Probably the best place to start is by taking a working OT example vehicle and experimenting with modifying the physics parameters and learning the basic object configuration and script interface methods. That will give you a basic understanding and you can expand from there. Yes so he was using extra_force in update_frame, and in JavaScript there are only a limited set of methods, so you don't have direct access to Bullet methods. For non-controlled objects there is the dynamic_object class, like the test objects (ball, crate, capsule, barrel), which use collision meshes and physics parameters defined in the object definition file (.objdef). You can find the default OT objects in Anteworld/packages/outerra/. These days I am stearing away from JavaScript for things in the update loop and going with C++ plugins instead, for performance and the fact that C++ has better math and code structure. In my opinion scripts in update should be limited and are best used for events, and not called every frame. OT has released a basic C++ API in their GitHub, but I still recommend getting to know your way around using JS to begin with. The recently released bow and arrow demo was built using LUA scripting, which is a great option for game scripting. If you just want to work on a simple asset probably just start from an example as I suggested.
Regards,
Uriah
