GLCOPYTEXSUBIMAGE1D(3UNIX Programmer's ManGLCOPYTEXSUBIMAGE1D(3G)
NAME
glCopyTexSubImage1D - copy a one-dimensional texture subim-
age
C SPECIFICATION
void glCopyTexSubImage1D( GLenum target,
GLint level,
GLint xoffset,
GLint x,
GLint y,
GLsizei width )
PARAMETERS
target Specifies the target texture. Must be
GL_TEXTURE_1D.
level Specifies the level-of-detail number. Level 0 is
the base image level. Level n is the nth mipmap
reduction image.
xoffset Specifies the texel offset within the texture
array.
x, y Specify the window coordinates of the left corner
of the row of pixels to be copied.
width Specifies the width of the texture subimage.
DESCRIPTION
glCopyTexSubImage1D 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 ori-
ginally 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
MirBSD #10-current Printed 2021-12-07 1
GLCOPYTEXSUBIMAGE1D(3UNIX Programmer's ManGLCOPYTEXSUBIMAGE1D(3G)
outside the read window associated with the current render-
ing 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.
NOTES
glCopyTexSubImage1D 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>log2 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 GETS
glGetTexImage
glIsEnabled with argument GL_TEXTURE_1D
SEE ALSO
glCopyPixels(3G), glCopyTexImage1D(3G),
glCopyTexImage2D(3G), glCopyTexSubImage2D(3G),
glCopyTexSubImage3D(3G), glPixelStore(3G),
glPixelTransfer(3G), glReadBuffer(3G), glTexEnv(3G),
glTexGen(3G), glTexImage1D(3G), glTexImage2D(3G),
MirBSD #10-current Printed 2021-12-07 2
GLCOPYTEXSUBIMAGE1D(3UNIX Programmer's ManGLCOPYTEXSUBIMAGE1D(3G)
glTexImage3D(3G), glTexParameter(3G), glTexSubImage1D(3G),
glTexSubImage2D(3G), glTexSubImage3D(3G)
MirBSD #10-current Printed 2021-12-07 3