One example is pg_RGBAFromObj where the implementation is defined in base.c, and also exported in base.c (and _pygame.h).
base.c has this exposing the pg_RGBAFromObj function to the c_api structure:
c_api = pg_RGBAFromObj;
Then in src_c/include/_pygame.h there is an
Also in _pygame.h, it needs to define the number of slots the base module uses. This is PYGAMEAPI_BASE_NUMSLOTS. So if you were adding another function, you need to increment this PYGAMEAPI_BASE_NUMSLOTS number.
Then to use the pg_RGBAFromObj in other files,
include the "pygame.h" file,
they have to make sure base is imported with:
Examples that use pg_RGBAFromObj are: _freetype.c, color.c, gfxdraw.c, and surface.c.
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