NAME¶
glCopyTexSubImage1D - copy a one-dimensional texture subimage
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 originally specified.
The pixels in the row are processed exactly as if
glReadPixels() 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 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¶
The
glPixelStore() mode affects texture images.
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 2 max, where
max is the returned value of
GL_MAX_TEXTURE_SIZE.
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()
SEE ALSO¶
glCopyTexImage1D(),
glCopyTexImage2D(),
glCopyTexSubImage2D(),
glCopyTexSubImage3D(),
glPixelStore(),
glReadBuffer(),
glTexImage1D(),
glTexImage2D(),
glTexImage3D(),
glTexParameter(),
glTexSubImage1D(),
glTexSubImage2D(),
glTexSubImage3D()
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/.
