Is it possible to replicate mechanical systems within the SDK? I don't mean using func doors and dynamic props to simulate what a mechanical system might look like, but actually have a single power source which powers an entire system. Some examples of what I want to do: - Create a simple gearing system - Converting rotational movment into directional movment (like the piston in a car engine but the other way round) I've been having trouble finding the correct tools to enable this to work as there doesn't seem to be any axis constraints. Also assigning the moving brushes to suitable entities has been trial & error as func_physbox can misbehave when force is applied. Have basic newtonian physics been implemented into the soucre engine? Even things as simple as applying a force?