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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_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,
       glDrawBuffer, glScissor

                                                                     GLCLEAR()