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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LibGDX Box2D Body shape transformation

In the following method my player Body is created: public static Body createPlayer (World world) { BodyDef bodyDef = new BodyDef(); bodyDef.type = BodyDef.BodyType.DynamicBody; ...
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Decrease force in a zero gravity world

I have a world with zero gravity. On a mouse pressed I apply a force so things drive away from the mouse. The problem is now that they keep on flying. How can i make them stop? ...
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How to apply Buoyant force to a Box2d body?

I have been following a formula to calculate the buoyant force needed to apply to a dynamic body to be able to simulate water. Fb = ρgV Fb - is the buoyant force ρ - density of the liquid g - ...
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LibGDX works well on android 4 and very bad on android 5 and 6

I have a problem with my game. The game is made with libgdx, scene2d and box2d and it uses an AssetManager. I tested this app on all my devices and here it is the results: Galaxy S3, android 4 ...
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LibGDX game crash without errors (maybe AssetManager)

i have a problem with my game. It's a endless run shooter/platform made with LibGDX (Scene2d and box2D). I do tests with LG G2, LG G3, Galaxy s4, desktop and android emulator and i have no one ...
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Box2D + SDL - Weird body positions

I'm having a problem where either my sprite, or my body position is off. Here's a picture so you can see exactly what's going on : (The box has stopped on the picture, probably because it's colliding ...
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42 views

How to create a linear plateform between two points?

I have a set of 2D coordinates. Their positions are regular on the X axis, but unpredictable on the Y axis: I would like to create slim platform between each point in order tu use it as ground for ...
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Box2dMapObjectParser isometric map - bodies have wrong position and size

I'm using Box2dMapObjectParser to load Tiled objects layer onto my IsometricTiledMapRenderer'ed TiledMap. It works OK with a UnitScale of 1 but the position is wrong and some shapes have weird ...
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How to split a screen in half using LibGDX without scaling?

I am currently working on a racing game with libGDX and I need to split the screen in half for a two-players mode. (Player 1 in first half and Player 2 in second half). I already have Camera1 that ...
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Best way to create defence(withdraw) algorthim libgdx?

I have created user body and enemy body. Enemy body uses the steering behavior created by gdx AI. User body have it own control inputprocessor. World doesnt have gravity. Enemy body arrives the user ...
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Libgdx Sprite rotation around specific point

I made complex dynamic body that rotates around other body that is static. It works perfectly, however I got messed up with sprite position on that body. Here's what I have now and here's what I ...
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Why is my tiled map moving when I move the camera in libGDX?

I use LibGDX. I have created a map with Tiled Map Editor and loaded it to the game. Everything else is working well, but when I move the camera, the map moves: it jumps or floats. My code: public ...
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Box2dWeb: rotating object about a point

I am having problem rotating box2d object back and forth around a point. To better understand my problem i have prepared an example clicking on key rotate the paddle when u click again the paddle ...
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Java Libgdx Attaching Sprite to Box2D Body

So I am working on programming a java 2D platformer for fun on the side and I have a rendered TMX level and a box2d body (just a circle shape) that I am currently using as my player. All the controls ...
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How can I simulate a basketball throw in LibGdx box2d?

So I want to simulate a similar throw like in the game Bouncy Basketball. Do i need to create a body and attach another body on it that would be the arm and then how would I apply force/impulse to the ...
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Box2d capsule stumbles on ground

I am working on a game with box2d and sdl. I Created a character and some boxes as ground, but faced the problem where the character would run a few meters, and stumble on one of the boxes' edge. I ...
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Box2D Physics Crazy

I have a simple Box2D Game with a dynamic player, a static floor, and a matrix of gems. The problem is that the physics engine goes crazy. You can see in this video: https://youtu.be/iaH_ex8eVVk ...
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Sprite not drawn on the same position as its Body LibGDX after implementing Pixels Per Meter Division on Box2D

I had a problem where the sprite was not positioned on Body correctly which I solved and you can see it here: Box2D is not positioned on the sprite correctly LibGDX After I solved that, I needed to ...
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How to handle two players playing on one keyboard with Box2D (LibGDX)?

