GPUCommandEncoder: resolveQuerySet() method

The resolveQuerySet() method of the GPUCommandEncoder interface encodes a command that resolves a GPUQuerySet, copying the results into a specified GPUBuffer.

Syntax

resolveQuerySet(querySet, firstQuery, queryCount, destination, destinationOffset)

Parameters

querySet

A GPUQuerySet object representing the query set to be resolved.

firstQuery

The index number of the first query value to be copied over to the buffer.

queryCount

The number of queries to be copied over to the buffer, starting from firstQuery.

destination

A GPUBuffer representing the buffer to copy the query values to.

destinationOffset

A number representing the offset, in bytes, from the start of the buffer to start writing the query values at.

Return value

None (Undefined).

Validation

The following criteria must be met when calling resolveQuerySet(), otherwise a GPUValidationError is generated and the GPUCommandEncoder becomes invalid:

• The destination.buffer's GPUBuffer.usage includes the GPUBufferUsage.QUERY_RESOLVE flag.
• firstQuery is smaller than the number of queries in querySet.
• firstQuery + queryCount is smaller than or equal to the number of queries in querySet.
• destinationOffset is a multiple of 256.
• destinationOffset + 8 × queryCount is less than or equal to destination.size.

Examples

// …

const queryBuffer = device.createBuffer({
  size: 1024,
  usage: GPUBufferUsage.QUERY_RESOLVE,
});

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

// …

const commandEncoder = device.createCommandEncoder();

// Write timestamps to querySet
commandEncoder.writeTimestamp(querySet, 0);
// …
commandEncoder.writeTimestamp(querySet, 1);
// etc.

// …

commandEncoder.resolveQuerySet(
  querySet,
  0, // First query to write
  16, // Number of queries to count
  queryBuffer,
  0, // Buffer offset
);

// …

Specifications

Browser compatibility

See also

• The WebGPU API