GPUBuffer

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The GPUBuffer interface of the WebGPU API represents a block of memory that can be used to store raw data to use in GPU operations.

A GPUBuffer object instance is created using the GPUDevice.createBuffer() method.

Instance properties

label Experimental

A string providing a label that can be used to identify the object, for example in GPUError messages or console warnings.

mapState Experimental Read only

An enumerated value representing the mapped state of the GPUBuffer.

size Experimental Read only

A number representing the length of the GPUBuffer's memory allocation, in bytes.

usage Experimental Read only

The bitwise flags representing the allowed usages of the GPUBuffer.

Instance methods

destroy() Experimental

Destroys the GPUBuffer.

getMappedRange() Experimental

Returns an ArrayBuffer containing the mapped contents of the GPUBuffer in the specified range.

mapAsync() Experimental

Maps the specified range of the GPUBuffer. Returns a Promise that resolves when the GPUBuffer's content is ready to be accessed with GPUBuffer.getMappedRange().

unmap() Experimental

Unmaps the mapped range of the GPUBuffer, making its contents available for use by the GPU again.

Examples

In our basic compute demo, we create an output buffer to read GPU calculations to, and a staging buffer to be mapped for JavaScript access.

js

const output = device.createBuffer({
  size: BUFFER_SIZE,
  usage: GPUBufferUsage.STORAGE | GPUBufferUsage.COPY_SRC,
});

const stagingBuffer = device.createBuffer({
  size: BUFFER_SIZE,
  usage: GPUBufferUsage.MAP_READ | GPUBufferUsage.COPY_DST,
});

Later on, once the stagingBuffer contains the results of the GPU computation, a combination of GPUBuffer methods are used to read the data back to JavaScript so that it can then be logged to the console:

js

// map staging buffer to read results back to JS
await stagingBuffer.mapAsync(
  GPUMapMode.READ,
  0, // Offset
  BUFFER_SIZE // Length
);

const copyArrayBuffer = stagingBuffer.getMappedRange(0, BUFFER_SIZE);
const data = copyArrayBuffer.slice();
stagingBuffer.unmap();
console.log(new Float32Array(data));

Specifications

Specification
WebGPU
# gpubuffer

Browser compatibility

BCD tables only load in the browser

See also