const shapes, and use *MotionState::setShape()

libraries/physics/src/EntityMotionState.cpp

@@ -46,7 +46,7 @@ bool entityTreeIsLocked() {
 
 
 EntityMotionState::EntityMotionState(btCollisionShape* shape, EntityItemPointer entity) :
-    ObjectMotionState(shape),
+    ObjectMotionState(nullptr),
     _entityPtr(entity),
     _entity(entity.get()),
     _serverPosition(0.0f),
@@ -71,6 +71,9 @@ EntityMotionState::EntityMotionState(btCollisionShape* shape, EntityItemPointer
     assert(_entity);
     assert(entityTreeIsLocked());
     setMass(_entity->computeMass());
+    // we need the side-effects of EntityMotionState::setShape() so we call it explicitly here
+    // rather than pass the legit shape pointer to the ObjectMotionState ctor above.
+    setShape(shape);
 }
 
 EntityMotionState::~EntityMotionState() {
@@ -264,17 +267,16 @@ bool EntityMotionState::isReadyToComputeShape() const {
 }
 
 // virtual and protected
-btCollisionShape* EntityMotionState::computeNewShape() {
+const btCollisionShape* EntityMotionState::computeNewShape() {
     ShapeInfo shapeInfo;
     assert(entityTreeIsLocked());
     _entity->computeShapeInfo(shapeInfo);
     return getShapeManager()->getShape(shapeInfo);
 }
 
-void EntityMotionState::setShape(btCollisionShape* shape) {
+void EntityMotionState::setShape(const btCollisionShape* shape) {
-    bool shapeChanged = (_shape != shape);
+    if (_shape != shape) {
-    ObjectMotionState::setShape(shape);
+        ObjectMotionState::setShape(shape);
-    if (shapeChanged) {
         _entity->setCollisionShape(_shape);
     }
 }

libraries/physics/src/EntityMotionState.h

@@ -89,8 +89,8 @@ protected:
     #endif
 
     bool isReadyToComputeShape() const override;
-    btCollisionShape* computeNewShape() override;
+    const btCollisionShape* computeNewShape() override;
-    void setShape(btCollisionShape* shape) override;
+    void setShape(const btCollisionShape* shape) override;
     void setMotionType(PhysicsMotionType motionType) override;
 
     // In the glorious future (when entities lib depends on physics lib) the EntityMotionState will be

libraries/physics/src/ObjectMotionState.cpp

@@ -62,14 +62,13 @@ ShapeManager* ObjectMotionState::getShapeManager() {
     return shapeManager;
 }
 
-ObjectMotionState::ObjectMotionState(btCollisionShape* shape) :
+ObjectMotionState::ObjectMotionState(const btCollisionShape* shape) :
     _motionType(MOTION_TYPE_STATIC),
-    _shape(nullptr),
+    _shape(shape),
     _body(nullptr),
     _mass(0.0f),
     _lastKinematicStep(worldSimulationStep)
 {
-    setShape(shape);
 }
 
 ObjectMotionState::~ObjectMotionState() {
@@ -154,12 +153,13 @@ void ObjectMotionState::setRigidBody(btRigidBody* body) {
         _body = body;
         if (_body) {
             _body->setUserPointer(this);
+            assert(_body->getCollisionShape() == _shape);
         }
         updateCCDConfiguration();
     }
 }
 
-void ObjectMotionState::setShape(btCollisionShape* shape) {
+void ObjectMotionState::setShape(const btCollisionShape* shape) {
     if (_shape != shape) {
         if (_shape) {
             getShapeManager()->releaseShape(_shape);
@@ -254,7 +254,7 @@ bool ObjectMotionState::handleHardAndEasyChanges(uint32_t& flags, PhysicsEngine*
         if (!isReadyToComputeShape()) {
             return false;
         }
-        btCollisionShape* newShape = computeNewShape();
+        const btCollisionShape* newShape = computeNewShape();
         if (!newShape) {
             qCDebug(physics) << "Warning: failed to generate new shape!";
             // failed to generate new shape! --> keep old shape and remove shape-change flag
@@ -274,7 +274,7 @@ bool ObjectMotionState::handleHardAndEasyChanges(uint32_t& flags, PhysicsEngine*
             // and clear the reference we just created
             getShapeManager()->releaseShape(_shape);
         } else {
-            _body->setCollisionShape(newShape);
+            _body->setCollisionShape(const_cast<btCollisionShape*>(newShape));
             setShape(newShape);
             updateCCDConfiguration();
         }

libraries/physics/src/ObjectMotionState.h

@@ -78,7 +78,7 @@ public:
     static void setShapeManager(ShapeManager* manager);
     static ShapeManager* getShapeManager();
 
-    ObjectMotionState(btCollisionShape* shape);
+    ObjectMotionState(const btCollisionShape* shape);
     ~ObjectMotionState();
 
     virtual void handleEasyChanges(uint32_t& flags);
@@ -110,7 +110,7 @@ public:
 
     virtual PhysicsMotionType computePhysicsMotionType() const = 0;
 
-    btCollisionShape* getShape() const { return _shape; }
+    const btCollisionShape* getShape() const { return _shape; }
     btRigidBody* getRigidBody() const { return _body; }
 
     virtual bool isMoving() const = 0;
@@ -150,17 +150,17 @@ public:
 
 protected:
     virtual bool isReadyToComputeShape() const = 0;
-    virtual btCollisionShape* computeNewShape() = 0;
+    virtual const btCollisionShape* computeNewShape() = 0;
     virtual void setMotionType(PhysicsMotionType motionType);
     void updateCCDConfiguration();
 
     void setRigidBody(btRigidBody* body);
-    virtual void setShape(btCollisionShape* shape);
+    virtual void setShape(const btCollisionShape* shape);
 
     MotionStateType _type = MOTIONSTATE_TYPE_INVALID; // type of MotionState
     PhysicsMotionType _motionType; // type of motion: KINEMATIC, DYNAMIC, or STATIC
 
-    btCollisionShape* _shape;
+    const btCollisionShape* _shape;
     btRigidBody* _body;
     float _mass;