NAME
glAreTexturesResident - determine if textures are loaded in
texture memory
C SPECIFICATION
GLboolean glAreTexturesResident( GLsizei n,
const GLuint *textures,
GLboolean *residences )
PARAMETERS
n Specifies the number of textures to be queried.
textures Specifies an array containing the names of the
textures to be queried.
residences Specifies an array in which the texture
residence status is returned. The residence
status of a texture named by an element of
textures is returned in the corresponding
element of residences.
DESCRIPTION
GL establishes a ``working set'' of textures that are
resident 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 n textures named by the elements of textures. If all
the named textures are resident, glAreTexturesResident
returns GL_TRUE, and the contents of residences are
undisturbed. If not all the named textures are resident,
glAreTexturesResident returns GL_FALSE, and detailed status
is returned in the n elements of residences. If an element
of residences is GL_TRUE, then the texture named by the
corresponding element of textures is resident.
The residence status of a single bound texture may also be
queried by calling glGetTexParameter with the target
argument set to the target to which the texture is bound,
and the p_name argument set to GL_TEXTURE_RESIDENT. This is
the only way that the residence status of a default texture
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.
ERRORS
GL_INVALID_VALUE is generated if n is negative.
GL_INVALID_VALUE is generated if any element in textures is
0 or does not name a texture. In that case, the function
returns GL_FALSE and the contents of residences is
indeterminate.
GL_INVALID_OPERATION is generated if glAreTexturesResident
is executed between the execution of glBegin and the
corresponding execution of glEnd.
ASSOCIATED GETS
glGetTexParameter with parameter name GL_TEXTURE_RESIDENT
retrieves the residence status of a currently bound texture.
SEE ALSO
glBindTexture, glGetTexParameter, glPrioritizeTextures,
glTexImage1D, glTexImage2D, glTexParameter