Bullet crashes when updating position of kinematic object

[Bob666]

Hi all

I have a problem when using Bullet, OpenSceneGraph and osgBullet. I have a couple of boxes which are falling down onto a gound. Then I created a Sphere which I can manually move around. The boxes behave as they should, but I can't get the sphere to work. If i set it up as the boxes, it falls down, which isn't what I want. I set the collision flag btCollisionObject::CF_KINEMATIC_OBJECT and want to set the position using

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 ...->getMotionState()->setWorldTransform(trans);

this would set the new position using a btTransform->setOrigin onto an osgbBullet::MotionState. I Then can see in the output that osgBullet sets the new position, but after a couple of steps, I get an assertion:

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Assertion failed: s != btScalar(0.0), file bullet-2.77\src\linearmath\btQuaternion.h, line 188

The problem is, that the the value bullet want's to divide gets somehow -1.#IND000...

Can somebody help me or point out how to manually set a position of an object when using osgBullet?
Thanks
Bob

[Kanttori]

Maybe you're not initializing the btTransform's rotation-part? Try ...

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btTransform trans;

// Initialize transform (both basis and origin to "no transform")
trans.setIdentity();

// And then set the location
trans.setOrigin( loc );

... and you should have a valid btTransform.

[Bob666]

Great, that did the trick...

Thanks a lot.