The GPUQuerySet interface of the WebGPU API is used to record the results of queries on passes, such as occlusion or timestamp queries.

• Occlusion queries are available on render passes to query whether any fragment samples pass all the per-fragment tests for a set of drawing commands (including scissor, sample mask, alpha to coverage, stencil, and depth tests). To run an occlusion query, an appropriate GPUQuerySet must be provided as the value of the occlusionQuerySet descriptor property when invoking GPUCommandEncoder.beginRenderPass() to run a render pass.
• Timestamp queries allow applications to write timestamps to a GPUQuerySet. To run a timestamp query, appropriate GPUQuerySets must be provided inside the value of the timestampWrites descriptor property when invoking GPUCommandEncoder.beginRenderPass() to run a render pass, or GPUCommandEncoder.beginComputePass() to run a compute pass. Alternatively, you can run a single timestamp query at any time by invoking GPUCommandEncoder.writeTimeStamp() with an appropriate GPUQuerySet as a parameter.

A GPUQuerySet object instance is created using the GPUDevice.createQuerySet() method.

count Experimental Read only

A number specifying the number of queries managed by the GPUQuerySet.

label Experimental

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

type Experimental Read only

An enumerated value specifying the type of queries managed by the GPUQuerySet.

destroy() Experimental

Destroys the GPUQuerySet.

The following snippet creates a GPUQuerySet that holds 32 occlusion query results, and then returns the type and count:

const querySet = device.createQuerySet({
  type: "occlusion",
  count: 32,
});

console.log(querySet.count); // 32
console.log(querySet.type); // "occlusion"

• The WebGPU API