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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What are the best bullet collision detection methods for FPS games? [duplicate]

Bullets are too fast and can be represented as points. Common collision detection methods, like the ones using bounding volumes, may not be suitable. What would be the best for this work. Edit: this ...
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16 views

Problem with automatic ragdoll shape generation using Bullet

I'm trying to automatically generate ragdoll colliders (for now, box colliders) from my mesh. First of all, I specify the body parts like so: ...
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9 views

Update constraint pivot position in world space in Bullet Physics

The task is: we have N rigid bodies connected with each other by point-to-point constraint. In every frame we have new position of point where first rigid should be attached in world space. How to ...
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1answer
90 views

Bullet: No Bouncing off the walls

I'm using Bullet Physics for Collision Detection in a first person game. The collision basically work fine, I cannot walk through objects. But if I walk against the wall and release the key I get ...
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1answer
22 views

Bullet: Apply any Transformation to RigidBody?

I'm using Bullet for CollisionDetection. I load a scene from a Collada-File using Assimp. Let's say I want to give every object in the scene a RigidBody with a box as CollisionShape. Right now I first ...
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2answers
126 views

Gravity too weak

I am using Bullet Physics and the gravity in my world seems to be too weak. This means that items fall too slowly and general values don't make as much sense as they should. While I know that ...
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48 views

JBullet is acting weird, what is causing these 'floating' rigidbodies?

I've been working on a 3D game engine in Java for a school project. The game engine had scenes containing game objects, these game objects contain components defining the behavior of each object. I'm ...
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1answer
42 views

BulletPhysics ship rotation

First of all, I'm a beginner in game physics, and I think this is a relatively easy problem that I'm not grasping. Short Version: I have a box(representing a ship on water) going forward with a ...
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19 views

JBullet & LWJGL Rendering objects with jbullet transform

I tried to render objects with jbullet matrix transform. Its something like that: get float array where is stored matrix then put it to floatbuffer and load to Matrix4f using load() function. Use ...
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4answers
426 views

Should the bullet trajectory calculated by server or by client? [duplicate]

In a FPS game like Battlefield or Arma, when playing online, should the bullet trajectory be calculated by the server or by the client?
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1answer
96 views

Bullet Physics: Difference between Motion State and World Transform

In Bullet Physics, when I create a new btRigidBody, one of the parameters passed to the constructor is the btMotionState, which defines the initial pose of the body. However, if I then later want to ...
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30 views

How to make btSoftBody and btMultiBody coexist in one bullet physics world?

I followed Featherstone demo in Bullet Physics SDK, and SoftBody demo, I succeded to make them work in Irrlicht but, the Featherstone demo needs btMultiBodyWorld and the Softbody needs ...
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71 views

Bullet Physics: Applying a force at the point of collision

Suppose I want to simulate some kind of gripper with two "fingers" (such as pair of pliers, or two-fingered robot hand), picking up an object from the ground. Both the gripper and the object are ...
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1answer
73 views

Bullet Physics Collision is Not Detected

I have created two btConvexTriangleMeshShape objects. One is a cube of size (0.1 x 0.1 x 0.1), and the other is is a plane of size (1.0, 0.1, 1.0). The plane is static, and the cube is dynamic, and ...
6
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1answer
195 views

Why do Physics Engines use collision margins?

When using a physics engine in a game (such as Bullet), you usually need to define a collision margin for each object. I'm a beginner to game development, and I don't understand the purpose of a ...
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1answer
52 views

how to set in vector float x y coordinates [closed]

i am use eclipse java android i am try to projectile trajectory in my game like angry birds example here ...
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1answer
100 views

Bullet Physics / OpenGL Meshes Not Colliding

This is for a school project, and I'm having a bit of trouble with Bullet acting strangely. I have an OpenGL project with Bullet Physics library working with Assimp model loaders and Magick++ ...
2
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1answer
140 views

Is restitution the wrong value, to make bouncing objects?

I have been experimenting with Bullet. Specifically I was modifying the Hello World tutorial, to make the ball bouncing. The first thing I noticed is, that I need to set both the restitution of the ...
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0answers
232 views

Java 3D collision detection with JBullet

So I have spent a long time trying to work on a collision detection system from scratch for own game engine and came up fruitless due to lack of time. Finally I decided to try to use Jbullet to try to ...
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55 views

Simulate a velocity sensor attached to a softbody node with bullet physics

I try to implement a virtual three-axis velocity sensor attached to a softbody node. The node already provides it's global position, normal and velocity, but how to calculate it's local velocity to ...
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1answer
43 views

Bullet Physic: Stack transformations on body after adding

How can I stack multiple transformations on a body? I mean... Rotate, translate and then rotate again? If I understood, a transformation on a rigid body can be made like this: btTransform ...
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1answer
100 views

issue with ray/physics collision detection

All, I am trying to pick object using ray collision and bullet physics I am initializing my projection and view matrix only once, here is the code projectionMatrix = glm::perspective(90.0f, 4.0f ...
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0answers
115 views

Simple Bullet Physics Collision Detection

I've been looking into bullet physics a lot here lately to handle my collision detection. I was using XNA collision but once I started to implement momentum into my physics simulation true and false ...
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33 views

Bullet btGImpactCollisionAlgorithm

I have a question about Bullet and in particular GImpact. When, the collisiontestpair(a, b) is called where GImpact pair check algo will be called on the btGImpactMeshShape, does it do a AABB tree ...
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0answers
7 views

doll lift by applying force and gravity force [duplicate]

Iwant to lift the doll by applying force to box rigidbody. Doll has a few rigidbody and constraint. Then set gravity ZERO, don't work well. please tell me!
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1answer
348 views

Bullet Physics - Collision not working when moving btBvhTriangleMeshShape

I have a robot (btTriangleMeshShape for each component) and a chain of boxes used as a cable, which is anchored on two components of the robot. I want to rotate a robot component and when this ...
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1answer
254 views

How to Load a Level for use with the Bullet Physics Library

I am trying to use a level in .obj format loaded with Assimp to generate a btBvhTriangleMeshShape to use with the Bullet physics library. I can successfully load btConvexHullShapes as well ...
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1answer
809 views

unity3d - Fire bullet using AddForce is very slow

This is a top-down view but in 3D coordinates, I would like to instantiate and fire a bullet from the player's gun. This script is on a spawner object at the end of the barrel. void Fire () { ...
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1answer
117 views

Improving performance for flocking behavior?

