadbackSource, srcOffsetBytes?: number, opts?: { label?: string }): Promise<number>
const value = await wgpu.compute.readback.readScalarF32(src, srcOffsetBytes, opts);
Parameters¶
| Name | Type | Required | Description |
|---|---|---|---|
src |
ReadbackSource |
Yes | Source GPU buffer to read from. |
srcOffsetBytes |
number |
No | Byte offset where the scalar starts (default 0). |
opts |
{ label?: string } |
No | Optional debug label for readback instrumentation. |
Returns¶
Promise<number> - Resolves to the scalar f32 value read from the source buffer.
Example¶
const canvas = document.querySelector("canvas");
const wgpu = await WasmGPU.create(canvas);
const storage = wgpu.compute.createStorageBuffer({ data: new Float32Array([42]), copySrc: true });
const value = await wgpu.compute.readback.readScalarF32(storage);
console.log(value);