fglCopyTexSubImage3DEXT(3G) OpenGL Reference fglCopyTexSubImage3DEXT(3G)NAMEfglCopyTexSubImage3DEXT - copy pixels into a 3D texture subimage
FORTRAN SPECIFICATION
SUBROUTINE fglCopyTexSubImage3DEXT( INTEGER*4 target,
INTEGER*4 level,
INTEGER*4 xoffset,
INTEGER*4 yoffset,
INTEGER*4 zoffset,
INTEGER*4 x,
INTEGER*4 y,
INTEGER*4 width,
INTEGER*4 height )
PARAMETERS
target The target texture. Must be GL_TEXTURE_3D_EXT
level The level-of-detail number. Level 0 is the base image level.
Level n is the nth mipmap reduction image.
xoffset A texel offset in the x direction within the texture array.
yoffset A texel offset in the y direction within the texture array.
zoffset A texel offset in the z direction within the texture array.
x The x coordinate of the lower-left corner of the pixel rectangle
to be transferred to the texture array.
y The y coordinate of the lower-left corner of the pixel rectangle
to be transferred to the texture array.
width The width of the texture subimage.
height The height of the texture subimage.
DESCRIPTIONfglCopyTexSubImage3DEXT 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 fglTexSubImage3DEXT).
The screen-aligned pixel rectangle with lower-left corner at (x, y)
having width width and height height replaces the rectangular area of the
S-T slice located at zoffset with x indices xoffset through
xoffset+width-1, inclusive, and y indices yoffset through
yoffset+height-1, inclusive (But, see discussion of GL_INTERLACE_SGIX
below).
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fglCopyTexSubImage3DEXT(3G) OpenGL Reference fglCopyTexSubImage3DEXT(3G)
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.
When GL_INTERLACE_READ_INGR is enabled, every other row of the source
pixel rectangle is read. The height of the source pixel rectangle is
equivalent to 2xheight. Only rows (y+0,y+2,...) of the source are used
to define the rows of the texture subimage that are affected by the copy.
When GL_INTERLACE_SGIX is enabled, every other row of the texture
subimage is defined. The height of the texture subimage is equivalent to
2xheight. Only rows (yoffset+0,yoffset+2,...) of the S-T slice (where
the border is considered part of the slice) are modified. A complete
video frame may be assembled in a slice of the texture array by invoking
fglCopyTexSubImage3DEXT on two consecutive video fields, with yoffset
values that differ by one.
The pixels in the rectangle are processed exactly as if fglCopyPixels 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.
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.
NOTESfglCopyTexSubImage3DEXT is part of the EXT_copy_texture extension. See
fglIntro for more information about using extensions.
ERRORS
GL_INVALID_ENUM is generated when target is not one of the allowable
values.
GL_INVALID_VALUE is generated if level is less than zero or greater than
log (max), where max is the returned value of GL_MAX_TEXTURE_SIZE.
2
GL_INVALID_VALUE is generated if xoffset<-TEXTURE_BORDER,
(xoffset+width)>(TEXTURE_WIDTH-TEXTURE_BORDER), yoffset<-TEXTURE_BORDER,
(yoffset+interlacexheight)>(TEXTURE_HEIGHT-TEXTURE_BORDER), or if
zoffset<-TEXTURE_BORDER. Where TEXTURE_WIDTH, TEXTURE_HEIGHT, and
TEXTURE_BORDER are the state values of the texture image being modified,
and interlace is 1 if GL_INTERLACE_SGIX is disabled and 2 otherwise.
Note that TEXTURE_WIDTH and TEXTURE_HEIGHT include twice the border
width.
GL_INVALID_VALUE is generated if width or height is negative.
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fglCopyTexSubImage3DEXT(3G) OpenGL Reference fglCopyTexSubImage3DEXT(3G)
GL_INVALID_OPERATION is generated when the texture array has not been
defined by a previous fglTexImage3D (or equivalent) operation.
GL_INVALID_OPERATION is generated if fglCopyTexSubImage3DEXT is executed
between the execution of fglBegin and the corresponding execution of
fglEnd.
ASSOCIATED GETS
fglGetTexImage
MACHINE DEPENDENCIESfglCopyTexSubImage3DEXT is not supported on RealityEngine,
RealityEngine2, and VTX systems.
On InfiniteReality systems, there is a performance benefit when the width
of the image to be transferred to texture memory is a multiple of 8.
Texture borders are not supported on InfiniteReality systems.
Applications should use borderless textures and GL_CLAMP_TO_EDGE_SGIS
wrap mode.
On High Impact and Maximum Impact systems, if the right side of the image
to be transferred to texture memory is not the right side of the texture,
then its index must be a multiple of 32, where index = xoffset+width.
Otherwise it will generate a GL_INVALID_VALUE error.
The SGIX_interlace extension is supported only on InfiniteReality
systems, on RealityEngine, RealityEngine2, and VTX systems, on Octane2
VPro systems, and on O2 systems.
The INGR_interlace_read extension is supported only on Octane2 VPro
systems, and on O2 systems.
SEE ALSO
fglTexImage3D, fglTexSubImage3DEXT, fglCopyPixels.
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