Search found 25 matches
- Fri Apr 29, 2022 7:44 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Static `btConvexHullShape` Not Participating in Collisions
- Replies: 2
- Views: 4063
Re: Static `btConvexHullShape` Not Participating in Collisions
Does the object properly collide when you supply it with a different shape but leave all other code unchanged? Replacing it with a box, I saw that collisions failed there too. Comparing that with my working box code, I was able to trace it down to a problem with the transforms—specifically, the tra...
- Thu Apr 28, 2022 1:35 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Static `btConvexHullShape` Not Participating in Collisions
- Replies: 2
- Views: 4063
Static `btConvexHullShape` Not Participating in Collisions
I'm trying to make a simple square static pyramid collision object. It seems I'm supposed to do this with `btConvexHullShape`: btConvexHullShape* shape = new btConvexHullShape; shape->addPoint(btVector3(-1,-1,0)); shape->addPoint(btVector3( 1,-1,0)); shape->addPoint(btVector3( 1, 1,0)); shape->addPo...
- Mon Oct 17, 2016 2:16 am
- Forum: General Bullet Physics Support and Feedback
- Topic: btSoftBody Internal Forces
- Replies: 1
- Views: 2871
btSoftBody Internal Forces
Hi, I'm trying to get some kind of measurement of internal forces from btSoftBody. (I need to measure the stress on each link for an engineering simulation. This would also be useful for computing tension in ropes, tearing cloth, etc.) I have found a few scattered posts , but no answers. I also trie...
- Wed Nov 19, 2014 8:37 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Volume of btConvexHullShape
- Replies: 2
- Views: 4487
Volume of btConvexHullShape
I need to calculate the volume of a "btConvexHullShape" (more accurately, I need to compute a mass, but I'll do this through a density). Short of implementing my own convex hull algorithm, what should I do? I considered making a temporary "btConvexTriangleMeshShape" and then usin...
- Thu Mar 20, 2014 6:51 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Soft Body Self Collision Detection
- Replies: 0
- Views: 6104
Soft Body Self Collision Detection
Hi, I have found a few posts about doing various kinds of softbody collision detection with Bullet 2, but none helpful. I am specifically interested in colliding concave softbodies with themselves, with concave rigid bodies, and with other concave soft bodies. From what I've ascertained, there is so...
- Tue Nov 26, 2013 9:32 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Memory Leak from Linking
- Replies: 10
- Views: 11252
Re: Memory Leak from Linking
This still occurs in 2.82.
I'm fairly sure at least part of the problem is that the "static btClock gProfileClock;" declared at btQuickprof.cpp:21 allocates memory that is never freed.
I'm fairly sure at least part of the problem is that the "static btClock gProfileClock;" declared at btQuickprof.cpp:21 allocates memory that is never freed.
- Thu Nov 21, 2013 11:52 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: getPersistentManifold() Returns NULL
- Replies: 1
- Views: 2568
getPersistentManifold() Returns NULL
Hi, I have a compound object and I'm trying to collide it against various things. I can't seem to figure out why, but in certain situations, my code crashes since getPersistentManifold() is returning NULL. My near callback is below: void _fz_near_callback(btBroadphasePair& collisionPair, btColli...
- Tue Jun 25, 2013 7:26 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Near Callback Discard
- Replies: 1
- Views: 2979
Near Callback Discard
Hi, I need to be able to test whether to let two objects collide after detecting whether they would. For example, if there are two separate cubes, the instant they actually start to intersect is when I decide whether to let Bullet continue processing the collision. To this end, I have implemented a ...
- Sun Jun 02, 2013 9:00 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Box-Sphere Inaccurate Collision
- Replies: 2
- Views: 4223
Re: Box-Sphere Inaccurate Collision
The collision margin was exactly the problem--I had no idea it even existed!
The scene I discovered it in was a sphere of radius 10cm rolling over boxes of size 1m on a side.
Thanks!
The scene I discovered it in was a sphere of radius 10cm rolling over boxes of size 1m on a side.
Thanks!
- Wed May 29, 2013 4:12 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Box-Sphere Inaccurate Collision
- Replies: 2
- Views: 4223
Box-Sphere Inaccurate Collision
Hi, When a box (btBoxShape) and a sphere (btSphereShape) collide, the collision is very good on faces, but inaccurate at edges/corners. My tests show that on edges, the amount of penetration relative to the size of the box can range from 0.5% to 2.0%. It seems to be independent of the time step--I t...
- Wed May 15, 2013 10:35 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Guaranteed Collision Callback
- Replies: 3
- Views: 5307
Guaranteed Collision Callback
Hi, I am attempting to figure out when two objects collide. What I want: Ideally, whenever a collision actually occurs , Bullet would call a callback, giving me the option to ignore the collision or allow Bullet to continue with collision response (restitution, reaction, etc.). Some things close and...
- Thu Apr 18, 2013 10:31 pm
- Forum: Research and development discussion about Collision Detection and Physics Simulation
- Topic: Facilities for Physics-Based Animation
- Replies: 0
- Views: 5214
Facilities for Physics-Based Animation
I'm looking for a way to animate humanoid characters in a physically-based manner. I looked around a bit, but wasn't able to find anything useful in the way of a toolkit--mostly it's just technical papers on the topic. I figured I would ask the people who follow such things more closely. My requirem...
- Sun Apr 14, 2013 1:50 am
- Forum: General Bullet Physics Support and Feedback
- Topic: BT_DECLARE_ALIGNED_ALLOCATOR new Operator Overload
- Replies: 4
- Views: 6787
Re: BT_DECLARE_ALIGNED_ALLOCATOR new Operator Overload
Figured it out. The library indeed didn't overload "new", but it did #define it to something else, for purposes of catching memory leaks: #define DEBUG_NEW new( _NORMAL_BLOCK, __FILE__, __LINE__ ) #define new DEBUG_NEW Is it possible to keep this definition, or something similar, but still...
- Sun Apr 14, 2013 12:13 am
- Forum: General Bullet Physics Support and Feedback
- Topic: BT_DECLARE_ALIGNED_ALLOCATOR new Operator Overload
- Replies: 4
- Views: 6787
Re: BT_DECLARE_ALIGNED_ALLOCATOR new Operator Overload
*Bump* I don't know why this could be happening. The other library doesn't overload new as far as I know (although it certainly uses it). The problem doesn't seem to occur if the library's header files are included after Bullet's and if no "new" allocations happen for Bullet objects in tha...
- Sun Apr 07, 2013 7:09 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Memory Leak from Linking
- Replies: 10
- Views: 11252
Re: Memory Leak from Linking
So memory leak appears after you add functionality, which is never executed? In that case, are you sure you destroy all objects you created? physics->removeRigidBody(...); delete RigidBody; delete CollisionShape; Are you sure it's not your code causing leak at all? Exactly. The code that's causing ...