- determine if textures are loaded in texture memory
C SPECIFICATION
PARAMETERS
_param1 Specifies the number of textures to be queried.
_param2 Specifies an array containing the names of the
textures to be queried.
_param3 Specifies an array in which the texture residence
status is returned. The residence status of a
texture named by an element of _param2 is
returned in the corresponding element of _param3.
DESCRIPTION
GL establishes a ``working set'' of textures that are res-
ident in texture memory. These textures can be bound to a
texture target much more efficiently than textures that
are not resident.
glAreTexturesResident queries the texture residence status
of the _param1 textures named by the elements of _param2.
If all the named textures are resident,
glAreTexturesResident returns GL_TRUE, and the contents of
_param3 are undisturbed. If not all the named textures
are resident, glAreTexturesResident returns GL_FALSE, and
detailed status is returned in the _param1 elements of
_param3. If an element of _param3 is GL_TRUE, then the
texture named by the corresponding element of _param2 is
resident.
The residence status of a single bound texture may also be
queried by calling glGetTexParameter with the target argu-
ment set to the target to which the texture is bound, and
the pname argument set to GL_TEXTURE_RESIDENT. This is
the only way that the residence status of a default tex-
ture can be queried.
NOTES
glAreTexturesResident is available only if the GL version
is 1.1 or greater.
glAreTexturesResident returns the residency status of the
textures at the time of invocation. It does not guarantee
that the textures will remain resident at any other time.
If textures reside in virtual memory (there is no texture
memory), they are considered always resident.
Some implementations may not load a texture until the
first use of that texture.
glGetTexParameter with parameter name GL_TEXTURE_RESIDENT
retrieves the residence status of a currently bound tex-
ture.
SEE ALSO
glBindTexture, glGetTexParameter, glPrioritizeTextures,
glTexImage1D, glTexImage2D, glTexImage3D, glTexParameter
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