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






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


  .SH "C SPECIFICATION"




      .HP 432u void glReadBuffer(GLenum mode);


      .HP 816u void glNamedFramebufferReadBuffer(GLuint framebuffer,
GLenum mode);




  .SH "PARAMETERS"





      .PP framebuffer




                     Specifies the name of the framebuffer object for
           glNamedFramebufferReadBuffer function.


                 .RE

                 .PP 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.


                     .RE



                 .SH "DESCRIPTION"



                   .PP 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.


                   .PP 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.


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


                   .PP 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.



                 .SH "ERRORS"



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


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


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



                 .SH "ASSOCIATED GETS"



                   .PP glGet() with argument GL_READ_BUFFER



                   .SH "VERSION SUPPORT"

                       .TS allbox tab(:); lB cB s s s s s s s s s s s lB cB cB
               cB cB cB cB cB cB cB cB cB cB.  T{

               T}:T{ OpenGL Version T} T{ Function / Feature Name T}:T{ 2.0
               T}:T{ 2.1 T}:T{ 3.0 T}:T{ 3.1 T}:T{ 3.2 T}:T{ 3.3 T}:T{ 4.0
               T}:T{ 4.1 T}:T{ 4.2 T}:T{ 4.3 T}:T{ 4.4 T}:T{ 4.5 T} l c c c c
               c c c c c c c c l c c c c c c c c c c c c.  T{
               glNamedFramebufferReadBuffer T}:T{ - T}:T{ - T}:T{ - T}:T{ -
               T}:T{ - T}:T{ - T}:T{ - T}:T{ - T}:T{ - T}:T{ - T}:T{ - T}:T{
               <?> T} T{ glReadBuffer T}:T{ <?> T}:T{ <?> T}:T{ <?> T}:T{ <?>
               T}:T{ <?> T}:T{ <?> T}:T{ <?> T}:T{ <?> T}:T{ <?> T}:T{ <?>
               T}:T{ <?> T}:T{ <?> T}



                   .SH "SEE ALSO"

                       .PP glCopyTexImage1D(), glCopyTexImage2D(),
               glCopyTexSubImage1D(), glCopyTexSubImage2D(),
               glCopyTexSubImage3D(), glDrawBuffer(), glReadPixels()


                   .SH "COPYRIGHT"

                       .PP 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
               https://khronos.org/registry/OpenGL-Refpages/LICENSES/LicenseRef-FreeB.txt.



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

[FIXME: source]                   07/04/2024                  GLREADBUFFER(3G)