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

2 files changed, 18 insertions, 8 deletions

diff --git a/source/gameengine/VideoTexture/FilterSource.h b/source/gameengine/VideoTexture/FilterSource.h
index 6385ed5108f..254e0a02679 100644
--- a/source/gameengine/VideoTexture/FilterSource.h
+++ b/source/gameengine/VideoTexture/FilterSource.h
@@ -225,7 +225,7 @@ protected:
 				// otherwise if only vertical interpolation is needed
 			}
 		}
-		else if ((y & 1) == 1)
+		else if ((y & 1) == 1) {
 			// if this pixel is on the edge
 			if (isEdge(x, y, size))
 			{
@@ -239,6 +239,7 @@ protected:
 				d = interpolV(m_buffU + offset) - 128;
 				e = interpolV(m_buffV + offset) - 128;
 			}
+		}
 		// convert to RGB
 		// R = clip(( 298 * C           + 409 * E + 128) >> 8)
 		// G = clip(( 298 * C - 100 * D - 208 * E + 128) >> 8)
diff --git a/source/gameengine/VideoTexture/ImageRender.cpp b/source/gameengine/VideoTexture/ImageRender.cpp
index 6ef62f64d3f..9a3c4fea70e 100644
--- a/source/gameengine/VideoTexture/ImageRender.cpp
+++ b/source/gameengine/VideoTexture/ImageRender.cpp
@@ -434,26 +434,35 @@ static int ImageMirror_init (PyObject * pySelf, PyObject * args, PyObject * kwds
 	{
 		// get scene pointer
 		KX_Scene * scenePtr (NULL);
-        if (scene != NULL && PyObject_TypeCheck(scene, &KX_Scene::Type)) 
-            scenePtr = static_cast<KX_Scene*>(scene);
-        else
+        if (scene != NULL && PyObject_TypeCheck(scene, &KX_Scene::Type))
+            scenePtr = static_cast<KX_Scene*>BGE_PROXY_REF(scene);
+		else
             THRWEXCP(SceneInvalid, S_OK);
-
+		
+		if(scenePtr==NULL) /* incase the python proxy reference is invalid */
+			THRWEXCP(SceneInvalid, S_OK);
+		
 		// get observer pointer
 		KX_GameObject * observerPtr (NULL);
 		if (observer != NULL && PyObject_TypeCheck(observer, &KX_GameObject::Type))
-            observerPtr = static_cast<KX_GameObject*>(observer);
+            observerPtr = static_cast<KX_GameObject*>BGE_PROXY_REF(observer);
         else if (observer != NULL && PyObject_TypeCheck(observer, &KX_Camera::Type))
-            observerPtr = static_cast<KX_Camera*>(observer);
+            observerPtr = static_cast<KX_Camera*>BGE_PROXY_REF(observer);
 		else
             THRWEXCP(ObserverInvalid, S_OK);
+		
+		if(observerPtr==NULL) /* incase the python proxy reference is invalid */
+			THRWEXCP(ObserverInvalid, S_OK);
 
 		// get mirror pointer
 		KX_GameObject * mirrorPtr (NULL);
 		if (mirror != NULL && PyObject_TypeCheck(mirror, &KX_GameObject::Type))
-            mirrorPtr = static_cast<KX_GameObject*>(mirror);
+            mirrorPtr = static_cast<KX_GameObject*>BGE_PROXY_REF(mirror);
 		else
             THRWEXCP(MirrorInvalid, S_OK);
+		
+		if(mirrorPtr==NULL) /* incase the python proxy reference is invalid */
+			THRWEXCP(MirrorInvalid, S_OK);
 
         // locate the material in the mirror
 		RAS_IPolyMaterial * material = getMaterial(mirror, materialID);