This changes how the BGE classes and Python work together, which hasnt changed since blender went opensource.
The main difference is PyObjectPlus - the base class for most game engine classes, no longer inherit from PyObject, and cannot be cast to a PyObject.
This has the advantage that the BGE does not have to keep 2 reference counts valid for C++ and Python.
Previously C++ classes would never be freed while python held a reference, however this reference could be problematic eg: a GameObject that isnt in a scene anymore should not be used by python, doing so could even crash blender in some cases.
Instead PyObjectPlus has a member "PyObject *m_proxy" which is lazily initialized when python needs it. m_proxy reference counts are managed by python, though it should never be freed while the C++ class exists since it holds a reference to avoid making and freeing it all the time.
When the C++ class is free'd it sets the m_proxy reference to NULL, If python accesses this variable it will raise a RuntimeError, (check the isValid attribute to see if its valid without raising an error).
- This replaces the m_zombie bool and IsZombie() tests added recently.
In python return values that used to be..
return value->AddRef();
Are now
return value->GetProxy();
or...
return value->NewProxy(true); // true means python owns this C++ value which will be deleted when the PyObject is freed
There were also some problems with int to python conversion
- assigning a PyLong to a KX_GameObject from python would raise an error
- PyLong were coerced into floats when used with internal CValue arithmetic
Changes...
- PyLong is converted into CIntValue for coercing and assigning from python
- CValue's generic GetNumber() function returns a double rather then a float.
- Print an error when a PyType cant be coerced into a CValue
Tested with python, expressions and property sensor.
- setting the scene attributes would always add to the scenes custom dictionary.
- new CListValue method from_id(id)
so you can store a Game Objects id and use it to get the game object back.
ob_id = id(gameOb)
...
gameOb = scene.objects.from_id(ob_id)
This is useful because names are not always unique.
- Make BGE's ListValue types convert to python lists for printing since the CValue GetText() function didnt work well- printing lists as [,,,,,] for scene objects and mesh materials for eg.
- Check attributes are descriptor types before casting.
- py_getattr_dict use the Type dict rather then Method and Attribute array.
- Initialize python types with PyType_Ready, which adds methods to the type dictionary.
- use Pythons get/setattro (uses a python string for the attribute rather then char*). Using basic C strings seems nice but internally python converts them to python strings and discards them for most functions that accept char arrays.
- Method lookups use the PyTypes dictionary (should be faster then Py_FindMethod)
- Renamed __getattr -> py_base_getattro, _getattr -> py_getattro, __repr -> py_base_repr, py_delattro, py_getattro_self etc.
From here is possible to put all the parent classes methods into each python types dictionary to avoid nested lookups (api has 4 levels of lookups in some places), tested this but its not ready yet.
Simple tests for getting a method within a loop show this to be between 0.5 and 3.2x faster then using Py_FindMethod()
* fixed segfaults in CListValue.index(val) and CListValue.count(val) when the pyTypes could not be converted into a CValue.
* added scene.objects to replace scene.getObjectList()
* added function names to PyArg_ParseTuple() so errors will include the function names
* removed cases of PyArg_ParseTuple(args,"O",&pyobj) where METH_O ensures a single argument.
* Made PyObjectFrom use ugly python api rather then Py_BuildValue(), approx %40 speedup for functions that return Python vector and matrix types like ob.orientation.
Use 'const char *' rather then the C++ 'STR_String' type for the attribute identifier of python attributes.
Each attribute and method access from python was allocating and freeing the string.
A simple test with getting an attribute a loop shows this speeds up attribute lookups a bit over 2x.
(adding)
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
also the Makefile.in's were from previous patch adding
the system depend stuff to configure.ac
Kent
--
mein@cs.umn.edu
