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       icetGetColorBuffer,icetGetDepthBuffer--  retrieves  the  last  computed
       color or depth buffer.


       #include <GL/ice-t.h>

       GLubyte   *icetGetColorBuffer   (   void  );
       GLuint    *icetGetDepthBuffer   (   void  );


       Returns a  buffer  containing  the  result  of  the  image  composition
       performed  by the last call to icetDrawFrame.  Be aware that a color or
       depth buffer  may  not  have  been  computed  with  the  last  call  to
       icetDrawFrame.   IceT  avoids the computation and network transfers for
       any unnecessary buffers unless specifically  requested  otherwise  with
       the  flags  given to the icetInputOutputBuffers function. Use a call to
       icetGetBooleanvwith   a    value    of    ICET_COLOR_BUFFER_VALID    or
       ICET_DEPTH_BUFFER_VALID  to  determine  whether either of these buffers
       are available. Attempting to get a nonexistent buffer will result  with
       a warning being emitted and NULL returned.

Return Value

       icetGetColorBufferreturns  the  color  buffer  for  the displayed tile.
       Each pixel value can be assumed to be four  consecutive  bytes  in  the
       buffer.  The  pixels  are also always aligned on 4-byte boundaries. The
       format  of  the  color  buffer  is  defined  by  the  state   parameter
       ICET_COLOR_FORMAT,  which  is  typically  either  GL_RGBA,  GL_BGRA, or

       icetGetDepthBufferreturns the depth  buffer  for  the  displayed  tile.
       Depth values are stored as 32-bit integers.

       The  width and the height of the buffer are determined by the width and
       the height of the displayed tile at the time icetDrawFrame was  called.
       If the tile layout is changed since the last call to icetDrawFrame, the
       dimensions of the buffer returned may not  agree  with  the  dimensions
       stored in the current IceT state.

       The  memory  returned  by  icetGetColorBufferand icetGetDepthBufferneed
       not, and should not, be freed. It will be reclaimed in the next call to
       icetDrawFrame.   Expect the data returned to be obliterated on the next
       call to icetDrawFrame.




               The appropriate buffer is not available, either because it  was
              not  computed  or  it  has been obliterated by a subsequent IceT


       The returned image may have a value of $(R, G, B, A) = (0,  0,  0,  0)$
       for  a  pixel instead of the true background color. This can usually be
       corrected by replacing all pixels with an alpha value  of  0  with  the
       background color.

       The buffers are stored in a shared memory pool attached to a particular
       context. As such, the buffers are not  copied  with  the  state.  Also,
       because  they  are  shared,  it is conceivable that the buffers will be
       reclaimed before the  next  call  to  icetDrawFrame.   If  this  should
       variables will be set accordingly.


       Copyright (C)2003 Sandia Corporation

       Under the terms of Contract DE-AC04-94AL85000, there is a non-exclusive
       license  for  use  of this work by or on behalf of the U.S. Government.
       Redistribution and use in source and  binary  forms,  with  or  without
       modification, are permitted provided that this Notice and any statement
       of authorship are reproduced on all copies.

See Also

       icetDrawFrame(3), icetInputOutputBuffers(3), icetGet(3)

IceT Reference                 February 14, 2008         icetGetColorBuffer(3)