'\"! eqn | mmdoc
'\"macro stdmacro
.ds Vn Version 1.2
.ds Dt 6 March 1997
.ds Re Release 1.1.0
.ds Dp Mar 17 18:04
.ds Dm  Mar  6 20:0
.ds Xs 34038 9 copyteximage2d.gl
.TH GLCOPYTEXIMAGE2D
.SH NAME
.B "glCopyTexImage2D
\- copy pixels into a 2D texture image

.SH C SPECIFICATION
void \f3glCopyTexImage2D\fP(
GLenum \fItarget\fP,
.nf
.ta \w'\f3void \fPglCopyTexImage2D( 'u
	GLint \fIlevel\fP,
	GLenum \fIinternalFormat\fP,
	GLint \fIx\fP,
	GLint \fIy\fP,
	GLsizei \fIwidth\fP,
	GLsizei \fIheight\fP,
	GLint \fIborder\fP )
.fi

.EQ
delim $$
.EN
.SH PARAMETERS
.TP \w'\fIinternalFormat\fP\ \ 'u 
\f2target\fP
Specifies the target texture.
Must be \f3GL_TEXTURE_2D\fP.
.TP
\f2level\fP
Specifies the level-of-detail number.
Level 0 is the base image level.
Level \f2n\fP is the \f2n\fPth mipmap reduction image.
.TP
\f2internalFormat\fP
Specifies the internal format of the texture.
Must be one of the following symbolic constants:
\f3GL_ALPHA\fP,
\f3GL_ALPHA4\fP,
\f3GL_ALPHA8\fP,
\f3GL_ALPHA12\fP,
\f3GL_ALPHA16\fP,
\f3GL_LUMINANCE\fP,
\f3GL_LUMINANCE4\fP,
\f3GL_LUMINANCE8\fP,
\f3GL_LUMINANCE12\fP,
\f3GL_LUMINANCE16\fP,
\f3GL_LUMINANCE_ALPHA\fP,
\f3GL_LUMINANCE4_ALPHA4\fP,
\f3GL_LUMINANCE6_ALPHA2\fP,
\f3GL_LUMINANCE8_ALPHA8\fP,
\f3GL_LUMINANCE12_ALPHA4\fP,
\f3GL_LUMINANCE12_ALPHA12\fP,
\f3GL_LUMINANCE16_ALPHA16\fP,
\f3GL_INTENSITY\fP,
\f3GL_INTENSITY4\fP,
\f3GL_INTENSITY8\fP,
\f3GL_INTENSITY12\fP,
\f3GL_INTENSITY16\fP,
\f3GL_RGB\fP,
\f3GL_R3_G3_B2\fP,
\f3GL_RGB4\fP,
\f3GL_RGB5\fP,
\f3GL_RGB8\fP,
\f3GL_RGB10\fP,
\f3GL_RGB12\fP,
\f3GL_RGB16\fP,
\f3GL_RGBA\fP,
\f3GL_RGBA2\fP,
\f3GL_RGBA4\fP,
\f3GL_RGB5_A1\fP,
\f3GL_RGBA8\fP,
\f3GL_RGB10_A2\fP,
\f3GL_RGBA12\fP, or
\f3GL_RGBA16\fP.
.TP
\f2x\fP, \f2y\fP
Specify the window coordinates of the lower left corner
of the rectangular region of pixels to be copied.
.TP
\f2width\fP
Specifies the width of the texture image.
Must be 0 or $2**n ~+~ 2*$\f2border\fP for some integer $n$.
.TP
\f2height\fP
Specifies the height of the texture image.
Must be 0 or $2**m ~+~ 2*$\f2border\fP for some integer $m$.
.TP
\f2border\fP
Specifies the width of the border.
Must be either 0 or 1.
.SH DESCRIPTION
\f3glCopyTexImage2D\fP defines a two-dimensional texture image with pixels from the current
\f3GL_READ_BUFFER\fP.
.P
The screen-aligned pixel rectangle with lower left corner at (\f2x\fP,
\f2y\fP) and with a width of \f2width\fP$~+~2~*~$\f2border\fP and a height of
\f2height\fP$~+~2~*~$\f2border\fP 
defines the texture array
at the mipmap level specified by \f2level\fP.
\f2internalFormat\fP specifies the internal format of the texture array.
.P
The pixels in the rectangle are processed exactly as if
\f3glCopyPixels\fP had been called, but the process stops just before
final conversion.
At this point all pixel component values are clamped to the range $[0,1]$
and then converted to the texture's internal format for storage in the texel
array.
.P
Pixel ordering is such that lower $x$ and $y$ screen coordinates correspond to 
lower $s$ and $t$ texture coordinates.
.P
If any of the pixels within the specified rectangle of the current
\f3GL_READ_BUFFER\fP are outside the window associated with the current
rendering context, then the values obtained for those pixels are undefined.
.P
.SH NOTES
\f3glCopyTexImage2D\fP is available only if the GL version is 1.1 or greater.
.P
Texturing has no effect in color index mode.
.P
1, 2, 3, and 4 are not accepted values for \f2internalFormat\fP.
.P 
An image with height or width of 0 indicates a NULL texture. 
.SH ERRORS
\f3GL_INVALID_ENUM\fP is generated if \f2target\fP is not \f3GL_TEXTURE_2D\fP.
.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 $log sub 2 max$,
where $max$ is the returned value of \f3GL_MAX_TEXTURE_SIZE\fP.
.P
\f3GL_INVALID_VALUE\fP is generated if \f2width\fP or \f2height\fP is less than 0,
greater than $2~+~$\f3GL_MAX_TEXTURE_SIZE\fP, or if \f2width\fP or \f2height\fP cannot be
represented as $2**k ~+~ 2~*~$\f2border\fP for some integer
$k$.
.P
\f3GL_INVALID_VALUE\fP is generated if \f2border\fP is not 0 or 1.
.P
\f3GL_INVALID_VALUE\fP is generated if \f2internalFormat\fP is not one of the
allowable values.
.P
\f3GL_INVALID_OPERATION\fP is generated if \f3glCopyTexImage2D\fP is executed
between the execution of \f3glBegin\fP and the corresponding
execution of \f3glEnd\fP.
.SH ASSOCIATED GETS
\f3glGetTexImage\fP
.br
\f3glIsEnabled\fP with argument \f3GL_TEXTURE_2D\fP
.SH SEE ALSO
\f3glCopyPixels\fP,
\f3glCopyTexImage1D\fP,
\f3glCopyTexSubImage1D\fP,
\f3glCopyTexSubImage2D\fP,
\f3glPixelStore\fP,
\f3glPixelTransfer\fP,
\f3glTexEnv\fP,
\f3glTexGen\fP,
\f3glTexImage1D\fP,
\f3glTexImage2D\fP,
\f3glTexSubImage1D\fP,
\f3glTexSubImage2D\fP,
.br
\f3glTexParameter\fP