I have a game that I am trying to make. It is a twin-stick shooter that I want to design to have a LOT (Up to 500) of enemies on the screen. The game's base design comes from that of Geometry Wars, ...
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0answers
116 views

server/client architecture, how to combine physics data, scene graph and database over the network?

I'm writting a C++ server and a C++ client for a rpg game. The client is using OpenSceneGraph for rendering the 3D. RakNet is used for communication between the client and server. At this time, the ...
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23 views

Launching projectile from a “canon” [duplicate]

I'm working on "Scorched earth"-like game just for learning purpose. I can't figure out how to launch the projectile from my tank's position, with a power of X ([0,100]),at an angle of Y ([-180,180]). ...
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1answer
170 views

Java JBullet Mesh collsion problem

I have a problem with JBullet mesh collsion. Everything works fine when I create a mesh from my object without scaling, but the problem starts when I want to scale the object. I also tried scaling in ...
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0answers
167 views

Projectile Delta Movement

I'm running into an issue where I can't get the Projectiles to travel in the right direction, I'll admit my trig is a little rusty, anyone know how below might be improved? I am trying to get the ...
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1answer
752 views

Bullet Physics - scaling

I have added Bullet to my game engine. So far I am using translation and rotation, and it works fine. But now, I want to scale my geometry (eg. user can drink some potion an became small :-)). I am ...
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303 views

Trying to bounce a box with a plane using bullet physics

I'm trying to simulate a box that bounces with a plane and I'm beginner with bullet physics. I created a plane (box) and and a box that is falling. The problem is the ball is stalled while colliding ...
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1answer
92 views

Understanding HingeConstraint in jBullet

I'm using the java port of BulletPhysics engine jBullet. I'd like to make a joints between 2 triangles so that one edge of the first and one edge of the seconds act like a hinge. But I don't ...
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1answer
94 views

Bullet pointer becoming zero [closed]

I am currently trying to implement the Bullet physics into my game project. However, when i add some rigid bodies to the scene, i occasionally get an error in btDbvtBroadphase.cpp at the line ...
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1answer
197 views

How can I get a 4x4 matrix from a bullet quaternion?

I'm trying to make a game using JavaScript with Ammo.js ( an implementation of bullet ) and Sylvester to do my matrix maths. The problem is I don't know how to turn the WXYZ that bullet gives into the ...
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1answer
440 views

In a TPS, how to aim bullets to the direction the camera is pointing, but make the shooting from the player?

(In C#/XNA.) I mean, I can't find an answer nowhere. I'm trying to learn how to make a Third Person Shooter, especially like the one I found in a game called "M.A.R.S.", from Epic Games. I don't want ...
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1answer
241 views

Multiplayer and creeps (NPC enemies): how to compute bullet hits given the lag?

We are making a multiplayer co-op game, where players will shoot not each other but AI enemies (creeps), controlled by the game. The chosen implementation is client-server with an authoritative ...
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1answer
587 views

Friction not working for Vehicle in BulletPhysics

I am creating a vehicle using bullet-physics engine (v 2.82). I created a ground ( btBoxShape ), a box and a vehicle (following the demo). But friction between ground and vehicle wheels seems not ...
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2answers
163 views

Libgdx, find Vector3 direction

I am using Libgdx along with Bullet physics. I have a vehicle moving. I would like to use a ray from the vehicles origin and in the vehicles forward direction. How can I create the forward Vector3 ...
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1answer
300 views

Bullet - objects falling through

I have problem with bullet collisions. You can see problem on this video (around 0:18): http://goo.gl/DiVP8l Objects are "embeded" inside vertical bars - that is not correct - they should be ...
2
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2answers
1k views

What torque should I apply in Bullet to maintain a vertical orientation?

I have a RigidBody in Bullet. Each frame, I want to apply torque to correct its orientation toward an upright position (i.e. near-zero pitch and roll). I know its angular velocity and orientation. ...
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1answer
173 views

Irregular oval collision detection

I am using a physics library based on the Bullet physics engine. How do I create an egg shaped object or a cylinder where the width differs from the depth (i.e. with an oval shape)? I'm not looking ...
2
votes
1answer
648 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 ...
1
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1answer
528 views

Bullet 3D Physics Objects Not Rotating?

So I've got Bullet 3D controlling the motion of objects rendered with DirectX. In the clipping below I've got 2 identical rectangles & 5 balls. The lowest rectangle has a mass of 0 and doesn't ...
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2answers
1k views

How to implement a simple bullet trajectory

I searched and searched and although it's a fair simple question, I don't find the proper answer but general ideas (which I already have). I have a top-down game and I want to implement a gun which ...
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0answers
60 views

Bullet Physics ConvexDecomposition?

I've looked at Bullet Physics ConvexComposition Demo and would like to implement that in my game but the code is so undescriptive and it's hard to understand what is going on. Would any of you people ...
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1answer
385 views

Using Bullet physics engine to find the moment of object contact before penetration

I would like to use Bullet Physics engine to simulate the objects in 3D world. One of the objects in the world will move using the position from 3D mouse control. I will call it "Mouse Object" and ...