GLREADBUFFER(3G)                [FIXME: manual]               GLREADBUFFER(3G)

NAME
       glReadBuffer, glNamedFramebufferReadBuffer - select a color buffer
       source for pixels

C SPECIFICATION
       void glReadBuffer(GLenum mode);

       void glNamedFramebufferReadBuffer(GLuint framebuffer, GLenum mode);

PARAMETERS
       framebuffer
           Specifies the name of the framebuffer object for
           glNamedFramebufferReadBuffer function.

       mode
           Specifies a color buffer. Accepted values are GL_FRONT_LEFT,
           GL_FRONT_RIGHT, GL_BACK_LEFT, GL_BACK_RIGHT, GL_FRONT, GL_BACK,
           GL_LEFT, GL_RIGHT, and the constants GL_COLOR_ATTACHMENTi.

DESCRIPTION
       glReadBuffer specifies a color buffer as the source for subsequent
       glReadPixels(), glCopyTexImage1D(), glCopyTexImage2D(),
       glCopyTexSubImage1D(), glCopyTexSubImage2D(), and glCopyTexSubImage3D()
       commands.  mode accepts one of twelve or more predefined values. In a
       fully configured system, GL_FRONT, GL_LEFT, and GL_FRONT_LEFT all name
       the front left buffer, GL_FRONT_RIGHT and GL_RIGHT name the front right
       buffer, and GL_BACK_LEFT and GL_BACK name the back left buffer. Further
       more, the constants GL_COLOR_ATTACHMENTi may be used to indicate the
       ith color attachment where i ranges from zero to the value of
       GL_MAX_COLOR_ATTACHMENTS minus one.

       Nonstereo double-buffered configurations have only a front left and a
       back left buffer. Single-buffered configurations have a front left and
       a front right buffer if stereo, and only a front left buffer if
       nonstereo. It is an error to specify a nonexistent buffer to
       glReadBuffer.

       mode is initially GL_FRONT in single-buffered configurations and
       GL_BACK in double-buffered configurations.

       For glReadBuffer, the target framebuffer object is that bound to
       GL_READ_FRAMEBUFFER. For glNamedFramebufferReadBuffer, framebuffer must
       either be zero or the name of the target framebuffer object. If
       framebuffer is zero, then the default read framebuffer is affected.

ERRORS
       GL_INVALID_ENUM is generated if mode is not one of the twelve (or more)
       accepted values.

       GL_INVALID_OPERATION is generated if mode specifies a buffer that does
       not exist.

       GL_INVALID_OPERATION is generated by glNamedFramebufferReadBuffer if
       framebuffer is not zero or the name of an existing framebuffer object.

ASSOCIATED GETS
       glGet() with argument GL_READ_BUFFER

VERSION SUPPORT

       +-----------------------------+-----------------------------------------------------------------------+
       |                             |                            OpenGL Version                             |
       +-----------------------------+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
       |Function / Feature Name      | 2.0 | 2.1 | 3.0 | 3.1 | 3.2 | 3.3 | 4.0 | 4.1 | 4.2 | 4.3 | 4.4 | 4.5 |
       +-----------------------------+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
       |glNamedFramebufferReadBuffer |  -  |  -  |  -  |  -  |  -  |  -  |  -  |  -  |  -  |  -  |  -  | <?> |
       +-----------------------------+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
       |glReadBuffer                 | <?> | <?> | <?> | <?> | <?> | <?> | <?> | <?> | <?> | <?> | <?> | <?> |
       +-----------------------------+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+

SEE ALSO
       glCopyTexImage1D(), glCopyTexImage2D(), glCopyTexSubImage1D(),
       glCopyTexSubImage2D(), glCopyTexSubImage3D(), glDrawBuffer(),
       glReadPixels()

COPYRIGHT
       Copyright (C) 1991-2006 Silicon Graphics, Inc. Copyright (C) 2011-2014
       Khronos Group. This document is licensed under the SGI Free Software B
       License. For details, see http://oss.sgi.com/projects/FreeB/.

COPYRIGHT
       Copyright (C) 1991-2006 Silicon Graphics, Inc.
       Copyright (C) 2011-2014 Khronos Group

[FIXME: source]                   05/21/2022                  GLREADBUFFER(3G)