Joints problems

Troubleshooting physics
1

Hello!



Is there any way to learn more about joints in jMonkey3? The behaviour is not as expected and most of the time we don’t understand what we do and we try in luck… I visited Bullet site to see some more documentation but it is not helpful.



And something else, is there any way to place joints from the jMonkeyPlatform?



Thank you!

2

I have to answer no to both questions :confused: So I’d be very happy when you started a wiki page on your findings while using the joints.

What excatly do you want to know? As you saw yourself, the documentation on bullet is scarce, I tried to incorporate most of my findings into the javadoc of the physics classes…

Cheers,

Normen

3

Why do we have so many problems with them and they don’t behave the way we want, that’s what I would like to know! :slight_smile:

Anyway. If we find something I’ll try to contribute to the wiki.

4

I found that if you try and constrain them too much they tend to get weird. Also, I had strange problems with “thin” physicsnodes that I tried to attach to each other (see the undone physicsragdollcontroller)… I could not quite tell if this was the jbullet implementation or if it happens in native bullet also… But these uncertainties will only go away when I move the physics to native bullet. :slight_smile:

Cheers,

Normen

5

Thank you!

6
normen said:
But these uncertainties will only go away when I move the physics to native bullet. :)

Could you tell us a little bit more about it? ;)
Since i'm heavily dependent on jbullet and physics i'm quite interested in what you are going to do.
7

I will use the native bullet version… what shall I say. Thats why I tell everybody not to use the jbullet objects directly because they will be gone when physics goes native and just be replaced by long’s that are used to reference the native bullet object.



I had a basic version of native physics for jbullet-jme (jME2) already working if you want to look at that: http://code.google.com/p/jbullet-jme/source/browse/#svn/branches/bullet-jme-work

The jME3 version will probably be similarly implemented.



Cheers,

Normen



Edit: For the user nothing should change (if you dont use jbullet classes directly ;))

8

hey, why move away from java XD

aren’t there any other alternatives?

and what about platform independence?

will there be any problems for linux users?

9

bullet is very platform independent, it should even compile on android, so no problems.



Edit: Plus, we get OpenCL acceleration :smiley: