HP c3700 - Workstation, Reference Manual, Page: 15 / 486

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glAreaTexturesResident
Chapter 1
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glAreaTexturesResident
glAreaTexturesResident
: 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.