Hinge/slider not working in PandaBullet on linux. Bug?

[tanuva]

Moin,

maybe you've heard of Panda Bullet. Integrates bullet into panda3d providing a python interface.
I've been trying to use the hinge and slider constraints and found out yesterday that these mysteriously do not work on linux (but windows) and trigger this error:

:bullet(error): setWorldTransform: trans is NAN!
:bullet(error): Overflow in AABB, object removed from simulation
:bullet(error): If you can reproduce this, please email bugs@continuousphysics.com

:bullet(error): Please include above information, your Platform, version of OS.

:bullet(error): Thanks.

enn0x, the panda bullet developer, currently has no idea what might cause that and suspects it to be some bug in bullet.
I'd be very happy if one of you could direct us somewhere...

A minimal example: http://pastebin.com/yM5PXj7f
The panda bullet wiring can be browsed here: http://panda3d.cvs.sourceforge.net/view ... rc/bullet/

[tanuva]

enn0x noted that it'd probably be expected too much of a Bullet user to understand Panda's internals for help fixing this. I didn't know one would have to understand PandaNode to help here, so I'm going to try and reproduce the problem in C++ and thereby see if its a Bullet problem after all.

[Kanttori]

Hi,

This is a bit random but last time I saw something like the NAN was when the btTransform was not properly initialized. In the python code you're setting the position but not the rotation of the objects so unless panda bullet initializes the btTransform (setIdentity() etc.) by default, I think you'll have a bad btTransform.

[tanuva]

Thanks Kanttori for your suggestion. I've made up a little example using the code from bullet examples and the wiki. That works fine which was to be expected. So we have some bug between Windows-Python and Linux-Python. If someone is interested, this (might...) continue(s) on the panda forums:
http://www.panda3d.org/forums/viewtopic.php?t=11741

For the sake of completeness, my C++ testbed: http://pastebin.com/mYRzFvMU