Real-Time Physics Simulation Forum

norm the result by dividing by the last component (unless it's zero). it is generally easier to work with normed matrices which have sc = 1. the skew part sort of makes things difficult otherwise all your elements stay normed. i for one like to distinguish between elements with the last component 0 ...

Just a quick question: why bother doing physics on the GPU? It is the bottleneck with doing all the fancy drawing and shading of much less objects than the physics can handle. The average GPU is a GMA anyways...

btTransform stores rotation information as a 3x3matrix internally (which also covers scaling). Hence you lose part of the rotation information when converting to it. It can't tell the difference between 0 and 360 degrees of rotation.

oh ok, what you need to do is add a btTypedConstraint,
see src/BulletDynamics/ConstraintSolver/ to find out what types of constraints are available,
also check out some of the sample code such as the constraint demo

objects in a compound shape are fixed together statically. you can not specify any degrees of freedom.

Well, probably it is stable enough for only 2 objects. I haven't tested that. However if you have several bodies linked together (such as in a skeleton) the constraints seem to give in.

you add the sub shapes with the addChildShape function. void btCompoundShape::addChildShape(const btTransform& localTransform,btCollisionShape* shape); (keep in mind that you have to take care of allocation/deallocation of the child shapes yourself) The origin of your compound shape should be it...

Usually by placing both shapes into a compound shape. Constraints are currently not stable enough.

shouldn't that be

setCollisionFlags(btCollisionObject::CF_NO_CONTACT_RESPONSE);

uhm, what's wrong with simply using cmake? (the way i do it)

is it just me or did setAngularFactor(0.0) become ineffective?

in void btDiscreteDynamicsWorld::updateAabbs()

there is a cast btSimpleBroadphase* bp = (btSimpleBroadphase*)m_broadphasePairCache;

but i don't think it's safe to cast m_broadphasePairCache into a btSimpleBroadphase since it can be a btAxisSweep3.

I have a simple chain of objects connected via btPoint2PointConstraint or btHingeConstraints. There is a static object on one end and a large mass on the other. The problem is I want to increase the stiffness of the constraints so that it doesn't stretch apart when the forces of of both ends are to ...

What is the most effective way of applying a rotation (as part of an animation sequence) to a rigid body representing an armature?