Search found 9 matches
- Sat Oct 15, 2011 9:19 am
- Forum: General Bullet Physics Support and Feedback
- Topic: bullet, bsp, performance
- Replies: 7
- Views: 8545
Re: bullet, bsp, performance
Hi gogiii. I've also found bullets speed for static geometry suboptimal. A few other things I've found out: - Set setForceUpdateAllAabbs(false); for your world. - Set setActivationState(DISABLE_SIMULATION); for static collision objects. - Try to keep the number of static objects small. - Batch them ...
- Thu Mar 10, 2011 3:18 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Many static objects
- Replies: 6
- Views: 8853
Re: Many static objects
Turns out that I've missed to setActivationState(DISABLE_SIMULATION) for my static objects. After applying it the results look much better. Though there is still the overhead of simulation island recalculation and isActive() check for all collision objects. 6500 static objects ...Profiling: stepSimu...
- Sat Mar 05, 2011 10:15 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Questions about joints, usage and design of Bullet...
- Replies: 8
- Views: 6251
Re: Too many questions about using and design of Bullet...
an in-depth comparison (insertion/removal/query/raycast/optimal body counts and sizes...) of broadphase algorithms That would be awesome. If you plan to do it, please share your results. I also recommend to look at/hack the demos to get an idea about the limitations/performance. From my personal us...
- Sat Feb 26, 2011 12:23 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Many static objects
- Replies: 6
- Views: 8853
Re: Many static objects
Using BVH acceleration structure of btCompoundShape seems to help (debug build, 2400 objects in compound, updateActions runs 4 ray casts). current: ...Profiling: stepSimulation (total running time: 176.646 ms) --- ...0 -- synchronizeMotionStates (0.01 %) :: 0.026 ms / frame (1 calls) ...1 -- interna...
- Thu Feb 24, 2011 2:41 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Many static objects
- Replies: 6
- Views: 8853
Re: Many static objects
A more extreme example 2400 static objects and 1 rigid body using btDbvtBroadphase: ......Profiling: internalSingleStepSimulation (total running time: 2.455 ms) --- ......0 -- updateActivationState (0.08 %) :: 0.002 ms / frame (1 calls) ......1 -- updateActions (16.99 %) :: 0.417 ms / frame (1 calls...
- Thu Feb 24, 2011 10:17 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Many static objects
- Replies: 6
- Views: 8853
Many static objects
Hi guys, I am working on a car sim. The worlds consist of a lot static geometry with a 1-8 cars and some few dynamic track objects. the cars are using raycasts for wheels. Up until now I've been batching the geometry into a single btBvhTriangleMeshShape. But with the numbers of objects increasing I ...
- Thu Jun 10, 2010 9:42 am
- Forum: General Bullet Physics Support and Feedback
- Topic: btGeneric6DofSpringConstraint damping
- Replies: 3
- Views: 5866
Re: btGeneric6DofSpringConstraint damping
Assuming that Bullets constraint implementation is based on the one from ODE: http://opende.sourceforge.net/wiki/index.php/Manual_%28Joint_Types_and_Functions%29#Stops_and_motor_parameters For the btGeneric6DofSpringConstraint this means that for damping = 0 we have Coloumb friction (m_targetVelocit...
- Wed Jun 09, 2010 5:08 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Gears simulation with Bullet
- Replies: 17
- Views: 11852
Re: Gears simulation with Bullet
Hi, you will have to write your own code. Bullet has a simple demo vehicle, but it is not a vehicle dynamics simulation library.
- Tue Jun 08, 2010 4:49 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: btGeneric6DofSpringConstraint damping
- Replies: 3
- Views: 5866
btGeneric6DofSpringConstraint damping
Hi, What kind of friction model is used by the btGeneric6DofSpringConstraint? The code doesn't look like it is viscous. I haven't been able to figure out any relation to the viscous damping coefficient or damping rate(damped harmonic oscillator). Is it possible to modify btGeneric6DofSpringConstrain...