glGetQueryObjectuiv — return parameters of a query object
void glGetQueryObjectuiv( | GLuint id, |
GLenum pname, | |
GLuint * params) ; |
id
Specifies the name of a query object.
pname
Specifies the symbolic name of a query object parameter. Accepted values are GL_QUERY_RESULT
or GL_QUERY_RESULT_AVAILABLE
.
params
Returns the requested data.
glGetQueryObjectuiv
returns in params
a selected parameter of the query object specified by id
.
pname
names a specific query object parameter. pname
can be as follows:
GL_QUERY_RESULT
params
returns the value of the query object's passed samples counter. The initial value is 0.
GL_QUERY_RESULT_AVAILABLE
params
returns whether the passed samples counter is immediately available. If a delay would occur waiting for the query result, GL_FALSE
is returned. Otherwise, GL_TRUE
is returned, which also indicates that the results of all previous queries of the same type are available as well.
If an error is generated, no change is made to the contents of params
.
When pname
is GL_QUERY_RESULT
, glGetQueryObjectuiv
implicitly flushes the GL pipeline so that any incomplete rendering delimited by the occlusion query completes in finite time.
Repeatedly querying the GL_QUERY_RESULT_AVAILABLE
state for any given query object is guaranteed to return true eventually. Note that multiple queries to the same occlusion object may result in a significant performance loss. For better performance it is recommended to wait N frames before querying this state. N is implementation-dependent but is generally between one and three.
If multiple queries are issued using the same query object id
before calling glGetQueryObjectuiv
, the results of the most recent query will be returned. In this case, when issuing a new query, the results of the previous query are discarded.
GL_INVALID_ENUM
is generated if pname
is not an accepted value.
GL_INVALID_OPERATION
is generated if id
is not the name of a query object.
GL_INVALID_OPERATION
is generated if id
is the name of a currently active query object.
OpenGL ES API Version | |||
---|---|---|---|
Function Name | 2.0 | 3.0 | 3.1 |
glGetQueryObjectuiv | - | ✔ | ✔ |
Copyright © 2005 Addison-Wesley. Copyright © 2010-2014 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. https://opencontent.org/openpub/.