Bullet is a professional, free 3D Game Multiphysics Library that provides state of the art collision detection, soft body and rigid body dynamics.

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14
votes
1answer
840 views

What are pros and cons of Voronoi shatter?

I have seen some Voronoi shatter videos on Youtube. What is your experience with it? What are the pros and cons in time complexity, resource complexity, implementation difficulty...? Does it ...
12
votes
4answers
5k views

2D tower defense - A bullet to an enemy

I'm trying to find a good solution for a bullet to hit the enemy. The game is 2D tower defense, the tower is supposed to shoot a bullet and hit the enemy guaranteed. I tried this solution - ...
8
votes
3answers
3k views

How do I implement a Bullet Physics CollisionObject that represents my cube like terrain?

I've successfully integrated the Bullet Physics library into my entity/component system. Entities can collide with each other. Now I need to enable them to collide with the terrain, which is finite ...
8
votes
2answers
3k views

How to disable Y-axis movement in the Bullet physics engine

I want to create an object than only moves along the the X and Z axes, while keeping the Y-axis disabled (it's like movement in 2D, and the object wont fall down). I'm currently using a 6 dof ...
8
votes
1answer
481 views

How can I extend btCollisionAlgorithm to enable collision with a voxel terrain?

I am using Bullet, and am attempting to make a collision algorithm that generates contact points off of a cube-based terrain along with the appropriate collision response. I also plan to extend this ...
7
votes
2answers
4k views

Is it worth it to use Bullet for 2D physics instead of Box2D for the sake of learning Bullet?

There isn't much more to the question. I'm not concerned about overhead, as I'm sure they are both fine for my purposes. Basically, I am familiar with Box2D concepts because of the Farseer Physics ...
7
votes
2answers
4k views

How would I move a character In an RPG with Bullet Physics/Ogre3D?

lately I have been having problems with moving my character in my Ogre3D game. Basically I am moving the character with bullet's RigidBody->translate() function, but when doing so and bumping into ...
7
votes
3answers
2k views

Physics not synchronizing correctly over the network when using Bullet

I'm trying to implement a client/server physics system using Bullet however I'm having problems getting things to sync up. I've implemented a custom motion state which reads and writes the transform ...
6
votes
5answers
1k views

How to save and restore Bullet Physics state?

I'm looking for information on how to save the runtime state of rigid bodies with Bullet Physics. Most of my world consists of static objects, but I have a few dynamic and kinematic objects as well. I ...
6
votes
1answer
1k views

Bullet Physics - Casting a ray straight down from a rigid body (first person camera)

I've implemented a first person camera using Bullet--it's a rigid body with a capsule shape. I've only been using Bullet for a few days and physics engines are new to me. I use ...
6
votes
3answers
1k views

Jitter during wall collisions with Bullet Physics: contact/penetration tolerance?

I use the bullet physics engine through Panda3d. My scene is still very simple, think 'Wolfenstein3d': tile-based, walls are solid cubes. I expect walls to block the player, and I expect the player ...
6
votes
1answer
1k views

How can I get my meshes to work with Bullet Physics?

The problem is that I'm trying to use my meshes with Bullet Physics for the collision part of my game. When I attempted doing this method with my GLM(model loading library by nate robins) model, I ...
5
votes
1answer
2k views

Should I use procedural animation? [closed]

I have started to make a fantasy 3d fps swordplay game and I want to add animations. I don't want to animate everything by hand because it would take a lot of time, so I decided to use procedural ...
5
votes
1answer
3k views

how get collision callback of two specific objects using bullet physics?

I have got problem implementing collision callback into my project. I would like to have detection between two specific objects. I have got normall collision but I want one object to stop or change ...
5
votes
1answer
772 views

Bullet Physics implementing custom MotionState class [closed]

I'm trying to make my engine's camera a kinematic rigid body that can collide into other rigid bodies. I've overridden the btMotionState class and implemented setKinematicPos which updates the motion ...
4
votes
2answers
889 views

Simulating the effects of wind

I am developing a mobile game for Android. It is a 3D jumping game (like ski jump) where wind plays a important role so i need to simulate it. How could I achieve this? The game uses libgdx for ...
4
votes
1answer
816 views

Bullet physics debug drawing not working

Background I am following on from this question, which isn't answered yet. Basically I have a cube and a UVSphere in my scene, with UVSphere on the top of the cube without touching the cube. Both ...
4
votes
2answers
415 views

Intersection points of plane set forming convex hull

Mostly looking for a nudge in the right direction here. Given a set of planes (defined as a normal and distance from origin) that form a convex hull, I would like to find the intersection points that ...
3
votes
2answers
363 views

How to account for speed of the vehicle when shooting shells from it?

