Of What is possible - Vehicles


There is a reason why I keep comming back. Its for tinkerers to invent new things, Even if the developers didn’t intend upon it.

Last Year I dabbled on Vehicles a bit with @Balpien.Hammerer, but gave up when a critical feature was missing. It looked something like of:

This week while experimenting with my some of the whitehat scripts I made a discovery which… well, see for your self:

Still rough, relies on a very hacky solution to get working and there are major bugs to it related to avatar and the parent entity position, but otherwise looks good from ones own side. Unfortunately for everyone else the physics sync is a bit jumpy.


Indeed, the inability to truly link one or more avatars to a moving entity is still a critical problem. I have very nice physics code for vehicles, just waiting until HF gets real about attending to those critical issues.

Tick Tock folks!


Here is an example of soft linking. This avatar in the video is standing on the moving physical/dynamic buoy. The ride-on feature in this grid (it’s not found on other OpenSim grids) does just that. When any avatar is in contact with a dynamic object, stiction and ride-on (a form of soft parenting) keeps him/her on it.

Can HF do this? I would be great.


This physics jumpy thing seems to be a huge problem caused by it happening on the local machines rather than the servers, if I understood correctly. Have the devs been pestered for a responce on it? If they have a solution in mind if this is as good as its going to get.
I feel that hifi is developing a vr game engine more than a second life clone. For it to to be that it must deal with physics .grand theft auto 5 we had 5 people all over the world in one car all shooting other cars through the windows , so it can be done
So why cant we do that


Here is another example, this time of hard parenting the avatar to an entity (aka in SL terms, an avatar sitting on an object). Why it is so difficult to accomplish this in HF? I posted this vid over 8 months ago asking this question and not a single response from devs happened. Are you folks simply not caring? Is this not at all important for HF? Do you guys really expect a javascripted loop to keep an avatar and entity in sync?

Can you at least let us know if aythign is going to be done and when?

Because, without this capability built into interface, there are not going to be rideable vehicles in HF. Please! Implement the critical foundation features.


I disagree @Judas because Sinewave Space uses client based physics and it works just fine there. This issue in HF is the lack of proper soft and/or hard linking of avatars to dynamic entities. This needs to be fixed soonest.


There are two issues in discussion: Avatar parenting, and the Physics Sync issue which occurs with Physics ownership:

There is no true “Ownership” of entities. So Physics ownership applies to whom ever is manipulating it at that moment, or closest to the physics object. It works in this case, but because it’s the client that throws the new position of the entity with the server, other clients will see it in different states, depending on everyone’s connectivity: So some people see me fly this thing smoothly, others not so much.

But this also causes issues with the Avatar position vs Entity:

Now: we can absolutely now parent an avatar with an entity-
But the position and rotation can get offset, depending on who is the physics owner of the entity the avatar is attached to.

Basically, the Video I show off the sit and pilot demonstrates this:

  • While the Avatar is bound to the entity, its still running on the Avatar Mixer, separate from the Entity Mixer
  • Entity Camera stays stable on the head entity I texted unlike the avatar

I think the solution would be to handle Physical Avatar physics in the entity mixer when it is parented to An Entity, and handle all the bone and mesh data on the mixer. This currently doesnt happen.


/That is a failure of the design. When owner and that means the physics simulator in a client is doing the movement, any soft or hard linked entities/avtars to anther entity must be done together during each physics frame. This is in fact what happens when an avatar in SL style grids sit on an object. A temporary hard link has occurred.

To every one else not owning the physics simulation they are just getting a bunch of messages from the owner simulation.


As far i know, and that’s months fo told to. the client is doing everything and sent ipdates to other clients. physics and movement in high fidelity are always client side. Unless it’s changed.