glCopyTexSubImage2D(3G)glCopyTexSubImage2D(3G)NAMEglCopyTexSubImage2D - copy a two-dimensional texture subimage
GLsizei height );
Specifies the target texture. Must be GL_TEXTURE_2D. Specifies the
level-of-detail number. Level 0 is the base image level. Level n is the
nth mipmap reduction image. Specifies a texel offset in the x direc‐
tion within the texture array. Specifies a texel offset in the y
direction within the texture array. Specify the window coordinates of
the lower left corner of the rectangular region of pixels to be copied.
Specifies the width of the texture subimage. Specifies the height of
the texture subimage.
DESCRIPTIONglCopyTexSubImage2D() replaces a rectangular portion of a two-dimen‐
sional texture image with pixels from the current GL_READ_BUFFER
(rather than from main memory, as is the case for glTexSubImage2D()).
The screen-aligned pixel rectangle with lower left corner at (x, y) and
with width width and height height replaces the portion of the texture
array with x indices xoffset through xoffset+width-1, inclusive, and y
indices yoffset through yoffset+height-1, inclusive, at the mipmap
level specified by level.
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
The destination rectangle in the texture array may not include any tex‐
els outside the texture array as it was originally specified. It is not
an error to specify a subtexture with zero width or height, but such a
specification has no effect.
If any of the pixels within the specified rectangle of the current
GL_READ_BUFFER are outside the read window associated with the current
rendering context, then the values obtained for those pixels are unde‐
No change is made to the internalformat, width, height, or border
parameters of the specified texture array or to texel values outside
the specified subregion.
NOTESglCopyTexSubImage2D() is available only if the GL version is 1.1 or
Texturing has no effect in color index mode.
glPixelStore() and glPixelTransfer() modes affect texture images in
exactly the way they affect glDrawPixels().
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_OPERATION is generated if the texture array has not been
defined by a previous glTexImage2D() or glCopyTexImage2D() operation.
GL_INVALID_VALUE is generated if level is less than 0.
GL_INVALID_VALUE may be generated if level is greater than log max,
where max is the returned value of GL_MAX_TEXTURE_SIZE.
GL_INVALID_VALUE is generated if x < -b or if y < -b, where b is the
border width of the texture array.
GL_INVALID_VALUE is generated if xoffset < -b, (xoffset+width)>(w -b),
yoffset< -b, or (yoffset+height)>(h -b), where w is the GL_TEX‐
TURE_WIDTH, h is the GL_TEXTURE_HEIGHT, and b is the GL_TEXTURE_BORDER
of the texture image being modified. Note that w and h include twice
the border width.
GL_INVALID_OPERATION is generated if glCopyTexSubImage2D() is executed
between the execution of glBegin() and the corresponding execution of
ASSOCIATED GETSglGetTexImage()glIsEnabled() with argument GL_TEXTURE_2D
SEE ALSOglCopyPixels(3), glCopyTexImage1D(3), glCopyTexImage2D(3), glCopyTex‐
SubImage1D(3), glCopyTexSubImage3D(3), glPixelStore(3), glPixelTrans‐
fer(3), glReadBuffer(3), glTexEnv(3), glTexGen(3), glTexImage1D(3),
glTexImage2D(3), glTexImage3D(3), glTexParameter(3), glTexSubIm‐
age1D(3), glTexSubImage2D(3), glTexSubImage3D(3)glCopyTexSubImage2D(3G)