NAME    [Toc]    [Back]

       glDrawBuffer - specify which color buffers are to be drawn
       into

SYNOPSIS    [Toc]    [Back]

       void glDrawBuffer(
               GLenum mode );

PARAMETERS    [Toc]    [Back]

       Specifies up to four color buffers to be drawn into.  Symbolic
  constants  GL_NONE,  GL_FRONT_LEFT, GL_FRONT_RIGHT,
       GL_BACK_LEFT, GL_BACK_RIGHT, GL_FRONT,  GL_BACK,  GL_LEFT,
       GL_RIGHT,  GL_FRONT_AND_BACK,  and  GL_AUXi,  where  i  is
       between  0  and  ``GL_AUX_BUFFERS''   -1,   are   accepted
       (GL_AUX_BUFFERS is not the upper limit; use glGet to query
       the number of available aux buffers.) The initial value is
       GL_FRONT  for  single-buffered  contexts,  and GL_BACK for
       double-buffered contexts.

DESCRIPTION    [Toc]    [Back]

       When colors are written to  the  frame  buffer,  they  are
       written  into  the  color  buffers  specified  by  glDrawBuffer().
 The specifications  are  as  follows:  No  color
       buffers  are written.  Only the front left color buffer is
       written.  Only the front right color  buffer  is  written.
       Only the back left color buffer is written.  Only the back
       right color buffer is written.  Only the  front  left  and
       front  right  color  buffers  are  written. If there is no
       front right color buffer, only the front left color buffer
       is  written.   Only  the  back  left  and back right color
       buffers are written. If  there  is  no  back  right  color
       buffer,  only the back left color buffer is written.  Only
       the front left and back left color buffers are written. If
       there  is  no  back left color buffer, only the front left
       color buffer is written.  Only the front  right  and  back
       right color buffers are written. If there is no back right
       color buffer, only the front right color buffer  is  written.
   All  the  front and back color buffers (front left,
       front right, back left, back right) are written. If  there
       are  no  back color buffers, only the front left and front
       right color buffers are written. If  there  are  no  right
       color  buffers,  only  the  front left and back left color
       buffers are written. If there are no right or  back  color
       buffers,  only  the  front  left  color buffer is written.
       Only auxiliary color buffer i is written.

       If more than one color buffer  is  selected  for  drawing,
       then  blending  or  logical  operations  are  computed and
       applied independently for each color buffer and  can  produce
 different results in each buffer.

       Monoscopic contexts include only left buffers, and stereoscopic
 contexts include both left and right buffers. Likewise,
 single-buffered contexts include only front buffers,
       and double-buffered contexts include both front  and  back
       buffers. The context is selected at GL initialization.

NOTES    [Toc]    [Back]

       It is always the case that GL_AUXi = GL_AUX0 + i.

ERRORS    [Toc]    [Back]

       GL_INVALID_ENUM  is  generated  if mode is not an accepted
       value.

       GL_INVALID_OPERATION is generated if none of  the  buffers
       indicated by mode exists.

       GL_INVALID_OPERATION  is  generated  if  glDrawBuffer() is
       executed between the execution of glBegin() and the corresponding
 execution of glEnd().

ASSOCIATED GETS    [Toc]    [Back]

       glGet() with argument GL_DRAW_BUFFER
       glGet() with argument GL_AUX_BUFFERS

SEE ALSO    [Toc]    [Back]

       glBlendFunc(3),  glColorMask(3),  glIndexMask(3),  glLogicOp(3), glReadBuffer



                                                 glDrawBuffer(3G)