'\"! eqn | mmdoc
'\"macro stdmacro
.ds Vn Version 1.2
.ds Dt 6 March 1997
.ds Re Release 1.1.0
.ds Dp Mar 17 18:06
.ds Dm  Mar  6 20:0
.ds Xs 37493 9 gettexlevelparameter.gl
.TH GLGETTEXLEVELPARAMETER
.SH NAME
.B "glGetTexLevelParameterfv, glGetTexLevelParameteriv
\- return texture parameter values for a specific level of detail

.SH C SPECIFICATION
void \f3glGetTexLevelParameterfv\fP(
GLenum \fItarget\fP,
.nf
.ta \w'\f3void \fPglGetTexLevelParameterfv( 'u
	GLint \fIlevel\fP,
	GLenum \fIpname\fP,
	GLfloat \fI*params\fP )
.fi
void \f3glGetTexLevelParameteriv\fP(
GLenum \fItarget\fP,
.nf
.ta \w'\f3void \fPglGetTexLevelParameteriv( 'u
	GLint \fIlevel\fP,
	GLenum \fIpname\fP,
	GLint \fI*params\fP )
.fi

.EQ
delim $$
.EN
.SH PARAMETERS
.TP \w'\f2target\fP\ \ 'u 
\f2target\fP
Specifies the symbolic name of the target texture,
either \f3GL_TEXTURE_1D\fP, \f3GL_TEXTURE_2D\fP, 
\f3GL_PROXY_TEXTURE_1D\fP, or \f3GL_PROXY_TEXTURE_2D\fP.
.TP
\f2level\fP
Specifies the level-of-detail number of the desired image.
Level 0 is the base image level.
Level $n$ is the $n$th mipmap reduction image.
.TP
\f2pname\fP
Specifies the symbolic name of a texture parameter.
\f3GL_TEXTURE_WIDTH\fP,
\f3GL_TEXTURE_HEIGHT\fP,
\f3GL_TEXTURE_INTERNAL_FORMAT\fP,
\f3GL_TEXTURE_BORDER\fP,
\f3GL_TEXTURE_RED_SIZE\fP,
\f3GL_TEXTURE_GREEN_SIZE\fP,
\f3GL_TEXTURE_BLUE_SIZE\fP,
\f3GL_TEXTURE_ALPHA_SIZE\fP,
\f3GL_TEXTURE_LUMINANCE_SIZE\fP, and
\f3GL_TEXTURE_INTENSITY_SIZE\fP are accepted.
.TP
\f2params\fP
Returns the requested data.
.SH DESCRIPTION
\f3glGetTexLevelParameter\fP returns in \f2params\fP texture parameter values for a specific 
level-of-detail value,
specified as \f2level\fP.
\f2target\fP defines the target texture,
either \f3GL_TEXTURE_1D\fP, \f3GL_TEXTURE_2D\fP,
\f3GL_PROXY_TEXTURE_1D\fP, or 
\f3GL_PROXY_TEXTURE_2D\fP.
.BR
.P
\f3GL_MAX_TEXTURE_SIZE\fP is not really descriptive enough.
It has to report the largest square texture image that can be
accommodated with mipmaps and borders, 
but a long skinny texture, or a texture without mipmaps and borders, may
easily fit in texture memory. 
The proxy targets allow the user to more accurately query
whether the GL can accommodate a texture of a given configuration.
If the texture cannot be accommodated, the texture state variables, which
may be queried with \f3glGetTexLevelParameter\fP, are set to 0.  If the texture can be accommodated,
the texture state values will be set as they would be set for a
non-proxy target.
.P
\f2pname\fP specifies the texture parameter whose value or values
will be returned.
.P
The accepted parameter names are as follows:
.TP 10
\f3GL_TEXTURE_WIDTH\fP
\f2params\fP returns a single value,
the width of the texture image.
This value includes the border of the texture image. The initial value is
0. 
.TP
\f3GL_TEXTURE_HEIGHT\fP
\f2params\fP returns a single value,
the height of the texture image.
This value includes the border of the texture image. The initial value is
0. 
.TP
\f3GL_TEXTURE_INTERNAL_FORMAT\fP
\f2params\fP returns a single value,
the internal format of the texture image. 
.TP
\f3GL_TEXTURE_BORDER\fP
\f2params\fP returns a single value,
the width in pixels of the border of the texture image. The initial value
is 0. 
.TP
\f3GL_TEXTURE_RED_SIZE\fP,
.TP
\f3GL_TEXTURE_GREEN_SIZE\fP,
.TP
\f3GL_TEXTURE_BLUE_SIZE\fP,
.TP
\f3GL_TEXTURE_ALPHA_SIZE\fP,
.TP
\f3GL_TEXTURE_LUMINANCE_SIZE\fP, 
.TP
\f3GL_TEXTURE_INTENSITY_SIZE\fP
The internal storage resolution of an individual component.
The resolution chosen by the GL will be a close match for the resolution
requested by the user with the component argument of \f3glTexImage1D\fP or
\f3glTexImage2D\fP. The initial value is 0. 
.SH NOTES
If an error is generated,
no change is made to the contents of \f2params\fP.
.P
\f3GL_TEXTURE_INTERNAL_FORMAT\fP is only available if the GL version is
1.1 or greater. In version 1.0, use \f3GL_TEXTURE_COMPONENTS\fP
instead.
.P
\f3GL_PROXY_TEXTURE_1D\fP and \f3GL_PROXY_TEXTURE_2D\fP are only
available if the GL version is 1.1 or greater.
.SH ERRORS
\f3GL_INVALID_ENUM\fP is generated if \f2target\fP or \f2pname\fP is not an
accepted value.
.P
\f3GL_INVALID_VALUE\fP is generated if \f2level\fP is less than 0.
.P 
\f3GL_INVALID_VALUE\fP may be generated if \f2level\fP is greater
than $ log sub 2$ \f2max\fP,
where \f2max\fP is the returned value of \f3GL_MAX_TEXTURE_SIZE\fP.
.P
\f3GL_INVALID_OPERATION\fP is generated if \f3glGetTexLevelParameter\fP
is executed between the execution of \f3glBegin\fP
and the corresponding execution of \f3glEnd\fP.
.SH SEE ALSO
\f3glGetTexParameter\fP,
\f3glCopyTexImage1D\fP,
\f3glCopyTexImage2D\fP,
\f3glCopyTexSubImage1D\fP,
\f3glCopyTexSubImage2D\fP,
\f3glTexEnv\fP,
\f3glTexGen\fP,
\f3glTexImage1D\fP,
\f3glTexImage2D\fP,
\f3glTexSubImage1D\fP,
\f3glTexSubImage2D\fP,
.br
\f3glTexParameter\fP