glAreTexturesResident(3G) OpenGL Reference glAreTexturesResident(3G)
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 GLTRUE, and the contents of
residences are undisturbed. If not all the named textures are resident,
glAreTexturesResident returns GLFALSE, and detailed status is returned
in the n elements of residences. If an element of residences is GLTRUE,
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
GLTEXTURERESIDENT. 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.
Page 1
glAreTexturesResident(3G) OpenGL Reference glAreTexturesResident(3G)
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
GLINVALIDVALUE is generated if n is negative.
GLINVALIDVALUE is generated if any element in textures is 0 or does not
name a texture. In that case, the function returns GLFALSE and the
contents of residences is indeterminate.
GLINVALIDOPERATION is generated if glAreTexturesResident is executed
between the execution of glBegin and the corresponding execution of
glEnd.
ASSOCIATED GETS
glGetTexParameter with parameter name GLTEXTURERESIDENT retrieves the
residence status of a currently bound texture.
SEE ALSO
glBindTexture, glGetTexParameter, glPrioritizeTextures, glTexImage1D,
glTexImage2D, glTexParameter
Page 2