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GLRENDERMODE()							GLRENDERMODE()

NAME
       glRenderMode - set rasterization	mode

C SPECIFICATION
       GLint glRenderMode( GLenum mode )

PARAMETERS
       mode  Specifies	the  rasterization  mode.   Three values are accepted:
	     GL_RENDER,	GL_SELECT, and	GL_FEEDBACK.   The  initial  value  is
	     GL_RENDER.

DESCRIPTION
       glRenderMode sets the rasterization mode.  It takes one argument, mode,
       which can assume	one of three predefined	values:

       GL_RENDER       Render mode. Primitives are rasterized, producing pixel
		       fragments,  which  are  written	into the frame buffer.
		       This is the normal mode and also	the default mode.

       GL_SELECT       Selection mode.	No pixel fragments are	produced,  and
		       no  change  to  the frame buffer	contents is made.  In-
		       stead, a	record of the names of primitives  that	 would
		       have  been  drawn if the	render mode had	been GL_RENDER
		       is returned in a	select buffer, which must  be  created
		       (see glSelectBuffer) before selection mode is entered.

       GL_FEEDBACK     Feedback	mode.  No pixel	fragments are produced,	and no
		       change to the frame buffer contents is made.   Instead,
		       the  coordinates	 and attributes	of vertices that would
		       have been drawn if the render mode had  been  GL_RENDER
		       is returned in a	feedback buffer, which must be created
		       (see glFeedbackBuffer) before feedback mode is entered.

       The return value	of glRenderMode	is determined by the  render  mode  at
       the  time  glRenderMode is called, rather than by mode.	The values re-
       turned for the three render modes are as	follows:

       GL_RENDER       0.

       GL_SELECT       The number of hit records  transferred  to  the	select
		       buffer.

       GL_FEEDBACK     The  number of values (not vertices) transferred	to the
		       feedback	buffer.

       See the glSelectBuffer and glFeedbackBuffer reference  pages  for  more
       details concerning selection and	feedback operation.

NOTES
       If an error is generated, glRenderMode returns 0	regardless of the cur-
       rent render mode.

ERRORS
       GL_INVALID_ENUM is generated if mode is not one of the  three  accepted
       values.

       GL_INVALID_OPERATION is generated if glSelectBuffer is called while the
       render mode is GL_SELECT, or if glRenderMode is	called	with  argument
       GL_SELECT before	glSelectBuffer is called at least once.

       GL_INVALID_OPERATION  is	 generated if glFeedbackBuffer is called while
       the render mode is GL_FEEDBACK, or if glRenderMode is called with argu-
       ment GL_FEEDBACK	before glFeedbackBuffer	is called at least once.

       GL_INVALID_OPERATION  is	 generated if glRenderMode is executed between
       the execution of	glBegin	and the	corresponding execution	of glEnd.

ASSOCIATED GETS
       glGet with argument GL_RENDER_MODE

SEE ALSO
       glFeedbackBuffer, glInitNames, glLoadName,  glPassThrough,  glPushName,
       glSelectBuffer

								GLRENDERMODE()

NAME | C SPECIFICATION | PARAMETERS | DESCRIPTION | NOTES | ERRORS | ASSOCIATED GETS | SEE ALSO

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