The requestDevice()
method of the GPUAdapter
interface returns a Promise
that fulfills with a GPUDevice
object, which is the primary interface for communicating with the GPU.
requestDevice()
requestDevice(descriptor)
-
descriptor
Optional
-
An object containing the following properties:
-
defaultQueue
Optional
-
An object that provides information for the device's default GPUQueue
(as returned by GPUDevice.queue
). This object has a single property — label
— which provides the default queue with a label
value. If no value is provided, this defaults to an empty object, and the default queue's label will be an empty string.
-
label
Optional
-
A string providing a label that can be used to identify the GPUDevice
, for example in GPUError
messages or console warnings.
-
requiredFeatures
Optional
-
An array of strings representing additional functionality that you want supported by the returned GPUDevice
. The requestDevice()
call will fail if the GPUAdapter
cannot provide these features. See GPUSupportedFeatures
for a full list of possible features. This defaults to an empty array if no value is provided.
-
requiredLimits
Optional
-
An object containing properties representing the limits that you want supported by the returned GPUDevice
. The requestDevice()
call will fail if the GPUAdapter
cannot provide these limits. Each key must be the name of a member of GPUSupportedLimits
. This defaults to an empty object if no value is provided.
Note: Not all features and limits will be available to WebGPU in all browsers that support it, even if they are supported by the underlying hardware. See the features
and limits
pages for more information.
A Promise
that fulfills with a GPUDevice
object instance.
If you make a duplicate call, i.e. call requestDevice()
on a GPUAdapter
that requestDevice()
was already called on, the promise fulfills with a device that is immediately lost. You can then get information on how the device was lost via GPUDevice.lost
.
async function init() {
if (!navigator.gpu) {
throw Error("WebGPU not supported.");
}
const adapter = await navigator.gpu.requestAdapter();
if (!adapter) {
throw Error("Couldn't request WebGPU adapter.");
}
const device = await adapter.requestDevice();
}
In the following code we:
- Check whether a
GPUAdapter
has the texture-compression-astc
feature available. If so, we push it into the array of requiredFeatures
. - Query the
GPUAdapter.limits
value of maxBindGroups
to see if it is equal to or greater than 6. Our theoretical example app ideally needs 6 bind groups, so if the returned value is >= 6, we add a maximum limit of 6 to the requiredLimits
object. - Request a device with those feature and limit requirements, plus a
defaultQueue
label.
async function init() {
if (!navigator.gpu) {
throw Error("WebGPU not supported.");
}
const adapter = await navigator.gpu.requestAdapter();
if (!adapter) {
throw Error("Couldn't request WebGPU adapter.");
}
const requiredFeatures = [];
if (adapter.features.has("texture-compression-astc")) {
requiredFeatures.push("texture-compression-astc");
}
const requiredLimits = {};
if (adapter.limits.maxBindGroups >= 6) {
requiredLimits.maxBindGroups = 6;
}
const device = await adapter.requestDevice({
defaultQueue: {
label: "myqueue",
},
requiredFeatures,
requiredLimits,
});
}