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