glCopyTexSubImage1D(3G)glCopyTexSubImage1D(3G)NAMEglCopyTexSubImage1D - copy a one-dimensional texture subimage
SYNOPSIS
void glCopyTexSubImage1D(
GLenum target,
GLint level,
GLint xoffset,
GLint x,
GLint y,
GLsizei width );
PARAMETERS
Specifies the target texture. Must be GL_TEXTURE_1D. Specifies the
level-of-detail number. Level 0 is the base image level. Level n is the
nth mipmap reduction image. Specifies the texel offset within the tex‐
ture array. Specify the window coordinates of the left corner of the
row of pixels to be copied. Specifies the width of the texture subim‐
age.
DESCRIPTIONglCopyTexSubImage1D() replaces a portion of a one-dimensional texture
image with pixels from the current GL_READ_BUFFER (rather than from
main memory, as is the case for glTexSubImage1D).
The screen-aligned pixel row with left corner at (x, y), and with
length width replaces the portion of the texture array with x indices
xoffset through "xoffset" + "width" - 1, inclusive. The destination in
the texture array may not include any texels outside the texture array
as it was originally specified.
The pixels in the row 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.
It is not an error to specify a subtexture with zero width, but such a
specification has no effect. If any of the pixels within the specified
row of the current GL_READ_BUFFER are outside the read window associ‐
ated with the current rendering context, then the values obtained for
those pixels are undefined.
No change is made to the internalformat, width, or border parameters of
the specified texture array or to texel values outside the specified
subregion.
NOTESglCopyTexSubImage1D() is available only if the GL version is 1.1 or
greater.
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
copied from the framebuffer may be processed by the imaging pipeline.
See glTexImage1D() for specific details.
ERRORS
GL_INVALID_ENUM is generated if target is not GL_TEXTURE_1D.
GL_INVALID_OPERATION is generated if the texture array has not been
defined by a previous glTexImage1D or glCopyTexImage1D operation.
GL_INVALID_VALUE is generated if level is less than 0.
GL_INVALID_VALUE may be generated if level>log sub 2 max, where max is
the returned value of GL_MAX_TEXTURE_SIZE.
GL_INVALID_VALUE is generated if y < -b or if width < -b, where b is
the border width of the texture array.
GL_INVALID_VALUE is generated if xoffset < -b, or (xoffset+width) > (w-
b), where w is the GL_TEXTURE_WIDTH, and b is the GL_TEXTURE_BORDER of
the texture image being modified. Note that w includes twice the border
width.
ASSOCIATED GETSglGetTexImage()glIsEnabled() with argument GL_TEXTURE_1D
SEE ALSOglCopyPixels(3), glCopyTexImage1D(3), glCopyTexImage2D(3), glCopyTex‐
SubImage2D(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)glCopyTexSubImage1D(3G)