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Table of Contents
glCopyTexImage2D - copy pixels into a 2D texture image
void
glCopyTexImage2D( GLenum target,
GLint level,
GLenum internalformat,
GLint x,
GLint y,
GLsizei width,
GLsizei height,
GLint border )
eqn not supported
- target
- Specifies the target texture. Must be
GL_TEXTURE_2D.
- level
- Specifies the level-of-detail number. Level 0 is the base
image level. Level n is the nth mipmap reduction image.
- internalformat
- Specifies
the internal of the texture. Must be one of the following symbolic constants:
GL_ALPHA, GL_ALPHA4, GL_ALPHA8, GL_ALPHA12, GL_ALPHA16, GL_LUMINANCE, GL_LUMINANCE4,
GL_LUMINANCE8, GL_LUMINANCE12, GL_LUMINANCE16, GL_LUMINANCE_ALPHA, GL_LUMINANCE4_ALPHA4,
GL_LUMINANCE6_ALPHA2, GL_LUMINANCE8_ALPHA8, GL_LUMINANCE12_ALPHA4, GL_LUMINANCE12_ALPHA12,
GL_LUMINANCE16_ALPHA16, GL_INTENSITY, GL_INTENSITY4, GL_INTENSITY8, GL_INTENSITY12,
GL_INTENSITY16, GL_RGB, GL_R3_G3_B2, GL_RGB4, GL_RGB5, GL_RGB8, GL_RGB10,
GL_RGB12, GL_RGB16, GL_RGBA, GL_RGBA2, GL_RGBA4, GL_RGB5_A1, GL_RGBA8,
GL_RGB10_A2, GL_RGBA12, or GL_RGBA16.
- x, y
- Specify the window coordinates
of the lower left corner of the rectangular region of pixels to be copied.
- width
- Specifies the width of the texture image. Must be 0 or $2 sup n ~+~
2*$border for some integer $n$.
- height
- Specifies the height of the texture
image. Must be 0 or $2 sup m ~+~ 2*$border for some integer $m$.
- border
- Specifies
the width of the border. Must be either 0 or 1.
glCopyTexImage2D
defines a two-dimensional texture image with pixels from the current GL_READ_BUFFER.
The screen-aligned pixel rectangle with lower left corner at (x, y) and
with a width of width$~+~2~*~$border and a height of height$~+~2~*~$border
defines the texture array at the mipmap level specified by level. internalformat
specifies the internal of the texture array.
The pixels in the rectangle
are processed exactly as if glCopyPixels 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
for storage in the texel array.
Pixel ordering is such that lower $x$ and
$y$ screen coordinates correspond to lower $s$ and $t$ texture coordinates.
If any of the pixels within the specified rectangle of the current GL_READ_BUFFER
are outside the window associated with the current rendering context, then
the values obtained for those pixels are undefined.
glCopyTexImage2D
is available only if the GL version is 1.1 or greater.
Texturing has no effect
in color index mode.
1, 2, 3, and 4 are not accepted values for internalformat.
An image with height or width of 0 indicates a NULL texture.
When the GL_ARB_imaging
extension is supported, the RGBA components read from the framebuffer may
be processed by the imaging pipeline. See glTexImage1D for specific details.
GL_INVALID_ENUM is generated if target is not GL_TEXTURE_2D.
GL_INVALID_VALUE
is generated if level is less than 0.
GL_INVALID_VALUE may be generated
if level is greater than $log sub 2 max$, where $max$ is the returned value
of GL_MAX_TEXTURE_SIZE.
GL_INVALID_VALUE is generated if width or height
is less than 0, greater than $2~+~$GL_MAX_TEXTURE_SIZE, or if width or
height cannot be represented as $2 sup k ~+~ 2~*~$border for some integer
$k$.
GL_INVALID_VALUE is generated if border is not 0 or 1.
GL_INVALID_VALUE
is generated if internalformat is not one of the allowable values.
GL_INVALID_OPERATION
is generated if glCopyTexImage2D is executed between the execution of glBegin
and the corresponding execution of glEnd.
glGetTexImage
glIsEnabled with argument GL_TEXTURE_2D
glCopyPixels(3G)
, glCopyTexImage1D(3G)
,
glCopyTexSubImage1D(3G)
, glCopyTexSubImage2D(3G)
, glPixelStore(3G)
, glPixelTransfer(3G)
,
glTexEnv(3G)
, glTexGen(3G)
, glTexImage1D(3G)
, glTexImage2D(3G)
, glTexSubImage1D(3G)
,
glTexSubImage2D(3G)
,
glTexParameter(3G)
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