docs/devinfo.rst

   1 Development Notes
   2 =================
   3
   4 Adding Extensions
   5 -----------------
   6
   7 To add a new GL extension to Mesa you have to do at least the following.
   8
   9 -  If ``glext.h`` doesn't define the extension, edit ``include/GL/gl.h``
  10    and add code like this:
  11
  12    .. code-block:: c
  13
  14            #ifndef GL_EXT_the_extension_name
  15            #define GL_EXT_the_extension_name 1
  16            /* declare the new enum tokens */
  17            /* prototype the new functions */
  18            /* TYPEDEFS for the new functions */
  19            #endif
  20
  21
  22 -  In the ``src/mapi/glapi/gen/`` directory, add the new extension
  23    functions and enums to the ``gl_API.xml`` file. Then, a bunch of
  24    source files must be regenerated by executing the corresponding
  25    Python scripts.
  26 -  Add a new entry to the ``gl_extensions`` struct in ``mtypes.h`` if
  27    the extension requires driver capabilities not already exposed by
  28    another extension.
  29 -  Add a new entry to the ``src/mesa/main/extensions_table.h`` file.
  30 -  From this point, the best way to proceed is to find another
  31    extension, similar to the new one, that's already implemented in Mesa
  32    and use it as an example.
  33 -  If the new extension adds new GL state, the functions in ``get.c``,
  34    ``enable.c`` and ``attrib.c`` will most likely require new code.
  35 -  To determine if the new extension is active in the current context,
  36    use the auto-generated ``_mesa_has_##name_str()`` function defined in
  37    ``src/mesa/main/extensions.h``.
  38 -  The dispatch tests ``check_table.cpp`` and ``dispatch_sanity.cpp``
  39    should be updated with details about the new extensions functions.
  40    These tests are run using ``meson test``.