Search found 96 matches
- Mon Jan 15, 2018 2:05 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Coordinate Space Conversions? Are there any?
- Replies: 4
- Views: 5047
Re: Coordinate Space Conversions? Are there any?
Just want to add some little things to drleviathan's great answer :- the inertia's eigenvectors align with the cardinal axes of the shape's local-frame ^ btMatrix3x3::diagonalized() will help about this. In fact, this is the only way to have a concave RigidBody that is dynamic or kinematic. There ar...
- Mon Jan 08, 2018 5:04 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Getting from Rigidbody to GameObject (architecture question)
- Replies: 1
- Views: 2761
Re: Getting from Rigidbody to GameObject (architecture question)
Yes, it supports.
See btCollisionObject::setUserPointer(void*) / getUserPointer.
See btCollisionObject::setUserPointer(void*) / getUserPointer.
- Thu Jan 04, 2018 2:02 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Custom broadphase filter for city-sized world, need advice
- Replies: 4
- Views: 4260
Re: Custom broadphase filter for city-sized world, need advice
+1 drleviathan :lol: I heard a rumor that btAxisSweep3 and bt32AxisSweep3 is faster than the generic one "with a limitation that it requires a fixed world size". It is in Sweep and Prune (SAP) in http://www.bulletphysics.org/mediawiki-1.5.8/index.php/Broadphase ^Edit: Erwin doesn't think s...
- Thu Dec 28, 2017 3:09 am
- Forum: General Bullet Physics Support and Feedback
- Topic: performDiscreteCollisionDetection (update manifold) for only a few bodies (ghost?)
- Replies: 9
- Views: 8456
Re: How to performDiscreteCollisionDetection (update manifold) for only a few bodies?
Thank drleviathan for the great detailed answer.
btPairCachingGhostObject is probably all I want (the 10-20 objects are all radar/sensor). I have never used ghost thingy before.
off-topic : It is lucky that this forum has you.
btPairCachingGhostObject is probably all I want (the 10-20 objects are all radar/sensor). I have never used ghost thingy before.
off-topic : It is lucky that this forum has you.
- Wed Dec 27, 2017 2:18 am
- Forum: General Bullet Physics Support and Feedback
- Topic: performDiscreteCollisionDetection (update manifold) for only a few bodies (ghost?)
- Replies: 9
- Views: 8456
performDiscreteCollisionDetection (update manifold) for only a few bodies (ghost?)
I have a loop like :- btDiscreteDynamicsWorld_instance->stepSimulation(......); //has 1000 bodies (20% CPU) add / change position of 10-20 btRigidbody; btDiscreteDynamicsWorld_instance->performDiscreteCollisionDetection(); //<-- slow (10% CPU) iterating btPersistentManifold for collision callback; T...
- Mon Dec 04, 2017 1:54 am
- Forum: General Bullet Physics Support and Feedback
- Topic: "Real-Time Physics Simulation Forum ⢠", pls move, I can't c
- Replies: 3
- Views: 5025
Re: "Real-Time Physics Simulation Forum • ", pls move, I can
I couldn’t agree more. We need it now!
- Tue Nov 21, 2017 12:38 pm
- Forum: General Bullet Physics Support and Feedback
- Topic: Get linear velocity at non-central point on a rigid body?
- Replies: 2
- Views: 15114
Re: Get linear velocity at non-central point on a rigid body
I totally encapsulated Bullet, and coded such functions myself.
It is not convenient, but it works.
getVelocity_relativeToCM_worldAxis(Vector3 positionRelativeToCM);
getVelocity_relativeToCM_shapeAxis(Vector3 positionRelativeToCM);
getVelocity_absolutePosition_worldAxis(Vector3 worldPosition);
It is not convenient, but it works.
getVelocity_relativeToCM_worldAxis(Vector3 positionRelativeToCM);
getVelocity_relativeToCM_shapeAxis(Vector3 positionRelativeToCM);
getVelocity_absolutePosition_worldAxis(Vector3 worldPosition);
- Mon Nov 06, 2017 10:05 am
- Forum: PyBullet Support and Feedback
- Topic: Questions about pybullet use in videogame
- Replies: 4
- Views: 7225
Re: Questions about pybullet use in videogame
Because no one answer ...
