glClear - clear buffers to preset values

glGet() with argument GL_DEPTH_CLEAR_VALUEglGet() with argument GL_COLOR_CLEAR_VALUEglGet() with argument GL_STENCIL_CLEAR_VALUE

voidglClear(GLbitfieldmask);

       Copyright © 1991-2006 Silicon Graphics, Inc.
       Copyright © 2010-2014 Khronos Group

[FIXME: source]                                    11/18/2024                                        GLCLEAR(3G)

glClear sets the bitplane area of the window to values previously selected by glClearColor, glClearDepth,
       and glClearStencil. 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_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.

GL_INVALID_VALUE is generated if any bit other than the three defined bits is set in mask.

       glClear - clear buffers to preset values

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

mask
           Bitwise OR of masks that indicate the buffers to be cleared. The three masks are GL_COLOR_BUFFER_BIT,
           GL_DEPTH_BUFFER_BIT, and GL_STENCIL_BUFFER_BIT.

glClearColor, glClearDepth, glClearStencil, glColorMask(), glDepthMask(), glDrawBuffer(), glScissor(),
       glStencilMask()

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       │          │                OpenGLVersion                                         │
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       │ Function │ 2.0 │ 2.1 │ 3.0 │ 3.1 │ 3.2 │ 3.3 │ 4.0 │ 4.1 │ 4.2 │ 4.3 │ 4.4 │ 4.5 │
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       ├──────────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┼─────┤
       │ glClear  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │  ✔  │
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