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     <STRONG>NAME</STRONG>
	  <STRONG>glDrawBuffer</STRONG> - specify which color buffers are to be drawn
	  into


     <STRONG>C</STRONG> <STRONG>SPECIFICATION</STRONG>
	  void <STRONG>glDrawBuffer</STRONG>( GLenum <EM>mode</EM> )


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

     <STRONG>DESCRIPTION</STRONG>
	  When colors are written to the frame buffer, they are
	  written into the color buffers specified by <STRONG>glDrawBuffer</STRONG>.
	  The specifications are as follows:

	  <STRONG>GL_NONE</STRONG>		   No color buffers are	written.

	  <STRONG>GL_FRONT_LEFT</STRONG>		   Only	the front left color buffer is
				   written.

	  <STRONG>GL_FRONT_RIGHT</STRONG>	   Only	the front right	color buffer
				   is written.

	  <STRONG>GL_BACK_LEFT</STRONG>		   Only	the back left color buffer is
				   written.

	  <STRONG>GL_BACK_RIGHT</STRONG>		   Only	the back right color buffer is
				   written.

	  <STRONG>GL_FRONT</STRONG>		   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.

	  <STRONG>GL_BACK</STRONG>		   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.

	  <STRONG>GL_LEFT</STRONG>		   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.

	  <STRONG>GL_RIGHT</STRONG>		   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.

	  <STRONG>GL_FRONT_AND_BACK</STRONG>	   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.

	  <STRONG>GL_AUX</STRONG><EM>i</EM>		   Only	auxiliary color	buffer <EM>i</EM> 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 <EM>left</EM>	buffers, and
	  stereoscopic contexts	include	both <EM>left</EM> and <EM>right</EM> buffers.
	  Likewise, single-buffered contexts include only <EM>front</EM>
	  buffers, and double-buffered contexts	include	both <EM>front</EM> and
	  <EM>back</EM> buffers.	 The context is	selected at GL initialization.

     <STRONG>NOTES</STRONG>
	  It is	always the case	that <STRONG>GL_AUX</STRONG>i = <STRONG>GL_AUX0</STRONG> + i.

     <STRONG>ERRORS</STRONG>
	  <STRONG>GL_INVALID_ENUM</STRONG> is generated if <EM>mode</EM> is not an accepted
	  value.

	  <STRONG>GL_INVALID_OPERATION</STRONG> is generated if none of the buffers
	  indicated by <EM>mode</EM> exists.

	  <STRONG>GL_INVALID_OPERATION</STRONG> is generated if <STRONG>glDrawBuffer</STRONG> is
	  executed between the execution of <STRONG>glBegin</STRONG> and	the
	  corresponding	execution of <STRONG>glEnd</STRONG>.
     <STRONG>ASSOCIATED</STRONG>	<STRONG>GETS</STRONG>
	  <STRONG>glGet</STRONG>	with argument <STRONG>GL_DRAW_BUFFER</STRONG>
	  <STRONG>glGet</STRONG>	with argument <STRONG>GL_AUX_BUFFERS</STRONG>

     <STRONG>SEE</STRONG> <STRONG>ALSO</STRONG>
	  <STRONG>glBlendFunc</STRONG>, <STRONG>glColorMask</STRONG>, <STRONG>glIndexMask</STRONG>, <STRONG>glLogicOp</STRONG>,
	  <STRONG>glReadBuffer</STRONG>













































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