Search found 32 matches

by jackskelyton
Thu Apr 10, 2008 12:33 am
Forum: General Bullet Physics Support and Feedback
Topic: Different kind of reactions with different kind of objects
Replies: 11
Views: 14276

Re: Different kind of reactions with different kind of objects

Alex -- thank you for the suggestion. As it turned out, your idea plus the 2D matrix turned out to be the perfect solution. My custom needsResponse method now looks like this (simplified): bool CustomCollisionDispatcher::needsResponse( btCollisionObject *body0, btCollisionObject *body1 ){ Actor* act...
by jackskelyton
Wed Apr 09, 2008 8:23 pm
Forum: General Bullet Physics Support and Feedback
Topic: Different kind of reactions with different kind of objects
Replies: 11
Views: 14276

Re: Different kind of reactions with different kind of objects

I implemented a simply 2D matrix with bitwise integers for filtering and that worked fine -- no need to subclass or do custom implementations of any bullet code. However, what we need is a bit more complex, and in pursuing it I noticed something interesting: We need to be able to tell when two objec...
by jackskelyton
Sat Apr 05, 2008 7:31 pm
Forum: General Bullet Physics Support and Feedback
Topic: activation states
Replies: 1
Views: 2673

activation states

what do the different activation options do for btCollisionObject? I'm looking at DISABLE_SIMULATION and I'm not sure what it's for.
by jackskelyton
Wed Mar 05, 2008 8:31 am
Forum: General Bullet Physics Support and Feedback
Topic: Translational Constraint
Replies: 5
Views: 7223

Re: Translational Constraint

We're having trouble getting this up and running... we need to constrain an actor to the XY plane like he's doing. We have two blocks of code, as follows: The first section simply creates a fixed position rigidBody to act as the constraint anchor: // Set up constraint fixed body btDefaultMotionState...
by jackskelyton
Wed Mar 05, 2008 3:00 am
Forum: General Bullet Physics Support and Feedback
Topic: Inelastic collisions
Replies: 4
Views: 4073

Re: Inelastic collisions

Of course. Just tried it, and there appears to be no change in the "bounciness" of the object with restitution at 0 or 1. Are there other properties we need to take into consideration that might be overriding it?
by jackskelyton
Wed Mar 05, 2008 2:33 am
Forum: General Bullet Physics Support and Feedback
Topic: Different kind of reactions with different kind of objects
Replies: 11
Views: 14276

Re: Different kind of reactions with different kind of objects

So, for example: how would you use this mask and filter to cause an object (a character for example) to interact with some dynamic objects but not others? I notice there are enumerated flags to represent dynamic, kinematic, and static objects. If you had a game where you wanted all the rockets to co...
by jackskelyton
Wed Mar 05, 2008 2:06 am
Forum: General Bullet Physics Support and Feedback
Topic: Inelastic collisions
Replies: 4
Views: 4073

Re: Inelastic collisions

There's no accessor to the restitution variable in btRigidBody. How do we change restitution?
by jackskelyton
Wed Mar 05, 2008 1:18 am
Forum: General Bullet Physics Support and Feedback
Topic: moving RigibBodies from one physics world to another
Replies: 2
Views: 2999

Re: moving RigibBodies from one physics world to another

Aha, excellent. That was indeed the problem. We've still got a few problems but they appear to be internal, proprietary code -- not Bullet. Thanks.
by jackskelyton
Mon Mar 03, 2008 3:31 pm
Forum: General Bullet Physics Support and Feedback
Topic: moving RigibBodies from one physics world to another
Replies: 2
Views: 2999

moving RigibBodies from one physics world to another

We're having a curious bug in our game code.. we divide levels into "scenes" with private physics worlds (btDiscreetDynamicsWorlds). When we move actors from one scene to another -- the character, for example -- we want to get his physics data in the form of his btRigidBody, load it into t...
by jackskelyton
Tue Feb 12, 2008 1:14 pm
Forum: General Bullet Physics Support and Feedback
Topic: CompoundShape messes up the contact manifold(?)
Replies: 4
Views: 3926

Re: CompoundShape messes up the contact manifold(?)

We're using 2.67. Our process is to get properties from an XML file created by our level designers and create a btRigidBody from that information. We store a pointer to our "Actor" class in the userPointer variable so that when we traverse the manifold (the code I posted above) we can mani...
by jackskelyton
Mon Feb 11, 2008 6:31 pm
Forum: General Bullet Physics Support and Feedback
Topic: CompoundShape messes up the contact manifold(?)
Replies: 4
Views: 3926

CompoundShape messes up the contact manifold(?)

We're having a bug that seems linked to using the btCompoundShape. We're doing a simple check to see if the character can jump: we traverse the PersistentManifold and for every pair of colliding objects we average all the contact points into a single point, then pass that vector into an "OnColl...
by jackskelyton
Mon Feb 11, 2008 6:10 pm
Forum: General Bullet Physics Support and Feedback
Topic: how to get objects to point up
Replies: 17
Views: 18229

Re: how to get objects to point up

Our needs are simple enough that we can make do with SetAngularFactor, but I would appreciate seeing your "tolerance cone" code, Rob. Thank you :)
by jackskelyton
Mon Feb 04, 2008 2:01 pm
Forum: General Bullet Physics Support and Feedback
Topic: how to get objects to point up
Replies: 17
Views: 18229

Re: how to get objects to point up

How do you add a soft hinge?
by jackskelyton
Wed Jan 30, 2008 2:30 pm
Forum: General Bullet Physics Support and Feedback
Topic: how to get objects to point up
Replies: 17
Views: 18229

Re: how to get objects to point up

*bump* need an answer on this.