* Using a separate dict for globals/locals for each interpreter means we
still get separation of variables and no persistence where we don't
want it, but removing sub-interpreters means pyside can work as it
uses the PyGILState_ APIs which do not support sub-interpreters.
* We import everything up front then duplicate the __main__ each time we
create a new context so we keep the __main__ pristine and muck up an
individual copy.
* Because sys is now shared, the output redirectors that overwrite
sys.stdout and sys.stderr have a NULL context, and instead they look
up a specific global which contains the actual context pointer.
* SWIG outputs two files - renderdoc_python.cpp with the main actual
wrapping code, and renderdoc.py a small module that does some
bootstrapping on python side.
* We use a custom version of SWIG that generates strong/typed enums in
python based on enum classes, so in cmake we add this custom swig
fork as an external project and compile it before generating the
wrappers. On windows there's a committed version of the SWIG binary
that gets run directly from the .pro or .vcxproj.
* The renderdoc.py gets embedded as a resource on windows or as a C
generated unsigned char array via include-bin on other platforms, so
that we can insert it into the python context without needing it to
sit around on disk somewhere in sys.path
baldurk