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GLCLEAR()							     GLCLEAR()

NAME
       glClear - clear buffers to preset values

C SPECIFICATION
       void glClear( GLbitfield	mask )

PARAMETERS
       mask  Bitwise OR	of masks that indicate the buffers to be cleared.  The
	     four masks	are GL_COLOR_BUFFER_BIT,  GL_DEPTH_BUFFER_BIT,	GL_AC-
	     CUM_BUFFER_BIT, and GL_STENCIL_BUFFER_BIT.

DESCRIPTION
       glClear	sets  the bitplane area	of the window to values	previously se-
       lected by glClearColor, glClearIndex, glClearDepth, glClearStencil, and
       glClearAccum.   Multiple	color buffers can be cleared simultaneously by
       selecting more than one buffer at a time	using glDrawBuffer.

       The pixel ownership test, the scissor test, dithering, and  the	buffer
       writemasks affect the operation of glClear.  The	scissor	box bounds the
       cleared region.	Alpha function,	 blend	function,  logical  operation,
       stenciling,   texture  mapping,	and  depth-buffering  are  ignored  by
       glClear.

       glClear takes a single argument that is the bitwise OR of several  val-
       ues indicating which buffer is to be cleared.

       The values are as follows:

       GL_COLOR_BUFFER_BIT	 Indicates  the	 buffers currently enabled for
				 color writing.

       GL_DEPTH_BUFFER_BIT	 Indicates the depth buffer.

       GL_ACCUM_BUFFER_BIT	 Indicates the accumulation buffer.

       GL_STENCIL_BUFFER_BIT	 Indicates the stencil buffer.

       The value to which each buffer is cleared depends on the	setting	of the
       clear value for that buffer.

NOTES
       If  a buffer is not present, then a glClear directed at that buffer has
       no effect.

ERRORS
       GL_INVALID_VALUE	is generated if	any bit	other than  the	 four  defined
       bits is set in mask.

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

ASSOCIATED GETS
       glGet with argument GL_ACCUM_CLEAR_VALUE
       glGet with argument GL_DEPTH_CLEAR_VALUE
       glGet with argument GL_INDEX_CLEAR_VALUE
       glGet with argument GL_COLOR_CLEAR_VALUE
       glGet with argument GL_STENCIL_CLEAR_VALUE

SEE ALSO
       glClearAccum, glClearColor, glClearDepth, glClearIndex, glClearStencil,
       glDrawBuffer, glScissor

								     GLCLEAR()

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

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