Search found 14 matches
- Wed Dec 01, 2010 1:36 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Disabling collision response for some objects
- Replies: 5
- Views: 4977
Re: Disabling collision response for some objects
Doesn't that disable response for all objects? I still want my items to have a response with the world geometry, only not with the player. I have solved it now by deriving btCollisionDispatcher and adding a check in the needReponse function. I tried something like that and I 've got stuck with limi...
- Wed Dec 01, 2010 1:22 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: btCollisionShape not updated when moving btCollisionObject
- Replies: 2
- Views: 3157
Re: btCollisionShape not updated when moving btCollisionObje
btCollisionShape is instanced object. One shape can be referenced by many collision objects.
That's why there is btTransform parameter in getAabb method. You should pass transform
of your body there.
That's why there is btTransform parameter in getAabb method. You should pass transform
of your body there.
- Tue Nov 23, 2010 7:50 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: rayTest bug (ray vs box)
- Replies: 2
- Views: 3520
Re: rayTest bug (ray vs box)
personally, I found the same problem. Especially with large box it is terribly imprecious. Because whole waycast test is in fact sphere-sweep test with zero radius, I found it very inefficient too, so I rather implemented API for real ray-test and did implementation for some primitive shapes. I have...
- Mon Aug 30, 2010 10:30 am
- Forum: General Bullet Physics Support and Feedback
- Topic: RaycastVehicle coordinate system problem
- Replies: 4
- Views: 4966
Re: RaycastVehicle coordinate system problem
Well, I've working RaycastVehicle for X-axis case. I had no time to implement it compatible with other cases, so it's not final solution. Here is the first change: void btRaycastVehicle::updateWheelTransform( int wheelIndex , bool interpolatedTransform) { btWheelInfo& wheel = m_wheelInfo[ wheelI...
- Thu Aug 26, 2010 2:59 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: RaycastVehicle coordinate system problem
- Replies: 4
- Views: 4966
Re: RaycastVehicle coordinate system problem
the first problem is in this method: void btRaycastVehicle::updateWheelTransform( int wheelIndex , bool interpolatedTransform) on the start of computations there are fwd/right/up axes which seems to be OK and they correctly reflect any coordinate system. After multiplying them with rotations from wh...
- Thu Aug 26, 2010 9:59 am
- Forum: General Bullet Physics Support and Feedback
- Topic: RaycastVehicle coordinate system problem
- Replies: 4
- Views: 4966
Re: RaycastVehicle coordinate system problem
I have the same problem and I need to solve it very quickly. I'll try to fix the btRaycastVehicle code, if nobody else did it
- Sat May 30, 2009 12:34 pm
- Forum: Release Announcements
- Topic: Bullet 2.75 beta1: GPU, SPH fluids preview, new constraints
- Replies: 13
- Views: 95477
Re: Bullet 2.75 beta1: GPU, SPH fluids preview, new constraints
Just another reminder - I don't see "active objects set" in 2.75beta. It still iterates m_collisionObjects many times each simulation step. Atleast, I did myself simple modification to btDiscreteDynamicsWorld that I have separate container for rigid bodies thus many loops with such constru...
- Tue Mar 24, 2009 12:21 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Performance "problem" with large numbers of static objects
- Replies: 9
- Views: 7479
Re: Performance "problem" with large numbers of static objects
It's mostly unmodified Bullet, I have only couple of optimizations there. Anyway, the problem was activation indeed ;) Now I do this for all static objects: btCollisionObject* rb = new btCollisionObject(); rb->setCollisionFlags(btCollisionObject::CF_STATIC_OBJECT); rb->forceActivationState(ISLAND_SL...
- Mon Mar 23, 2009 5:22 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Performance "problem" with large numbers of static objects
- Replies: 9
- Views: 7479
Re: Performance "problem" with large numbers of static objects
Hi again, I just made small change, that "mp-nico" suggested, that I keep in btDiscreteDynamicsWorld pointers to only btRigidBody objects and I've got to these figures: ---------------------------------- Profiling: Root (total running time: 27.908 ms) --- 0 -- stepSimulation (99.94 %) :: 2...
- Mon Mar 23, 2009 5:00 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Mass based on scale
- Replies: 1
- Views: 2449
Re: Mass based on scale
Are you setting the computed localInertia to btRigidBody? Unless you do that, it's
considered to be static.
considered to be static.
- Mon Mar 23, 2009 4:44 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Performance "problem" with large numbers of static objects
- Replies: 9
- Views: 7479
Re: Performance "problem" with large numbers of static objects
So, here are some figures. It's island with couple of thousands trees, represented as static collision objects (I used the hint you gave me, so I changed static stuff to btCollisionObject only) There is not any dynamic rigidbody. First, dumpAll on PC with 2.4GHz P4: ---------------------------------...
- Mon Mar 23, 2009 6:11 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Performance "problem" with large numbers of static objects
- Replies: 9
- Views: 7479
Re: Performance "problem" with large numbers of static objects
Wow! I completelly missed that btCollisionObject can be used in simulation, thank you for pointing it out. It will save me a lot of memory! Probably it would be good enough hack for speeding things up until there will be some real activeList - I can make another container of rigidBodies and iterate ...
- Sun Mar 22, 2009 9:18 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Performance "problem" with large numbers of static objects
- Replies: 9
- Views: 7479
Re: Performance "problem" with large numbers of static objects
I haven't tried to group them, as I cannot combine it with another features - streaming the world and reactions of every one tree, what could be difficult when they will be grouped. Furthermore, our collision shapes are built up from convex polyhedrons. It would be easier to implement active list my...
- Sun Mar 22, 2009 6:08 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Performance "problem" with large numbers of static objects
- Replies: 9
- Views: 7479
Re: Performance "problem" with large numbers of static objects
Hello, I have the same problem. In our scenes there are thousands of static trees and a few of dynamic objects. Most of CPU time is spent on *pointless* interating whole set of rigid bodies. There is not only problem with upcast, but also with cache saturation. On certain platforms (Xbox360) it's sl...