glCopyTexSubImage1D — copy a one-dimensional texture subimage
void glCopyTexSubImage1D( | GLenum | target, |
GLint | level, | |
GLint | xoffset, | |
GLint | x, | |
GLint | y, | |
GLsizei | width) ; |
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.
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
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
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 or width parameters of the specified texture array or to texel values outside the specified subregion.
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
GL_MAX_TEXTURE_SIZE
.
GL_INVALID_VALUE
is generated if
GL_TEXTURE_WIDTH
of the texture image being modified.
glCopyTexImage1D, glCopyTexImage2D, glCopyTexSubImage2D, glCopyTexSubImage3D, glPixelStore, glReadBuffer, glTexImage1D, glTexImage2D, glTexImage3D, glTexParameter, glTexSubImage1D, glTexSubImage2D, glTexSubImage3D
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/.