Search found 149 matches

by c6burns
Sun Feb 09, 2014 9:20 pm
Forum: General Bullet Physics Support and Feedback
Topic: Manifolds num ok but no contact except near the margin.
Replies: 5
Views: 2900

Re: Manifolds num ok but no contact except near the margin.

Those two code snippets are clearly not doing the same thing. If you initialized the transform in the first snippet like this, then they would be: btTransform world_transform(m_player_collider_objects[ i ]->getWorldTransform()); The first snippet is clearing out the rotation. The second is preservin...
by c6burns
Sun Feb 09, 2014 4:08 pm
Forum: General Bullet Physics Support and Feedback
Topic: time step simulation independently for different objects
Replies: 8
Views: 6763

Re: time step simulation independently for different objects

IMHO changing the way the physical world is stepped is completely unnecessary for networking the simulation. When you asked about this, I thought you were going to be trying to do something way crazier than just networking. I think you will only make more work for yourself, but that's certainly your...
by c6burns
Thu Feb 06, 2014 10:47 pm
Forum: General Bullet Physics Support and Feedback
Topic: Using bullet on Android
Replies: 4
Views: 3883

Re: Using bullet on Android

Ah OK, I assumed the problem for you was getting it built for the platform. How it works is identical from platform to platform ... the only difference being under-the-hood math optimization based on available instructions for your CPU. I have the same physics code in Win/Lin/Mac/Android. That's why...
by c6burns
Thu Feb 06, 2014 4:36 pm
Forum: General Bullet Physics Support and Feedback
Topic: Using bullet on Android
Replies: 4
Views: 3883

Re: Using bullet on Android

Why would that exist? Do you need convincing that it actually runs on android? Because it does. EDIT: I guess this wasn't a very helpful post so I will add that I have seen people just dump all the files into their android project and build it this way. I did this at first, but in the end I used CMa...
by c6burns
Thu Feb 06, 2014 1:03 am
Forum: General Bullet Physics Support and Feedback
Topic: FPS dropped significantly after adding Constraints
Replies: 9
Views: 6177

Re: FPS dropped significantly after adding Constraints

You are doing 500 iterations in the solver and you are surprised at the FPS drop :shock:
by c6burns
Wed Feb 05, 2014 1:34 pm
Forum: General Bullet Physics Support and Feedback
Topic: Inverted obj import in BulletSharp?
Replies: 3
Views: 3854

Re: Inverted obj import in BulletSharp?

Just flip the one axis that's getting inverted
by c6burns
Wed Feb 05, 2014 1:33 pm
Forum: General Bullet Physics Support and Feedback
Topic: Bullet 3
Replies: 2
Views: 2672

Re: Bullet 3

I doubt anything is different about the kinematic character controller. Bullet3 is about the GPU based physics pipeline.
by c6burns
Tue Feb 04, 2014 3:26 pm
Forum: General Bullet Physics Support and Feedback
Topic: Multithreaded raycasting.
Replies: 5
Views: 6047

Re: Multithreaded raycasting.

Interesting, I didn't know about this. Look in the Benchmark and ConcaveRaycast demos for #ifdef BATCH_RAYCASTER I guess you'll have to define that before you can see how it works. Note that this isn't going to make raycasting threadsafe. It looks like it uses a thread barrier to perform raycasts in...
by c6burns
Mon Feb 03, 2014 1:05 pm
Forum: General Bullet Physics Support and Feedback
Topic: Get Rotation in MotionState
Replies: 3
Views: 2493

Re: Get Rotation in MotionState

Sanity check, you are passing params in the order (w, x, y, z) and not (x, y, z, w) ?
by c6burns
Mon Feb 03, 2014 6:49 am
Forum: General Bullet Physics Support and Feedback
Topic: Multithreaded raycasting.
Replies: 5
Views: 6047

Re: Multithreaded raycasting.

Even reading non-atomic values can cause tearing, and anything worth reading is not going to be atomic (eg. floats and vectors and etc). I don't see how you would assume raycasting into the physical world from another thread would be safe. But anyway, it isn't.
by c6burns
Thu Jan 30, 2014 11:57 pm
Forum: General Bullet Physics Support and Feedback
Topic: rayTest - didn't get all rigid bodies
Replies: 3
Views: 2236

Re: rayTest - didn't get all rigid bodies

Yeah the results are definitely not sorted by distance :)
by c6burns
Thu Jan 30, 2014 11:33 am
Forum: General Bullet Physics Support and Feedback
Topic: Use shortest path between quaternions
Replies: 5
Views: 5231

Re: Use shortest path between quaternions

Sure. First of all it's really helpful to be able to debug draw direction vectors, so if you spend a bit of time on that you will be glad you did. I tore this out of a section of steering code and quickly rewrote it to make sense and be readable for your use case (again, I'm using OgreMath but it's ...
by c6burns
Tue Jan 28, 2014 12:17 am
Forum: General Bullet Physics Support and Feedback
Topic: Use shortest path between quaternions
Replies: 5
Views: 5231

Re: Use shortest path between quaternions

OK well assuming you are familiar with Ogre, or willing to look into the two methods I mentioned in OgreMath then here is some simple code. Note it is rotating the Ogre head ... which faces unit Z. Also Ogre is Y up. Lastly I assume the turret only aims left and right, not up and down: // current or...
by c6burns
Sun Jan 26, 2014 8:19 pm
Forum: General Bullet Physics Support and Feedback
Topic: Use shortest path between quaternions
Replies: 5
Views: 5231

Re: Use shortest path between quaternions

OgreMath has both a Vector3::getRotationTo (retrieve the shortest arc quat between two vectors) and a Quaternion::Slerp (spherical linear interpolation between two quats)
by c6burns
Sun Jan 26, 2014 7:04 pm
Forum: General Bullet Physics Support and Feedback
Topic: Guaranteed Collision Callback
Replies: 3
Views: 3516

Re: Guaranteed Collision Callback

The major problem with this is that a collision is not guaranteed to be detected. If two objects collide but are then completely restored all in a single stepSimulation call above, then the if-block might never be called. Isn't that the exact case for which CCD (continuous collision detection) is d...