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Index for Section 3G |
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Alphabetical listing for G |
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glCopyTexSubImage3D(3G)
NAME
glCopyTexSubImage3D - copy a three-dimensional texture subimage
SYNOPSIS
void glCopyTexSubImage3D(
GLenum target,
GLint level,
GLint xoffset,
GLint yoffset,
GLint zoffset,
GLint x,
GLint y,
GLsizei width,
GLsizei height );
PARAMETERS
target
Specifies the target texture. Must be GL_TEXTURE_3D
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.
DESCRIPTION
glCopyTexSubImage3D() replaces a rectangular portion of a three-dimensional
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 xoffset+width-1, inclusive, and y
indices yoffset through yoffset+height-1, inclusive, at z index zoffset and
at the mipmap level specified by level.
The pixels in the rectangle 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.
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.
NOTES
glCopyTexSubImage3D() is available only if the GL version is 1.2 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, as if they
were a two-dimensional texture. See glTexImage2D() for specific details.
ERRORS
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() or glCopyTexImage3D operation.
GL_INVALID_VALUE is generated if level is less than 0.
GL_INVALID_VALUE may be generated if level is greater than log sub 2^max,
where max is the returned value of GL_MAX_3D_TEXTURE_SIZE.
GL_INVALID_VALUE is generated if x < -b or if y < -b, where b is the border
width of the texture array.
GL_INVALID_VALUE is generated if xoffset < -b, (xoffset+width)>(w -b),
yoffset< -b, (yoffset+height)>(h -b), zoffset< -b, or zoffset>(d -b), where
w is the GL_TEXTURE_WIDTH, h is the GL_TEXTURE_HEIGHT, d is the
GL_TEXTURE_DEPTH, and b is the GL_TEXTURE_BORDER of the texture image being
modified. Note that w, h, and d include twice the border width.
GL_INVALID_OPERATION is generated if glCopyTexSubImage3D() is executed
between the execution of glBegin() and the corresponding execution of
glEnd().
ASSOCIATED GETS
glGetTexImage()
glIsEnabled() with argument GL_TEXTURE_3D
SEE ALSO
glCopyPixels(3), glCopyTexImage1D(3), glCopyTexImage2D(3),
glCopyTexSubImage1D(3), glCopyTexSubImage2D(3), glPixelStore(3),
glPixelTransfer(3), glReadBuffer(3), glTexEnv(3), glTexGen(3),
glTexImage1D(3), glTexImage2D(3), glTexImage3D(3), glTexParameter(3),
glTexSubImage1D(3), glTexSubImage2D(3), glTexSubImage3D(3)
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Index for Section 3G |
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Alphabetical listing for G |
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Top of page |
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