Search found 44 matches

by sipickles
Thu Aug 06, 2009 10:15 am
Forum: General Bullet Physics Support and Feedback
Topic: How to use Bullet to control a smooth camera...
Replies: 11
Views: 18523

Re: How to use Bullet to control a smooth camera...

Fair enough if you wanna do it that way. Just sounds to me like you are reprogramming a system already provided by bullet. For example: at every step I keep only about 20% of the old velocity and set 80% of the new one; this is very good to limit camera bounciness due to its very low mass). Why not ...
by sipickles
Wed Aug 05, 2009 11:09 am
Forum: General Bullet Physics Support and Feedback
Topic: How to use Bullet to control a smooth camera...
Replies: 11
Views: 18523

Re: How to use Bullet to control a smooth camera...

I'm thinking that this makes the camera velocity dependent on the CPU speed, because at each (rendering) step I set the linear velocity based on getLinearVelocity(...) (basically I add velocity), and getLinearVelocity(...) can return the value I added last rendering step, without Bullet taking it i...
by sipickles
Tue Aug 04, 2009 2:34 pm
Forum: General Bullet Physics Support and Feedback
Topic: How to use Bullet to control a smooth camera...
Replies: 11
Views: 18523

Re: How to use Bullet to control a smooth camera...

Flix wrote:As I told, it .... does not affect other bodies too (its mass is too little).
Using a collision filter might be better than tiny mass? See http://bulletphysics.com/Bullet/BulletP ... c223854848
by sipickles
Tue Jul 07, 2009 7:57 am
Forum: General Bullet Physics Support and Feedback
Topic: Heap corruption
Replies: 1
Views: 2451

Heap corruption

Hi, I have a problem using bullet 2.75 in my own app, MSVC2005 winXP SP3. I have heap corruptions detected by MSVC when I do allocations of bullet objects. The debugger is pointing at: static void *btAllocDefault(size_t size) { return malloc(size); } This occurs when I create new btAxisSweep3, or if...
by sipickles
Wed Jun 24, 2009 12:27 pm
Forum: General Bullet Physics Support and Feedback
Topic: 16 byte alignment issue in vector< btVector3 >
Replies: 6
Views: 15363

Re: 16 byte alignment issue in vector< btVector3 >

I am having a similar issue. I am using boost::python to wrap c++ classes which use Bullet. If any class contains a btVector3 member, it will not compile, or if I try to expose btVector3 as a boost::python object. Here's the result: C:\boost_1_38_0\boost/python/converter/as_to_python_function.hpp(21...
by sipickles
Thu Jun 04, 2009 12:45 pm
Forum: General Bullet Physics Support and Feedback
Topic: Constraining range of rotation of rigidBody
Replies: 1
Views: 2103

Constraining range of rotation of rigidBody

Hi,

What is the best way to limit the (local) pitch and roll of a btRigidBody, whilst allowing free yaw and movement? Basically I want a vehicle which cannot flip over.

btConeTwistConstraint without any twist constraint?

Thanks

Simon
by sipickles
Wed Jun 03, 2009 6:58 pm
Forum: General Bullet Physics Support and Feedback
Topic: Strange hang after upgrading to 2.74
Replies: 3
Views: 2535

Re: Strange hang after upgrading to 2.74

Made some progress with my terrain problem, using 2.75 I hadn't realised that btHeightfieldTerrainShape ctor had changed so I was passing nonsensical values to some of the arguments. So now my models land on the terrain. Hooray! Still have the odd hammered framerate for a few seconds if I add a heig...
by sipickles
Mon Jun 01, 2009 5:59 am
Forum: General Bullet Physics Support and Feedback
Topic: Strange hang after upgrading to 2.74
Replies: 3
Views: 2535

Re: Strange hang after upgrading to 2.74

Ok, thank Erwin. I will upgrade and report back. In the meantime I've noticed the problem was caused by adding a btHeightField. Once I've removed this, my app runs smoothly and collisions all behave. (hmm forgot to try vehicle demo....) Also turning down the maxSteps of stepSimulation helped a littl...
by sipickles
Thu May 28, 2009 12:43 pm
Forum: General Bullet Physics Support and Feedback
Topic: Accelerating a PyODE simulation with Bullet+Cuda or OpenCL
Replies: 3
Views: 3389

Re: Accelerating a PyODE simulation with Bullet+Cuda or OpenCL

I am doing it the hard way. I am wrapping Bullet in boost.python. It works pretty well so far, well it did until I just broke my app (nothing to do with bullet I am sure! ;) I have a whole c++ class which performs the bullet work. My python code simply queries it from time to time. Extract from boos...
by sipickles
Tue May 26, 2009 3:47 pm
Forum: General Bullet Physics Support and Feedback
Topic: Strange hang after upgrading to 2.74
Replies: 3
Views: 2535

Strange hang after upgrading to 2.74

Hi, Just upgraded form 2.68 ->2.74 on winXP MSVC2005. Now when my app first runs, it hangs the first time btDynamicsWorld::stepSimulation is called for about 10 seconds before bursting into life. If I comment out the stepSimulation call it doesn't hang at all. This is the same code that worked fine ...
by sipickles
Sat Mar 07, 2009 9:41 am
Forum: General Bullet Physics Support and Feedback
Topic: Compensating for Roll of btRigidBody
Replies: 1
Views: 2514

Compensating for Roll of btRigidBody

Hello, I have a btRigidBody which moves in a manner similar to a helicopter - lift counters gravity, tilt provides lateral motion at the expense of lift. This works fine at first, however when I Yaw (almost like using a tail rotor) while moving (I know you dont do this in a real helicopter!) some ro...
by sipickles
Sat Feb 28, 2009 8:57 am
Forum: General Bullet Physics Support and Feedback
Topic: btQuaternion::slerp often fails assert
Replies: 1
Views: 4171

btQuaternion::slerp often fails assert

Hi, I am blending my client and server positions of btRigidBodys like this: void CModel::UpdateVelocity( const float& lx, const float& ly, const float& lz, const float& ax, const float& ay, const float& az ) { const btVector3 clientPos = m_body->getWorldTransform().getOrigin(...
by sipickles
Wed Jan 28, 2009 4:12 pm
Forum: General Bullet Physics Support and Feedback
Topic: Confused! Need to compare headings
Replies: 3
Views: 2669

Re: Confused! Need to compare headings

Thanks for the reply Dominik. That seems obvious now! I tried it and am having some strange steering behaviour - the object is not heading towards the waypoint but wandering round randomly! Here's my approach: void CModel::UpdateSteering( const float& timedelta ) { // Get waypoint position btVec...
by sipickles
Tue Jan 27, 2009 8:56 am
Forum: General Bullet Physics Support and Feedback
Topic: Confused! Need to compare headings
Replies: 3
Views: 2669

Confused! Need to compare headings

Hello, I'd like to do some simple maths but have scrambled my head! I have an object I want to steer to a waypoint. I know the position of waypoint and object, hence a vector between the two. I also know the quaternion representing the rotation of the object. I need to know the vector this quaternio...
by sipickles
Fri Dec 19, 2008 8:33 am
Forum: General Bullet Physics Support and Feedback
Topic: Collision on a Client/Server system - practical?
Replies: 3
Views: 3966

Collision on a Client/Server system - practical?

Hello, I've been tinkering with bullet for a while now. It works very well on a single local system. I've seen a few other posters who have similar problems to this, but I thought I'd start a new thread to discuss some situations and possible solutions. Situation: Server AND client both run btDiscre...