glCopyTexSubImage3D — copy a three-dimensional texture subimage
void glCopyTexSubImage3D( | GLenum target, |
GLint level, | |
GLint xoffset, | |
GLint yoffset, | |
GLint zoffset, | |
GLint x, | |
GLint y, | |
GLsizei width, | |
GLsizei height) ; |
target
Specifies the target texture.
Must be GL_TEXTURE_3D
or GL_TEXTURE_2D_ARRAY
.
level
Specifies the level-of-detail number. Level 0 is the base image level. Level n is the nth mipmap reduction image.
xoffset
Specifies a texel offset in the x direction within the texture array.
yoffset
Specifies a texel offset in the y direction within the texture array.
zoffset
Specifies a texel offset in the z direction within the texture array.
x
, y
Specify the window coordinates of the lower left corner of the rectangular region of pixels to be copied.
width
Specifies the width of the texture subimage.
height
Specifies the height of the texture subimage.
glCopyTexSubImage3D
replaces a rectangular portion of a three-dimensional
or two-dimensional array texture image with pixels from the current GL_READ_BUFFER
(rather
than from main memory, as is the case for glTexSubImage3D).
The screen-aligned pixel rectangle with lower left corner at
(x
, y
) and with
width width
and height height
replaces the portion of the
texture array with x indices xoffset
through
yoffset
through
zoffset
and at the mipmap level specified by level
.
The pixels in the rectangle 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
The destination rectangle in the texture array may not include any texels outside the texture array as it was originally specified. It is not an error to specify a subtexture with zero width or height, but such a specification has no effect.
If any of the pixels within the specified rectangle 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, height, depth, or border 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_3D
.
GL_INVALID_OPERATION
is generated if the texture array has not
been defined by a previous glTexImage3D operation.
GL_INVALID_VALUE
is generated if level
is less than 0.
GL_INVALID_VALUE
may be generated if
GL_MAX_3D_TEXTURE_SIZE
if target
is GL_TEXTURE_3D
or the returned value of GL_MAX_ARRAY_TEXTURE_LAYERS
if target
is GL_TEXTURE_2D_ARRAY
.
GL_INVALID_VALUE
is generated if
GL_TEXTURE_WIDTH
,
GL_TEXTURE_HEIGHT
,
GL_TEXTURE_DEPTH
and
of the texture image being modified.
Note that
glCopyTexImage1D, glCopyTexImage2D, glCopyTexSubImage1D, glCopyTexSubImage2D, glPixelStore, glReadBuffer, glTexImage1D, glTexImage2D, glTexImage3D, glTexParameter, glTexSubImage1D, glTexSubImage2D, glTexSubImage3D
Copyright © 1991-2006 Silicon Graphics, Inc. Copyright © 2012-2013 Khronos Group. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.