UPBGE: Fix parent for physics object conversion.

Previously in CcdPhysicsEnvironment::ConvertObject we iterate over all
the parents from the object tree to find the closer object possibly
used as a compound shape parent. But by doing this we affected the
search of just the root parent object to disable dynamic or just for
tracking (e.g for fh spring).
To found both the root parent and the root compound parent, two
variables are used in COnvertObject, compoundParent and parentRoot.
Also to clairfy, the function in physics controller named SetParentCtrl
is rename SetParentRoot as it was used to set the root parent controller
only, not the parent controller.

Fix issue: #634.

Author: panzergame

source/gameengine/Physics/Bullet/CcdPhysicsController.cpp

@@ -173,7 +173,7 @@ CcdPhysicsController::CcdPhysicsController(const CcdConstructionInfo& ci)
 	m_newClientInfo = 0;
 	m_registerCount = 0;
 	m_softBodyTransformInitialized = false;
-	m_parentCtrl = 0;
+	m_parentRoot = nullptr;
 	// copy pointers locally to allow smart release
 	m_MotionState = ci.m_MotionState;
 	m_collisionShape = ci.m_collisionShape;
@@ -766,7 +766,7 @@ void CcdPhysicsController::WriteDynamicsToMotionState()
 // controller replication
 void CcdPhysicsController::PostProcessReplica(class PHY_IMotionState *motionstate, class PHY_IPhysicsController *parentctrl)
 {
-	SetParentCtrl((CcdPhysicsController *)parentctrl);
+	SetParentRoot((CcdPhysicsController *)parentctrl);
 	m_softBodyTransformInitialized = false;
 	m_MotionState = motionstate;
 	m_registerCount = 0;

source/gameengine/Physics/Bullet/CcdPhysicsController.h

@@ -566,7 +566,7 @@ class CcdPhysicsController : public PHY_IPhysicsController
 	int m_registerCount;            // needed when multiple sensors use the same controller
 	CcdConstructionInfo m_cci;//needed for replication
 
-	CcdPhysicsController *m_parentCtrl;
+	CcdPhysicsController *m_parentRoot;
 
 	int m_savedCollisionFlags;
 	short m_savedCollisionFilterGroup;
@@ -823,19 +823,14 @@ class CcdPhysicsController : public PHY_IPhysicsController
 		return m_cci.m_physicsEnv;
 	}
 
-	void SetParentCtrl(CcdPhysicsController *parentCtrl)
+	void SetParentRoot(CcdPhysicsController *parentCtrl)
 	{
-		m_parentCtrl = parentCtrl;
+		m_parentRoot = parentCtrl;
 	}
 
-	CcdPhysicsController *GetParentCtrl()
+	CcdPhysicsController *GetParentRoot() const
 	{
-		return m_parentCtrl;
-	}
-
-	const CcdPhysicsController *GetParentCtrl() const
-	{
-		return m_parentCtrl;
+		return m_parentRoot;
 	}
 
 	virtual bool IsDynamic()

source/gameengine/Physics/Bullet/CcdPhysicsEnvironment.cpp

@@ -811,7 +811,7 @@ void CcdPhysicsEnvironment::ProcessFhSprings(double curTime, float interval)
 		if (body && (ctrl->GetConstructionInfo().m_do_fh || ctrl->GetConstructionInfo().m_do_rot_fh)) {
 			//re-implement SM_FhObject.cpp using btCollisionWorld::rayTest and info from ctrl->getConstructionInfo()
 			//send a ray from {0.0, 0.0, 0.0} towards {0.0, 0.0, -10.0}, in local coordinates
-			CcdPhysicsController *parentCtrl = ctrl->GetParentCtrl();
+			CcdPhysicsController *parentCtrl = ctrl->GetParentRoot();
 			btRigidBody *parentBody = parentCtrl ? parentCtrl->GetRigidBody() : nullptr;
 			btRigidBody *cl_object = parentBody ? parentBody : body;
 
