Search found 13 matches

by linksan
Thu Jun 18, 2009 4:03 am
Forum: General Bullet Physics Support and Feedback
Topic: Softbody Wheels for racing sim
Replies: 4
Views: 5305

Re: Softbody Wheels for racing sim

Raycast vehicles would solve my problem, I however need to be able to apply torque directly to the wheels. I have experimented with the raycast vehicle, it works well but isn't that realistic. I played around with the softbody demos but couldn't figure out how to make an object stiffer. What paramet...
by linksan
Wed Jun 17, 2009 9:55 pm
Forum: General Bullet Physics Support and Feedback
Topic: Softbody Wheels for racing sim
Replies: 4
Views: 5305

Softbody Wheels for racing sim

Hi all, In the process of making a racing sim I realized that using cylinders for wheels causes problems with grip/handling if the wheel is not parallel to the ground. I was thinking about moving to softbodies for wheels because they could conform to the ground. Are softbodies stable at high angular...
by linksan
Fri May 22, 2009 7:45 pm
Forum: General Bullet Physics Support and Feedback
Topic: point to point spring constraint possible?
Replies: 6
Views: 11028

Re: point to point spring constraint possible?

Yes that sound exactly like what I need :)
glad to hear that it's coming soon.

Thanks
by linksan
Thu May 21, 2009 12:07 am
Forum: General Bullet Physics Support and Feedback
Topic: point to point spring constraint possible?
Replies: 6
Views: 11028

point to point spring constraint possible?

Hi,

I was wondering whether it is possible to create a spring constraint from one point to another allowing full rotation?
slider constraints don't seem to allow that

it would be something like a six dof constraint with motors

Thank you.
by linksan
Wed Sep 24, 2008 10:50 pm
Forum: General Bullet Physics Support and Feedback
Topic: Help: pure collision detection on large number of spheres
Replies: 6
Views: 4238

Re: Help: pure collision detection on large number of spheres

Thank you very much :D .
After spacing the objects out more I was able to run 1000000 bodies with about 1.2 GB of memory.


Thanks for your help.
by linksan
Wed Sep 24, 2008 9:20 pm
Forum: General Bullet Physics Support and Feedback
Topic: Help: pure collision detection on large number of spheres
Replies: 6
Views: 4238

Re: Help: pure collision detection on large number of spheres

To see what makes the program terminate I copied what collisionWorld does when performDiscreteCollisionDetection() is called I changed: if (collisionWorld) { collisionWorld->performDiscreteCollisionDetection(); } To: btDispatcher* dispatcher1; btDispatcherInfo dispatchInfo; if (collisionWorld) { col...
by linksan
Wed Sep 24, 2008 3:37 pm
Forum: General Bullet Physics Support and Feedback
Topic: Help: pure collision detection on large number of spheres
Replies: 6
Views: 4238

Re: Help: pure collision detection on large number of spheres

I'm using Bullet 2.71 I tried btDbvtBroadphase and it added the collision objects to the collision world faster but still automatically terminated. I attached a zip with the code, collision detection .exe and data generator .exe The generated data, even zipped was too big to attach. Run "DataGe...
by linksan
Tue Sep 23, 2008 11:17 pm
Forum: General Bullet Physics Support and Feedback
Topic: Help: pure collision detection on large number of spheres
Replies: 6
Views: 4238

Re: Help: pure collision detection on large number of spheres

Any ideas?

I have tried increasing the m_defaultMaxCollisionAlgorithmPoolSize and m_defaultMaxPersistentManifoldPoolSize to 10 times the number of objects but it hasn't helped.

Any help would be appreciated.

Thanks.
by linksan
Mon Sep 22, 2008 5:56 pm
Forum: General Bullet Physics Support and Feedback
Topic: Help: pure collision detection on large number of spheres
Replies: 6
Views: 4238

Help: pure collision detection on large number of spheres

My program loads data for 30000 spheres (x_data, y_data, z_data, r_data) creates and adds the sphere objects into the btCollisionWorld and then performs collision. detection Relevant Code: btVector3 worldAabbMin(-1000,-1000,-1000); btVector3 worldAabbMax(1000,1000,1000); collisionConfiguration = new...
by linksan
Tue Jun 24, 2008 7:49 pm
Forum: General Bullet Physics Support and Feedback
Topic: Ghost collisions/non dynamic collisions with collada import
Replies: 1
Views: 2088

Ghost collisions/non dynamic collisions with collada import

Hey all, I'm working on a racing game and was implementing a system to tell the user how much of the track is completed and if they are going in the right direction. To do this I create vertical planes that intersect the track at regular intervals, the theory is that if the player passes the planes ...
by linksan
Thu Jun 05, 2008 2:14 pm
Forum: General Bullet Physics Support and Feedback
Topic: Optimizing collision detection for a large heightfield
Replies: 1
Views: 2455

Optimizing collision detection for a large heightfield

Hi, I'm working on a simple racing game and am using a btHeightfieldTerrainShape as the ground. With a heightfield of 128x128 (as in the vehicle demo) my game runs at full speed. When I increase the mesh size to 256x256 or greater the game slows down. Is it possible to ignore collisions outside of a...
by linksan
Fri May 23, 2008 7:18 pm
Forum: General Bullet Physics Support and Feedback
Topic: collision impulse and normal
Replies: 5
Views: 5071

Re: collision impulse and normal

Thanks for your help, I got it working :D
by linksan
Fri May 23, 2008 4:39 pm
Forum: General Bullet Physics Support and Feedback
Topic: collision impulse and normal
Replies: 5
Views: 5071

collision impulse and normal

Hi, I'm relatively new to bullet and need help on how to get information from collisions

I have a room full of rigid body boxes, how could I determine the impulse force from collisions on these boxes ?
How could I determine the normal vector from a collision these boxes?

thanks in advance