copy a one-dimensional texture subimage
Signature
Parameters
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
,
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
and then converted to the texture's internal format 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 associated 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.
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
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_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
,
where
max
is the returned value of
GL_MAX_TEXTURE_SIZE
.
GL_INVALID_VALUE
is generated if
,
or
,
where
is the
GL_TEXTURE_WIDTH
and
is the
GL_TEXTURE_BORDER
of the texture image being modified.
Note that
includes twice the border width.
See Also
Copyright
Copyright
1991-2006
Silicon Graphics, Inc. This document is licensed under the SGI
Free Software B License. For details, see
http://oss.sgi.com/projects/FreeB/
.