2010 Khronos Group.
glBeginQueryIndexed, glEndQueryIndexed 3G
glBeginQueryIndexed, glEndQueryIndexed delimit the boundaries of a query object on an indexed target

## C Specification

void `glBeginQueryIndexed` GLenum target GLuint index GLuint id

## Parameters

target

  Specifies the target type of query object established between `glBeginQueryIndexed` and the subsequent glEndQueryIndexed. The symbolic constant must be one of `GL_SAMPLES_PASSED`, `GL_ANY_SAMPLES_PASSED`, `GL_PRIMITIVES_GENERATED`, `GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN`, or `GL_TIME_ELAPSED`.

index

  Specifies the index of the query target upon which to begin the query.

id

  Specifies the name of a query object.

## C Specification

void `glEndQueryIndexed` GLenum target GLuint index

## Parameters

target

  Specifies the target type of query object to be concluded. The symbolic constant must be one of `GL_SAMPLES_PASSED`, `GL_ANY_SAMPLES_PASSED`, `GL_PRIMITIVES_GENERATED`, `GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN`, or `GL_TIME_ELAPSED`.

index

  Specifies the index of the query target upon which to end the query.

## Description

`glBeginQueryIndexed` and glEndQueryIndexed delimit the boundaries of a query object. query must be a name previously returned from a call to glGenQueries. If a query object with name id does not yet exist it is created with the type determined by target. target must be one of `GL_SAMPLES_PASSED`, `GL_ANY_SAMPLES_PASSED`, `GL_PRIMITIVES_GENERATED`, `GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN`, or `GL_TIME_ELAPSED`. The behavior of the query object depends on its type and is as follows.

index specifies the index of the query target and must be between a target-specific maximum.

If target is `GL_SAMPLES_PASSED`, id must be an unused name, or the name of an existing occlusion query object. When `glBeginQueryIndexed` is executed, the query object's samples-passed counter is reset to 0. Subsequent rendering will increment the counter for every sample that passes the depth test. If the value of `GL_SAMPLE_BUFFERS` is 0, then the samples-passed count is incremented by 1 for each fragment. If the value of `GL_SAMPLE_BUFFERS` is 1, then the samples-passed count is incremented by the number of samples whose coverage bit is set. However, implementations, at their discression may instead increase the samples-passed count by the value of `GL_SAMPLES` if any sample in the fragment is covered. When `glEndQueryIndexed` is executed, the samples-passed counter is assigned to the query object's result value. This value can be queried by calling glGetQueryObject with pname `GL_QUERY_RESULT`. When target is `GL_SAMPLES_PASSED`, index must be zero.

If target is `GL_ANY_SAMPLES_PASSED`, id must be an unused name, or the name of an existing boolean occlusion query object. When `glBeginQueryIndexed` is executed, the query object's samples-passed flag is reset to `GL_FALSE`. Subsequent rendering causes the flag to be set to `GL_TRUE` if any sample passes the depth test. When `glEndQueryIndexed` is executed, the samples-passed flag is assigned to the query object's result value. This value can be queried by calling glGetQueryObject with pname `GL_QUERY_RESULT`. When target is `GL_ANY_SAMPLES_PASSED`, index must be zero.

If target is `GL_PRIMITIVES_GENERATED`, id must be an unused name, or the name of an existing primitive query object previously bound to the `GL_PRIMITIVES_GENERATED` query binding. When `glBeginQueryIndexed` is executed, the query object's primitives-generated counter is reset to 0. Subsequent rendering will increment the counter once for every vertex that is emitted from the geometry shader to the stream given by index, or from the vertex shader if index is zero and no geometry shader is present. When `glEndQueryIndexed` is executed, the primitives-generated counter for stream index is assigned to the query object's result value. This value can be queried by calling glGetQueryObject with pname `GL_QUERY_RESULT`. When target is `GL_PRIMITIVES_GENERATED`, index must be less than the value of `GL_MAX_VERTEX_STREAMS`.

If target is `GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN`, id must be an unused name, or the name of an existing primitive query object previously bound to the `GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN` query binding. When `glBeginQueryIndexed` is executed, the query object's primitives-written counter for the stream specified by index is reset to 0. Subsequent rendering will increment the counter once for every vertex that is written into the bound transform feedback buffer(s) for stream index. If transform feedback mode is not activated between the call to `glBeginQueryIndexed` and `glEndQueryIndexed`, the counter will not be incremented. When `glEndQueryIndexed` is executed, the primitives-written counter for stream index is assigned to the query object's result value. This value can be queried by calling glGetQueryObject with pname `GL_QUERY_RESULT`. When target is `GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN`, index must be less than the value of `GL_MAX_VERTEX_STREAMS`.

If target is `GL_TIME_ELAPSED`, id must be an unused name, or the name of an existing timer query object previously bound to the `GL_TIME_ELAPSED` query binding. When `glBeginQueryIndexed` is executed, the query object's time counter is reset to 0. When `glEndQueryIndexed` is executed, the elapsed server time that has passed since the call to `glBeginQueryIndexed` is written into the query object's time counter. This value can be queried by calling glGetQueryObject with pname `GL_QUERY_RESULT`. When target is `GL_TIME_ELAPSED`, index must be zero.

Querying the `GL_QUERY_RESULT` implicitly flushes the GL pipeline until the rendering delimited by the query object has completed and the result is available. `GL_QUERY_RESULT_AVAILABLE` can be queried to determine if the result is immediately available or if the rendering is not yet complete.

## Notes

If the query target's count exceeds the maximum value representable in the number of available bits, as reported by glGetQueryiv with target set to the appropriate query target and pname `GL_QUERY_COUNTER_BITS`, the count becomes undefined.

An implementation may support 0 bits in its counter, in which case query results are always undefined and essentially useless.

When `GL_SAMPLE_BUFFERS` is 0, the samples-passed counter of an occlusion query will increment once for each fragment that passes the depth test. When `GL_SAMPLE_BUFFERS` is 1, an implementation may either increment the samples-passed counter individually for each sample of a fragment that passes the depth test, or it may choose to increment the counter for all samples of a fragment if any one of them passes the depth test.

Calling glBeginQuery or glEndQuery is equivalent to calling glBeginQueryIndexed or glEndQueryIndexed with index set to zero, respectively.

## Errors

`GL_INVALID_ENUM` is generated if target is not one of the accepted tokens.

`GL_INVALID_VALUE` is generated if index is greater than the query target-specific maximum.

`GL_INVALID_OPERATION` is generated if `glBeginQueryIndexed` is executed while a query object of the same target is already active.

`GL_INVALID_OPERATION` is generated if glEndQueryIndexed is executed when a query object of the same target is not active.

`GL_INVALID_OPERATION` is generated if id is 0.

`GL_INVALID_OPERATION` is generated if id is the name of an already active query object.

`GL_INVALID_OPERATION` is generated if id refers to an existing query object whose type does not does not match target.

## See Also

glDeleteQueries, glBeginQuery, glEndQuery, glGenQueries, glGetQueryiv, glGetQueryObject, glIsQuery

## Copyright

Copyright 2010 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. http://opencontent.org/openpub/.