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 theGPUBuffer
in the specified range. mapAsync()
Experimental-
Maps the specified range of the
GPUBuffer
. Returns aPromise
that resolves when theGPUBuffer
's content is ready to be accessed withGPUBuffer.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:
GPUBuffer.mapAsync()
is used to map theGPUBuffer
for reading.GPUBuffer.getMappedRange()
is used to return anArrayBuffer
containing theGPUBuffer
's contents.GPUBuffer.unmap()
is used to unmap theGPUBuffer
again, once we have read the content into JavaScript as needed.
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
- The WebGPU API