NAME    [Toc]    [Back]

       glCopyTexSubImage3D  -  copy  a  three-dimensional texture
       subimage

SYNOPSIS    [Toc]    [Back]

       void glCopyTexSubImage3D(
               GLenum target,
               GLint level,
               GLint xoffset,
               GLint yoffset,
               GLint zoffset,
               GLint x,
               GLint y,
               GLsizei width,
               GLsizei height );

PARAMETERS    [Toc]    [Back]

       Specifies the target texture. Must be GL_TEXTURE_3D Specifies
 the level-of-detail number. Level 0 is the base image
       level. Level n is the nth mipmap reduction image.   Specifies
  a texel offset in the x direction within the texture
       array.  Specifies a texel offset in the y direction within
       the  texture  array.   Specifies  a  texel offset in the z
       direction within the texture array.   Specify  the  window
       coordinates  of  the  lower left corner of the rectangular
       region of pixels to be copied.  Specifies the width of the
       texture  subimage.   Specifies  the  height of the texture
       subimage.

DESCRIPTION    [Toc]    [Back]

       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    [Toc]    [Back]

       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    [Toc]    [Back]

       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    [Toc]    [Back]

       glGetTexImage()
       glIsEnabled() with argument GL_TEXTURE_3D

SEE ALSO    [Toc]    [Back]

       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)



                                          glCopyTexSubImage3D(3G)