GLCLEAR(3G)															       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  depth-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.

       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, glColorMask, glDepthMask, glDrawBuffer, glScissor, glStencilMask

																       GLCLEAR(3G)