BGE Python API

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

1 files changed, 0 insertions, 16 deletions

diff --git a/source/gameengine/Expressions/Value.h b/source/gameengine/Expressions/Value.h
index bcee355cda2..a687e1a493c 100644
--- a/source/gameengine/Expressions/Value.h
+++ b/source/gameengine/Expressions/Value.h
@@ -225,21 +225,6 @@ public:
 
 
 	virtual PyObject*			py_getattro(PyObject *attr);
-
-	void	SpecialRelease()
-	{
-		if (ob_refcnt == 0) /* make sure python always holds a reference */
-		{
-			_Py_NewReference(this);
-			
-		}
-		Release();
-	}
-	static void PyDestructor(PyObject *P)				// python wrapper
-	{
-	  ((CValue*)P)->SpecialRelease();
-	};
-
 	virtual PyObject*	ConvertValueToPython() {
 		return NULL;
 	}
@@ -352,7 +337,6 @@ private:
 	std::map<STR_String,CValue*>*		m_pNamedPropertyArray;									// Properties for user/game etc
 	ValueFlags			m_ValFlags;												// Frequently used flags in a bitfield (low memoryusage)
 	int					m_refcount;												// Reference Counter	
-	bool				m_zombie;												// Object is invalid put its still being referenced (by python)
 	static	double m_sZeroVec[3];	
 	static bool			m_ignore_deprecation_warnings;