Only update transform component if the physics body is dynamic

The simulation does not affect static bodies at all and kinematic bodies
are expected to end up in the externally specified position.

diff --git a/source/game/physicssystem.cpp b/source/game/physicssystem.cpp
index 210706cfe7d71c5b79af3ef121334fa6e03c2cb2..f2455e28b7c8772e242d80d095e332fb7e1ffa5d 100644 (file)
--- a/source/game/physicssystem.cpp
+++ b/source/game/physicssystem.cpp
@@ -115,6 +115,9 @@ void PhysicsSystem::tick(Time::TimeDelta dt)
                                b.physics_body->move_kinematic(tv.position, tv.rotation, dt);
                        else
                                b.physics_body->set_transform(tv.position, tv.rotation);
+
+                       if(b.body->is_kinematic() || !b.motion)
+                               b.transform_generation = transform->get_read_generation();
                }
 
                if(motion_changed)
@@ -127,18 +130,20 @@ void PhysicsSystem::tick(Time::TimeDelta dt)
        world.step(dt/Time::sec);
 
        for(SimulatedRigidBody &b: rigid_bodies)
-       {
-               Handle<Transform> transform = b.entity->get_transform();
-               transform->set_position(b.physics_body->get_position());
-               transform->set_rotation(b.physics_body->get_rotation());
-               b.transform_generation = transform->get_write_generation();
                if(b.motion)
                {
+                       if(!b.body->is_kinematic())
+                       {
+                               Handle<Transform> transform = b.entity->get_transform();
+                               transform->set_position(b.physics_body->get_position());
+                               transform->set_rotation(b.physics_body->get_rotation());
+                               b.transform_generation = transform->get_write_generation();
+                       }
+
                        b.motion->set_linear_velocity(b.physics_body->get_linear_velocity());
                        b.motion->set_angular_velocity(b.physics_body->get_angular_velocity());
                        b.motion_generation = b.motion->get_write_generation();
                }
-       }
 
        for(const Events::Collision &c: collision_queue)
                event_source.emit<Events::Collision>(c);