Development Notes
Adding Extensions
To add a new GL extension to Mesa you have to do at least the following.
-
If
glext.hdoesn't define the extension, editinclude/GL/gl.hand add code like this:#ifndef GL_EXT_the_extension_name #define GL_EXT_the_extension_name 1 /* declare the new enum tokens */ /* prototype the new functions */ /* TYPEDEFS for the new functions */ #endif -
In the
src/mapi/glapi/gen/directory, add the new extension functions and enums to thegl_API.xmlfile. Then, a bunch of source files must be regenerated by executing the corresponding Python scripts. -
Add a new entry to the
gl_extensionsstruct inmtypes.hif the extension requires driver capabilities not already exposed by another extension. -
Add a new entry to the
src/mesa/main/extensions_table.hfile. - From this point, the best way to proceed is to find another extension, similar to the new one, that's already implemented in Mesa and use it as an example.
-
If the new extension adds new GL state, the functions in
get.c,enable.candattrib.cwill most likely require new code. -
To determine if the new extension is active in the current context,
use the auto-generated
_mesa_has_##name_str()function defined insrc/mesa/main/extensions.h. -
The dispatch tests
check_table.cppanddispatch_sanity.cppshould be updated with details about the new extensions functions. These tests are run usingmeson test.