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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1answer
847 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 ...
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1answer
43 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
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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
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
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1answer
82 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 ...
2
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0answers
273 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
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1answer
689 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
709 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
928 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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1answer
2k 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
689 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
374 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
623 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
76 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
245 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 ...
1
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1answer
102 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
658 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
208 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
153 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
696 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
676 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
375 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
1k 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
51 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
410 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
422 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
838 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
367 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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1answer
45 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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0answers
29 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
104 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
83 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
428 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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0answers
54 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
501 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
705 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
442 views

3D game editor with C++ support and Bullet Physics [closed]

I am very new to game development and hence the question. Is there any open-source game editor that uses Bullet Physics engine with C++ code edit support.I have read about blender but it allows python ...
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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
404 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 ...
1
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1answer
913 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
148 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 ...
0
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1answer
197 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 ...
0
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1answer
611 views

How to use Bullet physics with Entity Component Systems?

I have an Entity Component system and I want to have a Physics Component that would add the given object to the physics simulation. My problem arises because the Bullet API requires me to add each ...
0
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1answer
261 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 ...
0
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1answer
753 views

Allegro Game Won't Fire 2D Projectile

To begin with I am developing a PSP application so I have no clue how to debug a PSP application. That doesn't mean I do not know how debug period. Anyway, when I run the game everything runs fine but ...
0
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1answer
41 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 ...
0
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1answer
532 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 ...
0
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2answers
317 views

Best collision shape for rooms

I'm wondering what is the most efficient collision shape to use with APIs like Bullet or Havok for rooms/interiors. Rooms tend to be boxes but are concave since the normals point inward which means no ...
0
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2answers
681 views

Distance between two objects?

We are trying to determine the distance (a scalar, double) between two objects' surfaces in Bullet. We are new to the Bullet engine, and we've been looking into the demo projects, but couldn't find ...