Skip to content

WasmGPU.compute.readback.readF32

Summary

WasmGPU.compute.readback.readF32 reads f32 elements from a GPU source and returns a Float32Array. Offsets and counts are specified in elements, not bytes. Internally this maps to byte offsets (elemOffset * 4) and byte lengths (elemCount * 4). Use this for common float-result readback after compute dispatches.

Syntax

WasmGPU.compute.readback.readF32(src: ReadbackSource, elemOffset?: number, elemCount?: number, opts?: { label?: string }): Promise<Float32Array>
const out = await wgpu.compute.readback.readF32(src, elemOffset, elemCount, opts);

Parameters

Name Type Required Description
src ReadbackSource Yes Source GPU buffer to read from.
elemOffset number No Element offset within the source (default 0).
elemCount number No Number of f32 elements to read (default reads remaining elements).
opts { label?: string } No Optional debug label for copy instrumentation.

Returns

Promise<Float32Array> - Resolves to float data read from GPU memory.

Example

const canvas = document.querySelector("canvas");
const wgpu = await WasmGPU.create(canvas);

const storage = wgpu.compute.createStorageBuffer({ data: new Float32Array([5, 10, 15, 20]), copySrc: true });
const out = await wgpu.compute.readback.readF32(storage, 1, 2);

console.log(Array.from(out));

See Also