Box2D is an open-source rigid-body 2D physics simulation library for games, written in C++, with ports in various languages

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Soft Body Collision with Box2d (libGDX)

I've made a few classes to create soft body objects in libGDX using Box2D (specifically a circle and rectangle similar to these links). The objects are constructed of a number of circle shaped Box2D ...
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Drawing the box2D rectangles

i'm using SDL2.0/OpenGL + Box2D with C++ to learn some stuff about games, so i created two rectangles bodies: a small box(dynamic) wich will fall into the second body: the ground(static), i draw them ...
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Box2d java contact point reference changes after collision

I am trying to hold the contacts made during a collision in an array list. After I add n amount of contacts, when I try to retrieve them later on, they point to the last contact made in the world. ...
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LibGDX: Issue with unitScale for Tiled and Box2D

I've got the following: I use a TiledMap (loaded from a .tmx), each tile 32x32 pixels in size and generate the Box2D bodies for collision from the TiledMap's ObjectLayer. That all works fine, no ...
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Why is my Box2D Body only colliding with one type of Object after a new level has been built?

So developing for an android mobile game, using Android Studio and developing for the API 17, with Box2D implemented. FIRST LEVEL For some reason, one the first level everything is running okay: ...
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dynamic body jumping out of water object

In my game I have my main object, a jetski, which will dive down into water, when the screen is touched. I managed to code the jetski diving down, with Box2d and some buoyancy forces. But when the ...
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applyForce as long as display is pressed

In my project I have my main character body. I want it to move down on the y-axis as long as the screen is pressed. I tried it with public boolean touchUp(int screenX, int screenY, int pointer, int ...
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In Box2D, what exactly does a fixture represent?

In Box2dWeb, when we create a body we attach a fixture to the body object. We make the shape, friction, restitution and so on by tinkering with the fixture object. So from this can we conclude that ...
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Black screen when launching on phone

I am coding a game in libgdx. While adding the background I used the html module to watch the results fast and easy on my computer. But when I try to see it on my phone I just get a black screen. My ...
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Camera controll in Libgdx

I've a condition in my game where, I want my camera to follow the Player(its a body from Box2d) and in some not. This is the start screen of my game: Now, when i press a button(space) the player ...
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TypeError: R[o5R.F6s] is not a function in changing states in phaser box2d

i build my game using phaser.2.4.3.min.js and phaser.2.2.2.box2d.min.js When trying to change states this error is being raised TypeError: R[o5R.F6s] is not a function and i can't seem to figure out ...
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Why do my game objects jitter when moving the camera?

I'm moving from Qt Widgets' QGraphicsScene to Qt Quick's QQuickItem for rendering my game objects. One of the things this involves is setting up a scene and the view onto that scene, as this was ...
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DynamicBody diving into StaticBody

In my game I want a DynamicBody to dive down into a StaticBody. I set up both bodies. At the moment they are colliding. How can I get my DynamicBody to dive down? Is it going to work with this ...
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38 views

Box2d Coordinate System

In the game I'm trying to code I got to have two bodies. One StaticBody and one DynamicBody. I want to have the DynamicBody on top of the StaticBody. Somehow all I get is this: Is it possible that ...
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Box2d jetski on water

At the moment I am trying to code a 2d game in java, where a jetski is riding on water. If you press on the screen the jetski should dive down and jump back up on release. How do I have to do this in ...
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Viewport and Camera setting

For my first game in LibGDX and Android I got a Problem: I have a background picture which is 2560px * 720px. The screen is 1280 * 720. How do I have to set the viewport and camera in order to get ...
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Collision Detection/Response Issues in Unity

Sprite A: Box Collider 2D and Rigidbody 2D. Sprite B: Box Collider 2D. Both sprites have a Sprites/Default material with Pixel Snap enabled. The textures being used are set to Truecolor Format and ...
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Why are my Hello World Box2D project's collisions off by twice the size of my boxes?

I've been implementing Box2D into my engine but have run into a snag. I decided to rebuild the helloworld project inside of my own engine (it is almost identical), of which I will snip here in a ...
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Movement through forces and impulses

I'm trying to get some decent-looking movement in my game using this tutorial. In the image below... something crazy is going on. What should happen is that the NPC should start on the left side of ...
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libgdx - Check if body is touch

I have some bodies around the screen(Ball[] balls), and I would like to delete them when user touches them. Also, I have an Image as userData of the bodies. I dont want to make a function to all ...
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balloon ligher than air with libgdx, impementation of FixtureDef.density, gravityScale, linearDamping?

I use libGdx/box2d's physic. My intention is to create a balloon filled with helium (a body, what hovers above a surface, if we apply a little force to it - it moves fast but not far, if we push ...
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Marketing PC/Android 2d Physics Game [closed]

I've been working on a game for couple years now, its fairly original, has definite potential within an indie market, and appeal for the masses also. I want to deploy on Android and PC, green-light ...
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How do I query a LibGDX Box2DLights “light” and “dark” regions?

I have lighting implemented using Box2dLight. I want to update/render things inside the player's PointLight area. Stuff in the dark area should not be rendered. How can I find which areas are lit or ...
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133 views

Box2D collision between dynamic body

I'm implementing Box2D for my 2d top down LIBGDX game and i have some struggle with two dynamic body. Currently, my two bodies are created that way : BodyDef bodyDef = new BodyDef(); bodyDef....
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Box2D - Platformer tiled map problem

I'm using C++, Box2D and SFML. I convert a Tiled map to world in my platformer game and I get stuck when I go against a block when I go forward like that : I can use a circle as foot of my ...
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boost/geometry replacement in Java/for the JVM (Destructable Box2D terrain)

I'd like to reimplement https://github.com/seemk/DestructibleBox2D in Java. The main problem is finding an adequate replacement for the boost/geometry library. Any ideas?
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Is GetFixtureA() of b2Contact guaranteed to return the body on which GetContactList() was called?

