GLCLEAR(3G) GLCLEAR(3G)

glClear - clear buffers to preset values

void glClear( GLbitfield 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.










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:



  

  
Indicates the buffers currently enabled for color writing.

  

  
Indicates the depth buffer.

  

  
Indicates the accumulation buffer.

  

  
Indicates the stencil buffer.




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








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








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.








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








glClearAccum, glClearColor, glClearDepth,
    glClearIndex, glClearStencil, glColorMask,
    glDepthMask, glDrawBuffer, glScissor,
    glStencilMask