docs/specs/MESA_framebuffer_flip_y.txt

   1 Name
   2
   3     MESA_framebuffer_flip_y
   4
   5 Name Strings
   6
   7     GL_MESA_framebuffer_flip_y
   8
   9 Contact
  10
  11     Fritz Koenig <frkoenig@google.com>
  12
  13 Contributors
  14
  15     Fritz Koenig, Google
  16     Kristian Høgsberg, Google
  17     Chad Versace, Google
  18     Heinrich Fink, DAQRI
  19
  20 Status
  21
  22     Proposal
  23
  24 Version
  25
  26     Version 3, August, 2019
  27
  28 Number
  29
  30     OpenGL Extension #540
  31     OpenGL ES Extension #302
  32
  33 Dependencies
  34
  35     Requires OpenGL ES 3.0, OpenGL 4.3, or ARB_framebuffer_no_attachments.
  36
  37 Overview
  38
  39     This extension defines a new framebuffer parameter,
  40     GL_FRAMEBUFFER_FLIP_Y_MESA, that changes the behavior of the reads and
  41     writes to the framebuffer attachment points. When GL_FRAMEBUFFER_FLIP_Y_MESA
  42     is GL_TRUE, render commands and pixel transfer operations access the
  43     backing store of each attachment point with an y-inverted coordinate
  44     system. This y-inversion is relative to the coordinate system set when
  45     GL_FRAMEBUFFER_FLIP_Y_MESA is GL_FALSE.
  46
  47     Access through TexSubImage2D and similar calls will notice the effect of
  48     the flip when they are not attached to framebuffer objects because
  49     GL_FRAMEBUFFER_FLIP_Y_MESA is associated with the framebuffer object and
  50     not the attachment points.
  51
  52 IP Status
  53
  54     None
  55
  56 Issues
  57
  58     None
  59
  60 New Procedures and Functions
  61
  62     OpenGL ES must provide the following functions:
  63
  64     void FramebufferParameteriMESA(enum target, enum pname, int param);
  65     void GetFramebufferParameterivMESA(enum target, enum pname, int *params);
  66
  67 New Types
  68
  69     None
  70
  71 New Tokens
  72
  73     Accepted by the <pname> argument of FramebufferParameteriMESA and
  74     GetFramebufferParameterivMESA:
  75
  76         GL_FRAMEBUFFER_FLIP_Y_MESA                      0x8BBB
  77
  78 Interactions with OpenGL 4.3, OpenGL ES 3.1, ARB_framebuffer_no_attachments
  79 and any other versions and extensions that provide the entry points
  80 FramebufferParameteri and GetFramebufferParameteriv
  81
  82         Token GL_FRAMEBUFFER_FLIP_Y_MESA is accepted as the <pname> argument of
  83         FramebufferParameteri and GetFramebufferParameteriv.
  84
  85 Errors
  86
  87     An INVALID_OPERATION error is generated by GetFramebufferParameteriv or
  88     GetFramebufferParameterivMESA if the default framebuffer is bound
  89     to <target> and <pname> is GL_FRAMEBUFFER_FLIP_Y_MESA.
  90
  91
  92
  93
  94
  95 Revision History
  96
  97     Version 3, August, 2019
  98         Allow OpenGL ES 3.0 to implement by adding functions
  99         FramebufferParameteriMESA and GetFramebufferParameterivMESA which were
 100         previously only available in OpenGL ES 3.1.
 101
 102     Version 2, June, 2019
 103         Enable extension for OpenGL 4.3 and beyond
 104
 105     Version 1, June, 2018
 106         Initial draft (Fritz Koenig)