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GLCLEARBUFFER(3G)                                OpenGL 3.3                                GLCLEARBUFFER(3G)



NAME
       glClearBuffer - clear individual buffers of the currently bound draw framebuffer

C SPECIFICATION
       void glClearBufferiv(GLenum buffer, GLint drawBuffer, const GLint * value);

       void glClearBufferuiv(GLenum buffer, GLint drawBuffer, const GLuint * value);

       void glClearBufferfv(GLenum buffer, GLint drawBuffer, const GLfloat * value);

       void glClearBufferfi(GLenum buffer, GLint drawBuffer, GLfloat depth, GLint stencil);

PARAMETERS
       buffer
           Specify the buffer to clear.

       drawBuffer
           Specify a particular draw buffer to clear.

       value
           For color buffers, a pointer to a four-element vector specifying R, G, B and A values to clear
           the buffer to. For depth buffers, a pointer to a single depth value to clear the buffer to. For
           stencil buffers, a pointer to a single stencil value to clear the buffer to.

       depth
           The value to clear a depth render buffer to.

       stencil
           The value to clear a stencil render buffer to.

DESCRIPTION
       glClearBuffer* clears the specified buffer to the specified value(s). If buffer is GL_COLOR, a
       particular draw buffer GL_DRAWBUFFERi is specified by passing i as drawBuffer. In this case, value
       points to a four-element vector specifying the R, G, B and A color to clear that draw buffer to. If
       buffer is one of GL_FRONT, GL_BACK, GL_LEFT, GL_RIGHT, or GL_FRONT_AND_BACK, identifying multiple
       buffers, each selected buffer is cleared to the same value. Clamping and conversion for fixed-point
       color buffers are performed in the same fashion as glClearColor().

       If buffer is GL_DEPTH, drawBuffer must be zero, and value points to a single value to clear the depth
       buffer to. Only glClearBufferfv should be used to clear depth buffers. Clamping and conversion for
       fixed-point depth buffers are performed in the same fashion as glClearDepth().

       If buffer is GL_STENCIL, drawBuffer must be zero, and value points to a single value to clear the
       stencil buffer to. Only glClearBufferiv should be used to clear stencil buffers. Masing and type
       conversion are performed in the same fashion as glClearStencil().


       glClearBufferfi may be used to clear the depth and stencil buffers.  buffer must be GL_DEPTH_STENCIL
       and drawBuffer must be zero.  depth and stencil are the depth and stencil values, respectively.

       The result of glClearBuffer is undefined if no conversion between the type of value and the buffer
       being cleared is defined. However, this is not an error.

ERRORS
       GL_INVALID_ENUM is generated by glClearBufferif, glClearBufferfv and glClearBufferuiv if buffer is
       not GL_COLOR, GL_FRONT, GL_BACK, GL_LEFT, GL_RIGHT, GL_FRONT_AND_BACK, GL_DEPTH or GL_STENCIL.


       GL_INVALID_ENUM is generated by glClearBufferfi if buffer is not GL_DEPTH_STENCIL.


       GL_INVALID_VALUE is generated if buffer is GL_COLOR, GL_FRONT, GL_BACK, GL_LEFT, GL_RIGHT, or
       GL_FRONT_AND_BACK and drawBuffer is greater than or equal to GL_MAX_DRAW_BUFFERS.


       GL_INVALID_VALUE is generated if buffer is GL_DEPTH, GL_STENCIL or GL_DEPTH_STENCIL and drawBuffer is
       not zero.

SEE ALSO
       glClearColor(), glClearDepth(), glClearStencil(), glClear()


COPYRIGHT
       Copyright (C) 2010 Khronos Group. This material may be distributed subject to the terms and
       conditions set forth in the Open Publication License, v 1.0, 8 June 1999.
       http://opencontent.org/openpub/.



OpenGL 3.3                                       03/08/2011                                GLCLEARBUFFER(3G)