I'm developing a simple 3D ship game using libgdx and bullet. When a user taps the mouse I create a new shell object and send it in the direction of the mouse click. However, if the user has tapped ...
3
votes
1answer
7k views

How do I integrate bullet physics into my game?

I downloaded the release file found here, but I'm just not sure where to start. In my game I have a number of oblongs and a sphere, I want all of these to collide with one another. (They all have ...
3
votes
2answers
846 views

Can I change shape of a rigid body after it created in Bullet3D?

I'm beginning Bullet3D. Can I change collision shape of a rigid body after it created? A rigid body accepts a collision shape when it's creating, but it's hard to find options changes the collision ...
3
votes
2answers
6k views

Ogre 3d and bullet physics interaction

I have been playing around with Ogre3d and trying to integrate bullet physics. I have previously somewhat successfully got this functionality working with irrlicht and bullet and I am trying to base ...
3
votes
1answer
341 views

Moving the jBullet collision body to with the player object

I am trying to update the location of the rigid body for a player class, as my player moves around I would like the collision body to also move with the player object (currently represented as a ...
3
votes
1answer
1k views

Create bullet physics rigid body along the vertices of a blender model

I am working on my first 3D game, for iphone, and I am using Blender to create models, Cocos3D game engine and Bullet for physics simulation. I am trying to learn the use of physics engine. What I ...
3
votes
2answers
472 views

Choosing a correct collisionshape for a voxel engine

I am building a voxel engine on Ogre with bullet as a physics engine. I separated my blocks into chunks to help batch together render calls. At the moment, each chunk's physics is handled by a ...
3
votes
1answer
2k views

How can I enable CCD in Bullet Physics?

How can I enable Continuous Collision Detection (CCD) in Bullet Physics?
3
votes
1answer
472 views

Create a physics body with hole : bullet physics

I am writing an iOS game, using bullet for physics, blender to create models, cocos3d as the game engine. I have a model like this Basically there is a plane, with a hole, and a UVSphere. Both were ...
3
votes
1answer
214 views

How do I run a callback when all objects have stopped moving?

I'm using Bullet and want to take some action once all objects in a dynamic world have reached 0 velocity (or at least a value that's very close). I was trying to iterate over all of them all the ...
3
votes
0answers
402 views

Setting Orientation of Character in Bullet/Ogre [closed]

I've been suffering from an issue regarding the implementation of orienting characters in a game I'm implementing using Ogre3D and Bullet physics. What I have: A Direction Vector that the character ...
3
votes
0answers
302 views

How can I make bodies that do not stick to the wall in Bullet Physics? [duplicate]

Possible Duplicate: Physics engine recommendation which can simulate pool game correctly? I made a Billiards scene with Bullet Physics, but I've got a problem. When the ball is slowing down ...
2
votes
3answers
2k views

How do I check collision when firing bullet?

I'm currently creating 2D game from top perspective. I'm having problems with bullets. Yes, I currently simulate their movement so user can see them (about 2x ). Moving them with // this is static ...
2
votes
2answers
227 views

Spherical / Relative Gravity

I'm working on an Ogre3D + Bullet project that involves planets in a solar system. For all intents and purposes, I'm looking to give each planet it's own gravity sphere. So far, all I've found are ...
2
votes
2answers
1k views

What is the best way to check if there is overlap between player and static, non-collidable items in bullet physic engine

I'd like to add non collidable objects (eg: power ups, items, ...) in a game world using Bullet Physics Engine and to know if there is collision between player and them. Some info : there is a lot ...
2
votes
1answer
153 views

How can I use imprecise accelerometer data for controls?

