glClear(3G)		       OpenGL Reference			   glClear(3G)



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_ACCUM_BUFFER_BIT,	and GL_STENCIL_BUFFER_BIT.


DESCRIPTION
     glClear sets the bitplane area of the window to values previously
     selected 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 z-buffering are ignored by glClear.

     glClear takes a single argument that is the bitwise OR of several values
     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.






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glClear(3G)		       OpenGL Reference			   glClear(3G)



     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









































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