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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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). ...
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1answer
2k 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 ...
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1answer
3k 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 ...
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1answer
44 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 ...
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1answer
1k 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 ...
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2answers
3k 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
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1answer
175 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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306 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 ...
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1answer
768 views

Bullet physics: how to make a soft body “static” (kind of)?

I'm fairly new to Bullet and started using it a week ago. I mainly played with rigid bodies and everything works as expected but now that I also need to add soft bodies into my simulation, things got ...
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1answer
757 views

What algorithms can I use for bullet movement toward the enemy?

I'm developing 2D strategy game. There are weapons that shoot at enemies. From what I've read in this, this, this and this post I think that I need linear algebra, but I don't really understand what ...
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2answers
1k views

LibGDX - draw bullet physics bounding box

I am very new to game development and I am trying to debug my 3d collision bounds. Could somebody give me an example on how to draw the collision bounds of an object in libGDX? I assume it has ...
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2answers
131 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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1answer
890 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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1answer
3k views

Detect two specific objects collision with bullet physics

I have got some problem with defining collision between objects in my game using bullet physics. I know that objects are colliding with each other simultaneously and I don't have to do anything more. ...
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1answer
710 views

Calculating bullet travel knowing coordinates and radian

I have a player sprite that has a x and y coordinate and also a radian. The radian determines which way the sprite faces in a top-down game interface. In this case, the radian points from the player ...
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1answer
3k views

Best 3D Physics Engine to use with Ogre [closed]

I am looking for a good physics engine to use with an Ogre game I'm writing. I would prefer for it to be free, open source, mature, simple to use, easy to learn, and flexible. I'm currently thinking ...
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1answer
477 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
671 views

Rotating a cube using jBullet collisions

How would one go about rotating/flipping a cube with the physics of jBullet? Here is my Draw method for my cube object: public void Draw() { // center point posX, posY, posZ float ...
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1answer
117 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++ ...
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1answer
406 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 happens,...
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1answer
123 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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2answers
710 views

How to correctly create bullet rigid from custom .mesh in Ogre?

Being new to 3d programming and bullet physics in particular, I am wondering how a 3d model or the mesh generated out of it effects the accuracy of bullet physics simulation. I have written a ...
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1answer
286 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
182 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 ...
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1answer
825 views

How to draw a plane equivalent to a given btStaticPlaneShape using OpenGL

With all other shapes in bullet, you can easily get the transform from the MotionState which holds the origin, the scale, and the rotation. There seems to be no way to get the same information about a ...
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2answers
780 views

Jump without bouncing in physics engine

I am using Ogre3D as my rendering API, and OgreBullet as my physics engine. I have an test entity that when the y part of the velocity is 0 and spacebar is pressed, the velocity changes to, lets say: ...
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1answer
384 views

Need help with a complex 3d scene (using Ogre and bullet)

In my setup there is a box with a hole on one side, and a freely movable "stick" (or bar, tube). This stick can be inserted/moved through the hole into the box. This hole is exactly as wide as the ...
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2answers
2k views

First person camera with Bullet Physics

Before integrating the Bullet Physics, the camera worked fine. But instead of using my own simple struct for transform data, I use rigid body structs provided by the physics library now. There are ...
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1answer
56 views

How to squash stretch the Bounding box so as to get Good Physics effect

I have Surrounded a game Object with a rectangular Box and applied Physics properties to that Box so that load on the computation gets reduced. But i have a problem, whenever in animation if the Game ...
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1answer
412 views

Roughly how many rigid bodies can I expect to have interacting in Bullet?

On my Phenom II desktop machine (about 3 years old) with 8GB of RAM, it seems that I can only throw around a hundred or two boxes before it starts to go slow. I'm using the built-in DbvtBroadphase. ...
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1answer
446 views

3D/perspective Top down shooter bullet issues

I'm developing a top-down shooter with multiple levels (ground for ground units, middle level for buildings, top level for air unity). The problem is the collision. Though I can make the collider ...
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2answers
942 views

Bullet physics in python and pygame

I am programming a 2D sidescroller in python and pygame and am having trouble making a bullet go farther than just farther than the player. The bullet travels straight to the ground after i fire it. ...
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1answer
372 views

How would I setup the Environment Variables for BulletPhysics?

I am using Bullet Physics v2.78. And Im trying to build this library to be used for ogrebullet. The main problem is that Im getting errors trying to find the Bullet Directory. Im wondering if maybe ...
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25 views

Retreive 3d World Map coordinates from touch/click input with LIBGDX?

Problem: I am trying to create an RTS style interaction. I want to be able to click on the map and have characters move to the click location. I haven't been able to figure this out, even after ...
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0answers
35 views

Soft body plasticity using Bullet Physics

I made this post on the Bullet forum(link), but the forum is slow so I'm just copying the text from there. Hello, I'm currently working on a game and I want to make certain surfaces of the game ...
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1answer
51 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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0answers
83 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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269 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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0answers
35 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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125 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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1answer
95 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
569 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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62 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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0answers
555 views

Bullet Physics Simulation Running Slow

I'm in the process of converting my game engine from java which used the LWJGL and JBullet to c++. However, when I was implementing Bullet physics my simple simulation of a box dropping from specified ...
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0answers
727 views

What is the best way to implement collision detection using Bullet physics engine and a track generated from a curve?

I am developing a small racing gam, the track is generated from a curve. As said above, the track is generated, but not infinite. The track of one level could fit with no problem in memory and will ...
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0answers
119 views

colliding btRigidBody objects behave strangely when moving slowly

I'm trying to use Bullet Physics in my iOS game. The engine appears to be correctly compiled in that the demos work fine. In my game I have the player's ship and some enemy ships. They're defined as ...
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1answer
412 views

Offset Forward vector of object based on Rotation

I'm using the Bullet 3D physics engine in a iOS application running openGL ES 1.1 Currently I'm accepting info from the gyroscope to allow the user to "look around" a 3d world that follows a bouncing ...
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1answer
973 views

Change collision body position in Bullet Physics Hello World project

I have got stupid and annoying problem in my app. I am using bullet physics and I've started with hello world example on wiki: http://bulletphysics.org/mediawiki-1.5.8/index.php/Hello_World There is ...
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1answer
18 views

Bullet Physics Applying Torques Effects not noticeable

I am applying torques to a rag doll in order to make it move/walk. For some reason, I am unable to view any effects when I use a call to rigidbody to apply torques even though these torques are ...
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1answer
182 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 ...