For example, in the code below, will the assert ever fail? for (const b2ContactEdge *contactEdge = playerPhysicsBody->GetContactList(); contactEdge; contactEdge = contactEdge->next) { ...
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Should I initialize a Box2D World per Level?

I'm using a LevelManager to load Tiled maps in my libGDX game, which stores: Static: final Size of map in Tiles final Size of map in Pixels final Size of an individual tile TiledMap ACTIVE_MAP ...
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Running and Jumping using Box2d and libgdx

.this is my first trial on making a 2d game and currently struglling how to run and jump smoothly. My problem is when the player keep pressing on left or right botton then jump. the player won't jump, ...
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C++ SFML and Box2D: Move world or move player?

I'm currently making a top-down shooter game and it's my first time developing with SFML. I came across and issue and I want to know if there is a better way to solve it. I need to get the "camera" ...
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generate box2d bodies from isometric tiled map

I followed the tutorial here to generate box2d bodies from a tiled map and that worked fine.... for orthogonal tiled maps. Unfortunately isometric maps use their own coordinate system where (0, 0) is ...
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LOVE Physics - Joint Stretching

After asking a similar question yesterday I've come across another problem with using joints in box2D / LOVE and trying to create a weighted chain. Everything is set up as follows, I've tried to ...
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LOVE Physics - Breaking Joint Chains (LUA / Box2D)

Wasn't sure whether to post here or on SO so please move if needed. I've been having a look into the box2D physics API provided by LOVE to try and create a swinging flail or weighted rope but I'm ...
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How to make sure that when two bodies collide, there is only one collision detection on box2d?

I'm using LibGDX with Box2D and, when two bodies collide, the collision is detected multiple times. Here's the code: public void preSolve(Contact contact, Manifold oldManifold) { Body a = contact....
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Which Box2D-like physics engine parameters need pixel conversion?

The official guide does not have any useful details on the matter: http://www.box2d.org/manual.html Position is an obvious one. What about velocity? Density? Anything else? Update: the context is ...
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Box2d Body to follow mouse movement

I am trying a box2d body to rotate following the mouse. Here's an image to clarify what I mean. The red and blue circles are current point of the mouse and the body (of corresponding color) moving/...
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Libgdx Scene2d and Box2d light

Currently I am using scene2d and I want to implement shadows using Box2d light. I want shadows under characters but when I draw something after render() , it draws nothing. For example, in draw() ...
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Box2D No Gravity when moving against wall

I use Box2D in my current project and I have a problem with the gravity.. You can see my problem here: https://www.youtube.com/watch?v=2_kv9LkKwN4&feature=youtu.be when i jump normal everything ...
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Creating a Melee Weapon in Box2D (libGDX)

I am struggling with how to implement a melee weapon that can swing when a key is pressed. I am imagining two different attacks (stab and swing) I have tried creating two fixtures (character + ...
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Use libgdx box2d for dynamically generated top down map

So, I've already found some information on how to use box2d and tiledmap together. Since I want to generate my top down map (100 by 100 tiles), I thought about only using box2d. The tiles would be ...
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Libgdx using Box2d with TiledMap to create collision detection

I'm fairly new to Libgdx and have some good basic knowledge on Java. Right now I am stuck on how to add collision to my TiledMap, I am using the Mapeditor to create the tilemap. I read so many ...
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Sizing a Box2D ground object

I am developing a platformer game using SDL2 for graphics and Box2D for physics. I am currently designing my levels and would like to know if it is better to make the static part of each level (ie: ...
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LibGDX, Box2D , Destroy body into parts [closed]

I am developing a game using libGDX game engine and box2d physics engine. There are asteroids in my game, I want to destroy their bodies randomly and fill with texture. How can I do it?
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Why does physics interpolation give me periodic jumps/flickers?

I have seen this question but it didn't solve the problem. I have followed the same steps as in this article. What I notice in my Android game is that my interpolation alpha (or fraction or ...
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Box2d joints still attached after Explosion simulation

I ported simple Box2d Explosion simulation the function is called once when there is some event with the "Truck Car" the problem is that the Explosion working fine but it looks like when the explosion ...
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What are the steps for creating level in Libgdx with Box2d? [closed]

I have been trying to learn game programming for a week, although I have a good knowledge of programming. I don't understand some steps of game design. I'm recently working to clone the iSlash game.I'...
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Good collision resolving mechanism

In my game i have plenty of objects that can collide. Literally, most of them can collide with each other.The problem I'm facing is that i can't come up with some good collision resolving way. How can ...
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Calculating density of an object

I'm using Box2D for physics in my game, and one of the things it needs to know when creating a shape for a physics body is the shape's density. I had no idea what value I should specify, so I went to ...
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How to convert pixels to meters in Box2d with Cocos2d-x 3.5?

I am using Cocos2d-x 3.5. I created a simple game with edge bodies and one circular body to test box2d. Physics wasn't working well, so i thought i should convert pixels to meters and use that meters ...
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Body lost a velocity component when hitting a wall

I am creating a Breakout game using Box2D (of LibGdx if anyone interest). Everything works well until when the ball hits the wall when moving with a very small angle. Please look at the image for ...