Fall thru ground: how to scale everything easily?

Troubleshooting physics
1

Bullet physics seems to have serious problems with too small objects (less than 0.1f in any dimmension?).

I was thinking, if I could scale everything in a single place like:
rootNode.setLocalScale(100f); //so basically, 1f means 1cm, what will be great for dices and coins
it could be easier than implementing scaling on every Spatial and algorithm…

But when I did this my application looked weird…

I wonder if anyone have tried this?
I wonder if someone know a better approach? or I if scaling the rootNode is good but will require some tweaks?

2

This has been discussed several times before:
http://hub.jmonkeyengine.org/forum/topic/scaling-world-unit/

Might be some tricks there you could use, also, check out the bullet wiki, it has a page specifically about “scaling the world”.

1 Like
3

from your post there!
http://www.bulletphysics.org/mediawiki-1.5.8/index.php?title=Scaling_The_World

btw, there says: “Support for objects of this size has improved in Bullet 2.74.”, anyone knows what bullet version is shipped with JME3 SDK? I’m still looking in the .jar(s)

PS.: I just thought if my installation could be outdated? I thought we could update the SDK from within it (netbeans updates). But I saw no updated since I being using it again so now I am not sure…

4

following this tip: http://code.google.com/p/bullet/issues/detail?id=45#c5
so basically I did: bulletAppState.getPhysicsSpace().setAccuracy(1.0f/240f);
helped a lot!

But if I create too many objects the physics seems to become slow; may be to scale the physics world may be better, not sure tho if in the end I will still get that low framerate?