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
Other small changes...
- KX_Camera and KX_Light didnt have get/setitem access in their PyType definition.
- CList.from_id() error checking for a long was checking for -1 against an unsigned value (own fault)
- CValue::SpecialRelease was incrementing an int for no reason.
- renamed m_attrlist to m_attr_dict since its a PyDict type.
- removed custom getattro/setattro functions for KX_Scene and KX_GameObject, use py_base_getattro, py_base_setattro for all subclasses of PyObjectPlus.
- lowercase windows.h in VideoBase.cpp for cross compiling.
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.
- action attribute wasnt checking for NULL (own fault)
- KX_Scene getCamera wasnt checking for NULL
- CListValue had asserts for not yet implimented functionality, this would close blender. Better to print an error if the user manages to run this functions (I managed to by CListValue.count([1,2,3]))
- 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()
Added the method into the PyType so python knows about the methods (its supposed to work this way).
This means in the future the api can use PyType_Ready() to store the methods in the types dictionary.
Python3 removes Py_FindMethod and we should not be using it anyway since its not that efficient.
Python dir(ob) for game types now includes attributes names,
* Use "__dict__" rather then "__methods__" attribute to be Python 3.0 compatible
* Added _getattr_dict() for getting the method and attribute names from a PyObject, rather then building it in the macro.
* Added place holder *::Attribute array, needed for the _getattr_up macro.
* 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.
scene.getObjectList()[-1] works like a python sequence.
removed some STR_String creation that was only used to do comparisons, in a simple expressions benchmark this made logic use 4% less overall.
* removed macros that were not used much, some misleading.
* removed error string setting calls that overwrote the error set by PyArg_ParseTuple with a less useful one.
* use python macros Py_RETURN_NONE, Py_RETURN_TRUE, Py_RETURN_FALSE
PYobject type has changed
Usual C++ pickyness about implicit casts
debug made with erwin. thanks
Note to python mainteners :
even if it compiles there is a *Huge* list of warnings about deprecated
and incompatible pointers in api2.2. this should be corrected
Add Python Mapping method to CListValue
Fix Bernoulli bool distribution python method for random actuator
Fix Python IpoActuator methods setProperty and force acts local
Make data objects private
Better sort method for polygon materials - much easier to understand