I want to rotate an object with respect to the phone's position. I use the accelerometer output to detect orientation: float roll = Gdx.input.getRoll(); float pitch = Gdx.input.getPitch(); float ...
2
votes
2answers
936 views

How to load a terrain of connected caves into bullet-phisics engine?

I have a terrain that can not be represented as height map. Say a mountain with caves. I have it in one large .obj file. How do I load such a terrain into bullet-phisics engine? Or I shall generate ...
2
votes
2answers
767 views

Efficient Bullet Firing Class

I've been struggling with this for a while. I have been trying to create a bullet pool class for a game I have made that doesn't cause a significant fps drop. I have tried creating a bullet pool ...
2
votes
1answer
2k views

Object rotating error in Bullet Physics with OpenGL

I have got some problem in my OpenGL game. I am using bullet physics and I want to achive quite simple effect - I want one object (a sphere) to roll and hit another (box) which will fall down. I have ...
2
votes
1answer
655 views

Can Bullet Physics (or another 3d physics engine) use callbacks in my engine to check static geometry?

I'm wondering if it's possible to use or hack Bullet 3d Physics (or another free 3D physics engine) so that I don't need to "import" my static geometry into Bullet - instead I want to do it the other ...
2
votes
1answer
372 views

Conceptual - What is the optimal way to combine steering behaviors with rigid body physics?

I am working on a simple 3D space simulator that makes use of the Bullet physics engine. The spaceships are rigid bodies that have a mass and hitbox so that they can be considered for collisions. At ...
2
votes
1answer
124 views

What are the parameters for btHingeConstraint::setLimit

What does each parameter in btHingeConstraint::setLimit do to the hinge constraint? void btHingeConstraint::setLimit ( btScalar low, btScalar high, btScalar _softness = ...
2
votes
1answer
741 views

Bullet Physic: Transform body after adding

I would like to transform a rigidbody after adding it to the btDiscreteDynamicsWorld. When I use the CF_KINEMATIC_OBJECT flag I am able to transform it but it's static (no collision response/gravity). ...
2
votes
1answer
1k views

Bullet Physics Terrain

Im trying to Load an RGB image (.BMP) into bullet's btHeightfieldTerrainShape Im using a loader that creates a openGL height map, it stores the data in a vector float, but I cant get the ...
2
votes
2answers
2k views

How do you setup the Irrlicht and Bullet engines for Android development?

I have begun researching graphics and physics engines to use for an Android 3d game that I would like to make. While researching I stumbled across this page where he talks about how you can use the ...
2
votes
1answer
485 views

bullet character controller sliding down any slope gradient

I've been experimenting with the btKinematicCharacterController. I've seen very old complaints that it has issues but I can't find anything recent stating that these issues remain (and nobody ever ...
2
votes
1answer
42 views

Stick 2 btRigidBodies together

I have a platform with btBoxShape as shape, and I want to rotate it every certain amount of time to simulate a rotating platform. Right now I rotate it with Ogre (my rendering engine) and use a ...
2
votes
1answer
976 views

How can I exclude some rigid body from rayTest in Bullet Physics?

I'm trying to picking some object with rayTest method of BulletPhysics. The problem is my stage is surrounded with walls (btStaticPlane) and the target objects (btSphereShape) are in there. And I'm ...
2
votes
2answers
2k views

How would I use GLM for Bullet Physics?

Right now im working on my c++ game, and im having alot of trouble using GLM and Bullet Physics to create my world correctly. The main problem is that when i export my physics with Blenderv2.57, and ...
2
votes
0answers
134 views

Quaternion - rotating rigidBody to particular angle over time

Using Bullet Physics. There's a rigid body that is rotated. For some delta-time I need to rotate that body to have rotation of (0, y, 0) - keep the old y value rotation but reset x and z. The ...
2
votes
1answer
248 views

Bullet physics weird behavior . Jittering and drifting with btBoxShape

I'm working with bullet physics, and I have some weird behavior. What's happening is that as a simple test, I'm dropping a simple box onto a plane from 100 units. It's important to note that the ...
2
votes
0answers
155 views

Bullet btGeneric6DofConstraint and btGeneric6DofSpringConstraint constructor arguments

I have a very simple (and maybe too primitive to post here but I’ll try anyway :P) question about Bullet constraints. What are arguments const btTransform &frameInA, const btTransform ...