Search found 29 matches

by AshMcConnell
Mon Mar 18, 2013 9:51 pm
Forum: General Bullet Physics Support and Feedback
Topic: "Jaggy" Collisions between box (car) and mesh (track)
Replies: 3
Views: 2623

Re: "Jaggy" Collisions between box (car) and mesh (track)

In case anyone has similar problems (I know it's a bit specific). I solved the problem by increasing the margin on the box and decreasing the collision material's damping (to near zero) in our own custom built physics engine.

Hope this helps!
All the best,
Ash
by AshMcConnell
Sat Jan 26, 2013 4:34 pm
Forum: General Bullet Physics Support and Feedback
Topic: "Jaggy" Collisions between box (car) and mesh (track)
Replies: 3
Views: 2623

"Jaggy" Collisions between box (car) and mesh (track)

Hi Folks, I have been trying to track this problem down for a while. I am using Bullet for collision detection, but a custom physics engine written by a physics professor friend of mine. When the car is "bottoming out" on the track the collision seems to be in the wrong direction (the normal seems t...
by AshMcConnell
Sat Jun 23, 2012 1:23 pm
Forum: Applications, Games, Demos or Movies using Bullet
Topic: Basic Demo - Unity Bullet Physics
Replies: 1
Views: 7023

Re: Basic Demo - Unity Bullet Physics

Wow, awesome stuff. Could you let us know a little bit about how you managed to integrate it? My current project ( http://onlineracingchampionship.com ) uses bullet for collision detection and a custom vehicle dynamics physics engine. I was considering a port to Unity3d, but I couldn't figure out ho...
by AshMcConnell
Tue Dec 14, 2010 1:20 pm
Forum: General Bullet Physics Support and Feedback
Topic: Possible Memory Bug in btDbvt.cpp
Replies: 2
Views: 1247

Possible Memory Bug in btDbvt.cpp

Hi Folks, I have been experimenting with Intel's Inspector tool (30 day trial) which can detect memory issues such as Uninitialized Memory. I have found quite a few potential problems in my code, but I've noticed one in bullet too. It could be nothing, but I thought I should report it in any case. I...
by AshMcConnell
Tue Mar 02, 2010 3:52 pm
Forum: General Bullet Physics Support and Feedback
Topic: Strange bouncing after update to newer Bullet version
Replies: 1
Views: 1125

Re: Strange bouncing after update to newer Bullet version

Hi Folks,

Got it working by removing the margin and giving the cylinder proper dimensions.

All the best,
Ash
by AshMcConnell
Tue Mar 02, 2010 2:49 pm
Forum: General Bullet Physics Support and Feedback
Topic: Strange bouncing after update to newer Bullet version
Replies: 1
Views: 1125

Strange bouncing after update to newer Bullet version

Hi Folks, I have recently updated Bullet to the latest version. I had been on a REALLY old version of bullet and it had been working fine. I am simulating cars, so I am using a btCylinderShapeZ for the wheels / a box for the car itself and a btBvhTriangleMeshShape (using tris from an Ogre3d mesh). W...
by AshMcConnell
Sat Jul 28, 2007 11:24 am
Forum: Release Announcements
Topic: Bullet 2.55 SDK released: Ragdoll Demo, SIMD/Vector Math
Replies: 2
Views: 11151

Hi Erwin,

Any noticable speedups with the SIMD? Are there any benchmarks?

Keep up the good work, thanks for an excellent library! :)
All the best,
Ash
by AshMcConnell
Tue Mar 06, 2007 5:12 pm
Forum: General Bullet Physics Support and Feedback
Topic: Possible leak in btConvexConvexAlgorithm::CreateFunc
Replies: 2
Views: 1962

Good stuff, glad it was helpful.

All the best,
Ash
by AshMcConnell
Sat Mar 03, 2007 8:02 pm
Forum: General Bullet Physics Support and Feedback
Topic: Possible leak in btConvexConvexAlgorithm::CreateFunc
Replies: 2
Views: 1962

Possible leak in btConvexConvexAlgorithm::CreateFunc

Hi Folks, I'm not sure if i'm not shutting something down properly, but I am getting a small amount of memory unallocated after a run. The constructor: - btConvexConvexAlgorithm::CreateFunc::CreateFunc() { m_ownsSolvers = true; m_simplexSolver = new btVoronoiSimplexSolver(); m_pdSolver = new btGjkEp...
by AshMcConnell
Sun Jan 21, 2007 9:24 pm
Forum: General Bullet Physics Support and Feedback
Topic: Advice on optimizing world geometry for use in Bullet
Replies: 6
Views: 5839

Hi Erwin, As long as i'm doing more or less the right thing, I think it's probably fast enough for the minute and hopefully there are some optimizations that might speed things up in the next few months. I am using the current version with btAxis3Sweep and btBvhTriangleMeshShape. I think that it is ...
by AshMcConnell
Sun Jan 21, 2007 4:01 pm
Forum: General Bullet Physics Support and Feedback
Topic: Advice on optimizing world geometry for use in Bullet
Replies: 6
Views: 5839

Anyone else got any suggestions? :)

Has anyone benchmarked the difference between a lot of small collision meshes and a big one? Just wondering if it would be faster.

Thanks guys!
All the best,
Ash

PS. Making progress: - http://www.siroccoracing.com/indev/drivingLotus.avi
by AshMcConnell
Tue Jan 09, 2007 9:34 am
Forum: General Bullet Physics Support and Feedback
Topic: Advice on optimizing world geometry for use in Bullet
Replies: 6
Views: 5839

Hi Erwin, I have updated to the latest version and I reckon its about twice as quick. It is executing in around 0.8ms normally, but it occasionally it executes in 2-3ms. Even 0.8ms seems a little slow for a couple of boxes on a mesh, can you think of anything I could do to quicken things up a little...
by AshMcConnell
Mon Jan 08, 2007 10:01 pm
Forum: General Bullet Physics Support and Feedback
Topic: Advice on optimizing world geometry for use in Bullet
Replies: 6
Views: 5839

Hi Erwin, Thanks for the quick response as always :) I am indeed using the btBvhTriangleMeshShape for both meshes that represent the track. The 2 meshes have 3528 tris and 10080 respectively. The 2 "cars" are merely 2 btBoxShapes, I am not using raycasts (at least not yet). I am using a slightly dat...
by AshMcConnell
Mon Jan 08, 2007 5:58 pm
Forum: General Bullet Physics Support and Feedback
Topic: Advice on optimizing world geometry for use in Bullet
Replies: 6
Views: 5839

Advice on optimizing world geometry for use in Bullet

Hi Folks, In my test application I have a couple of meshes representing the racing track (world geometry) in my game. I am dropping a couple of cars on there (with box collision shapes). I have profiled the collision detection and its taking quite a long time (2-3ms typically) on my 3.6Ghz dual core...