UPBGE: Fix shape replacement for character.

Previously the shape replacement for character wasn't managed and the previous
shape was deleted without relink to the new shape.

To solve this issue CcdCharacter::ReplaceShape is implemented to replace the
shape, this function is called into ReplaceControllerShape.

As character could not use a non convex shape, some shape replacement may
fail (e.g with triangle mesh) the user notice it with the return value
of obj.replacePhysicsShape which is now a boolean.

Fix issue: #968.

Author: panzergame

doc/python_api/rst/bge_types/bge.types.KX_GameObject.rst

@@ -1064,6 +1064,12 @@ base class --- :class:`SCA_IObject`
 
       :arg gameObject: set the physics shape from this gameObjets.
       :type gameObject: string, :class:`KX_GameObject`
+      :return: True if replace succeeded, False if it failed.
+      :rtype: boolean
+
+      .. warning::
+
+         Triangle mesh shapes are not supported.
 
    .. method:: get(key[, default])
 

source/gameengine/Ketsji/KX_GameObject.cpp

@@ -2129,8 +2129,10 @@ PyObject *KX_GameObject::PyReplacePhysicsShape(PyObject *value)
 		return nullptr;
 	}
 
-	m_physicsController->ReplacePhysicsShape(gameobj->GetPhysicsController());
-	Py_RETURN_NONE;
+	if (m_physicsController->ReplacePhysicsShape(gameobj->GetPhysicsController())) {
+		Py_RETURN_TRUE;
+	}
+	Py_RETURN_FALSE;
 }
 
 static PyObject *Map_GetItem(PyObject *self_v, PyObject *item)

source/gameengine/Physics/Bullet/CcdPhysicsController.cpp

@@ -157,6 +157,12 @@ void CcdCharacter::SetVelocity(const btVector3& vel, float time, bool local)
 	setVelocityForTimeInterval(v, time);
 }
 
+void CcdCharacter::ReplaceShape(btConvexShape* shape)
+{
+	m_convexShape = shape;
+	m_ghostObject->setCollisionShape(m_convexShape);
+}
+
 void CcdCharacter::SetVelocity(const mt::vec3& vel, float time, bool local)
 {
 	SetVelocity(ToBullet(vel), time, local);
@@ -675,6 +681,10 @@ bool CcdPhysicsController::ReplaceControllerShape(btCollisionShape *newShape)
 		world->addSoftBody(newSoftBody);
 	}
 
+	if (m_characterController) {
+		m_characterController->ReplaceShape(static_cast<btConvexShape *>(newShape));
+	}
+
 	return true;
 }
 
@@ -1699,10 +1709,16 @@ bool CcdPhysicsController::ReinstancePhysicsShape(KX_GameObject *from_gameobj, R
 	return true;
 }
 
-void CcdPhysicsController::ReplacePhysicsShape(PHY_IPhysicsController *phyctrl)
+bool CcdPhysicsController::ReplacePhysicsShape(PHY_IPhysicsController *phyctrl)
 {
 	CcdShapeConstructionInfo *shapeInfo = ((CcdPhysicsController *)phyctrl)->GetShapeInfo();
 
+	if (m_characterController && ELEM(shapeInfo->m_shapeType,
+			PHY_SHAPE_COMPOUND, PHY_SHAPE_PROXY, PHY_SHAPE_EMPTY, PHY_SHAPE_COMPOUND, PHY_SHAPE_MESH))
+	{
+		return false;
+	}
+
 	// switch shape info
 	m_shapeInfo->Release();
 	m_shapeInfo = shapeInfo->AddRef();

source/gameengine/Physics/Bullet/CcdPhysicsController.h

@@ -467,6 +467,9 @@ class CcdCharacter : public btKinematicCharacterController, public PHY_ICharacte
 
 	void SetVelocity(const btVector3& vel, float time, bool local);
 
+	/// Replace current convex shape.
+	void ReplaceShape(btConvexShape *shape);
+
 	// PHY_ICharacter interface
 	virtual void Jump()
 	{
@@ -857,7 +860,7 @@ class CcdPhysicsController : public PHY_IPhysicsController, public mt::SimdClass
 	}
 
 	virtual bool ReinstancePhysicsShape(KX_GameObject *from_gameobj, RAS_Mesh *from_meshobj, bool dupli = false);
-	virtual void ReplacePhysicsShape(PHY_IPhysicsController *phyctrl);
+	virtual bool ReplacePhysicsShape(PHY_IPhysicsController *phyctrl);
 };
 
 /// DefaultMotionState implements standard motionstate, using btTransform

source/gameengine/Physics/Common/PHY_IPhysicsController.h

@@ -151,7 +151,7 @@ class PHY_IPhysicsController : public PHY_IController
 	virtual bool IsPhysicsSuspended() = 0;
 
 	virtual bool ReinstancePhysicsShape(KX_GameObject *from_gameobj, RAS_Mesh *from_meshobj, bool dupli = false) = 0;
-	virtual void ReplacePhysicsShape(PHY_IPhysicsController *phyctrl) = 0;
+	virtual bool ReplacePhysicsShape(PHY_IPhysicsController *phyctrl) = 0;
 };
 
 #endif  /* __PHY_IPHYSICSCONTROLLER_H__ */