@@ -2692,21 +2692,34 @@ void CcdPhysicsEnvironment::ConvertObject(BL_BlenderSceneConverter& converter, K
 	CcdConstructionInfo ci;
 	class CcdShapeConstructionInfo *shapeInfo = new CcdShapeConstructionInfo();
 
-	Object *blenderparent = blenderobject->parent;
-	Object *rootparent = nullptr;
-	// Find the upper parent object using compound shape.
-	while (blenderparent) {
-		if ((blenderparent->gameflag & OB_CHILD) && (blenderobject->gameflag & (OB_COLLISION | OB_DYNAMIC | OB_RIGID_BODY)) &&
-			!(blenderobject->gameflag & OB_SOFT_BODY))
-		{
-			rootparent = blenderparent;
+	Object *blenderRoot = blenderobject->parent;
+	Object *blenderCompoundRoot = nullptr;
+	// Iterate over all parents in the object tree.
+	{
+		Object *parentit = blenderobject->parent;
+		while (parentit) {
+			// If the parent is valid for compound parent shape, update blenderCompoundRoot.
+			if ((parentit->gameflag & OB_CHILD) && (blenderobject->gameflag & (OB_COLLISION | OB_DYNAMIC | OB_RIGID_BODY)) &&
+				!(blenderobject->gameflag & OB_SOFT_BODY))
+			{
+				blenderCompoundRoot = parentit;
+			}
+			// Continue looking for root parent.
+			blenderRoot = parentit;
+
+			parentit = parentit->parent;
 		}
-		blenderparent = blenderparent->parent;
 	}
 
-	KX_GameObject *parent = nullptr;
-	if (rootparent) {
-		parent = converter.FindGameObject(rootparent);
+	KX_GameObject *compoundParent = nullptr;
+	if (blenderCompoundRoot) {
+		compoundParent = converter.FindGameObject(blenderCompoundRoot);
+		isbulletsoftbody = false;
+	}
+
+	KX_GameObject *parentRoot = nullptr;
+	if (blenderRoot) {
+		parentRoot = converter.FindGameObject(blenderRoot);
 		isbulletsoftbody = false;
 	}
 
@@ -2982,7 +2995,7 @@ void CcdPhysicsEnvironment::ConvertObject(BL_BlenderSceneConverter& converter, K
 	if (isCompoundChild) {
 		//find parent, compound shape and add to it
 		//take relative transform into account!
-		CcdPhysicsController *parentCtrl = (CcdPhysicsController *)parent->GetPhysicsController();
+		CcdPhysicsController *parentCtrl = (CcdPhysicsController *)compoundParent->GetPhysicsController();
 		BLI_assert(parentCtrl);
 
 		// only makes compound shape if parent has a physics controller (i.e not an empty, etc)
@@ -2995,7 +3008,7 @@ void CcdPhysicsEnvironment::ConvertObject(BL_BlenderSceneConverter& converter, K
 
 			// compute the local transform from parent, this may include several node in the chain
 			SG_Node *gameNode = gameobj->GetSGNode();
-			SG_Node *parentNode = parent->GetSGNode();
+			SG_Node *parentNode = compoundParent->GetSGNode();
 			// relative transform
 			MT_Vector3 parentScale = parentNode->GetWorldScaling();
 			parentScale[0] = MT_Scalar(1.0f) / parentScale[0];
@@ -3136,11 +3149,12 @@ void CcdPhysicsEnvironment::ConvertObject(BL_BlenderSceneConverter& converter, K
 		}
 	}
 
-	if (parent)
+	if (parentRoot) {
 		physicscontroller->SuspendDynamics(false);
+	}
 
-	CcdPhysicsController *parentCtrl = parent ? (CcdPhysicsController *)parent->GetPhysicsController() : 0;
-	physicscontroller->SetParentCtrl(parentCtrl);
+	CcdPhysicsController *parentCtrl = parentRoot ? static_cast<CcdPhysicsController *>(parentRoot->GetPhysicsController()) : nullptr;
+	physicscontroller->SetParentRoot(parentCtrl);
 }
 
 void CcdPhysicsEnvironment::SetupObjectConstraints(KX_GameObject *obj_src, KX_GameObject *obj_dest,