To make it work, I had to:
- update Operators to include all of its methods in the Python API
- redefine the Freestyle modules as local classes, allowing predicates to support the __call__ method (I found out that Python does not allow modules to be callable). The API is defined in the new freestyle_init.py file.
- remove all references to former Python Freestyle API (located in source/blender/freestyle/python/, under the Freestyle.py file) and replace it with the new API file.
- normalize all constants related to the Nature class
- redefine the logical_operators.py file so that AndUP1D, OrUP1D and NotUP1D would be subclasses of a UnaryPredicate1D subclass having a operator() implementation. Using UnaryPredicate1D as a superclass would somehow prevent calls to the operator(). For the time being, I chose ContourUP1D (even though it does not really matter which subclass it is, since the __call__ method is redefined in all of these classes). I will implement this classes in C++ to get rid of the problem altogether.
- turn off a few classes that somehow are not well recognized (Noise, Curve...). I will reenable them later once I understand what's going on.
Quite a few modifications were made to finish the API:
- Freestyle's SConscript was modified to catch all files within the intern/python directory, allowing integration of future shaders implemented in C++.
- the Operators class was ported, with a special care of making its methods static (using the METH_STATIC flag in the tp_methods method definitions)
- all of the type-checking functions [ BPy_[class name]_Check(obj) ] were changed to allow subclasses to be seen as that type too: instead on looking at the ob_type value, the PyObject_IsInstance function is used.
- all of the iterators can now retrieve the object pointed to by the operator, using the getObject() method. A directedViewEdge pair is returned as a list of the two elements in the pair.
- all of the style modules were copied to a style_modules_blender/ folder and were modified to use Freestyle as a Blender's submodule. IntegrationType and MediumType was also integrated (for example, changing MEAN to IntegrationType.MEAN).
Testing now begins. If everything works correctly, I'll move on to lib3ds removal right away.