I am pretty sure that C++ Bullet is faster than its derivatives.
In practice, especially game, C++ itself is generally faster than python.
It is a reason that I lack knowledge to answer most of your questions.
I am pretty sure that C++ Bullet is faster than its derivatives.
In practice, especially game, C++ itself is generally faster than python.
It is a reason that I lack knowledge to answer most of your questions.
- Sat Sep 16, 2017 2:01 am
- Forum: General Bullet Physics Support and Feedback
- Topic: [solved] scale world 100x -> performance increase 3x
- Replies: 3
- Views: 4780
Re: scale the world up 100x -> performance increase 3x
Thank drleviathan. This is a very reasonable guess.
- Thu Sep 14, 2017 6:53 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Bullet stress test with 5K dynamic cubes
- Replies: 3
- Views: 23048
Bullet stress test with 5K dynamic cubes
I am trying to encapsulate Bullet to my ECS game engine. After some test, I can simulate 2000 cubes, dropped randomly on a 2D static plane. Cubes rarely touch each other. With rendering + my engine cost, in PC, I get :- >80 fps in normal case 50 fps in the worst case (a brief period that all cubes s...
- Thu Sep 07, 2017 11:34 am
- Forum: General Bullet Physics Support and Feedback
- Topic: [solved] scale world 100x -> performance increase 3x
- Replies: 3
- Views: 4780
[solved] scale world 100x -> performance increase 3x
It is surprising that just scale every thing make so much difference in performance. :shock: First Experiment I created a scene with 1,000 cubes. Cube's size = 0.01f They scattered around a plane size = 5*5 (w*h) I got 20fps. The profile result states that Bullet Physics is the bottleneck. Second Ex...
- Sun May 28, 2017 10:21 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Recommended way for predicting the collision?
- Replies: 2
- Views: 6180
Re: Recommended way for predicting the collision?
I would like to know it too.
You may be interested in :-
- http://bulletphysics.org/Bullet/phpBB3/ ... php?t=9692.
- http://bulletphysics.org/Bullet/phpBB3/ ... php?t=4328
- http://www.bulletphysics.org/Bullet/php ... f=4&t=2794
You may be interested in :-
- http://bulletphysics.org/Bullet/phpBB3/ ... php?t=9692.
- http://bulletphysics.org/Bullet/phpBB3/ ... php?t=4328
- http://www.bulletphysics.org/Bullet/php ... f=4&t=2794
- Sun May 14, 2017 4:19 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Trouble setting up Bullet Physics in Visual Studio 2015
- Replies: 13
- Views: 31313
Re: Trouble setting up Bullet Physics in Visual Studio 2015
As a reference, this is the page Anthrax11 mentioned (thank for editing it) :-
http://bulletphysics.org/mediawiki-1.5. ... om_scratch
http://bulletphysics.org/mediawiki-1.5. ... om_scratch
- Tue Apr 18, 2017 2:59 am
- Forum: General Bullet Physics Support and Feedback
- Topic: Scalling Bullet physics
- Replies: 2
- Views: 5731
Re: Scalling Bullet physics
It is a known limitation of Bullet. setLocalScaling is not a cure.
I agree with aviator : you have to manually swap the body.
I agree with aviator : you have to manually swap the body.
- Tue Apr 18, 2017 2:54 am
- Forum: General Bullet Physics Support and Feedback
- Topic: a lot of constraint connected together -> explode
- Replies: 0
- Views: 3189
a lot of constraint connected together -> explode
I have created many bodies with equal mass + constraint like this :- http://i.imgur.com/aaWhPsw.png ^ Image shows 401 chunk of body. 400 bodies are constraint-ed with a single body at the center. All bodies has equal mass. When I change the hook position e.g. bulletFixedConstraint->getFrameOffsetA()...