I'm making a racing game with LibGDX and Box2D. I've been using this tutorial to implement the basic physics, and it works properly. My main problem is to implement two different sets of keys ...
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Box2D is not positioned on the sprite correctly LibGDX

I have a strange issue where my Box2D is not being positioned on the player correctly. Down is the picture: What I find more strange is that the Box2D is positioned correctly on the cloud that is ...
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Why is my character passing through in Box2D?

I have a collision problem in Box2D. I am trying to do a simple platform game with Libgdx, Box2D and TiledMap. I have a map made with TiledMap: I load the map in my Android game. I read all the ...
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LibGDX--constant high score in top corner

I'm currently programming a game using LibGDX and box2D. I have a sprite (player) that moves up the screen, kind of like doodle jump. I'd like to have my camera to be centered around the player at ...
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54 views

Box2D fixed timestep updating is twitchy on constant FPS

I'm messing around with libgdx and box2d and I'm trying to implement sidescroller movement with fixed timestep logic according to the famous Fix Your Timestep! tutorial/guide. However, logic updating ...
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Box2DLights in libGDX - Bad quality of the light gradient on Android

I am facing a problem while porting one of my libGDX project from desktop to Android : My game uses Box2DLights. While the light effect look very fancy on the desktop version of the game, it looks ...
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How to Implement a 2d camera object for a side scroller game

Ok so Heres the problem. I'm Using c++ with sfml for graphics and box2d for physics. I've tried an ultra simple cam movement in the past where i lock the player to the center of the screen and offset ...
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Libgdx + Box2d working with 2 cameras

Recently I have read that you can work with 2 cameras whenever you involve Box2d, which only works in meters. In my Renderer class, I receive all the entities in the game and then draw them. I work ...
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Box2D top down car weird spasm

im currently programming a 2d top down racing game with box2d and libgdx. i have a car body to which there are 4 wheels attached. these 4 wheels are attached with RevoluteJoints ( for the front ...
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Problem merging vertices of two polygonial bodies

SUMMARY I need help to create a weld joint that fixes the two bodies together in a way as illustrated in the first image. ISSUE I am having an issue where I cannot find out how to weld vertices of ...
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Box2d set sprite to body that rotates around specific point

I want to rotate kinematic body around a specific point (I already done this part using shape.setAsBox(1.8f / PPM, 0.2f / PPM, new Vector2(5.2f, 0), 0); What I try is this: PolygonShape shape ...
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Box2d - Texture lagging and flickering

I'm having issues with texture rendering in my game. I've done a lot of research and repeated the same steps of tutorials over the internet to render and update Sprite positions properly. Somehow, ...
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Libgdx and Box2D TiledMap render is not smooth

I'm building simple side scroller game. My player (square) move fast and it interacts with other world objects. Problem is when my player is moving it seems that all world is rendering somehow strange ...
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Libgdx box2d bodies go through other bodies

I'm developing a game using libGDX and box2d. I am facing a problem that bodies go through each other... I'm moving the body using a TouchPad by setTransform. I think the problem is that I use ...
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LibGDX: Is there any way to check if space between 2 bodies is free?

I know how to calculate the distance between 2 bodies in my game using Math.hypot(x,y); but I need to know if between those bodies the space is free, I mean, without any body.
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LibGDX & Box2D Actor Collision

I'm working on a LibGDX project, and I was wondering about the best way to define actors in a collision. I know this is probably a common question, but specifically I'm interested in beefing up one ...
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ChainShape in Box2D

I recently began to learn libgdx and I am stuck at a problem with the CainShape of Box2D. My first goal is to simply create a box with a ChainShape. In order to achieve that, I added four Vector2 ...
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Libgdx moving a body sequence

How can I move a body (box2d) to different points in an order. Like first it moves to 100,200 then to 200, 450 and so on? I've tried actions(and actor) but I can't get the point where the body is ...
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LibGDX Box2D texture on dynamic generated body

I'm creating a game that is similar to hill climb racing. I've generated the ground and now I want to add texture to the ground. Here is a screenshot of a game Here is my code (I create ground using ...
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libgdx box2d car wheel circle collision with ground

I'm creating game similar to hill climb racing. I have created car (which is basically polygon with two circles) and ground generated by sinus. Now here is the problem: when my car try to climb in ...
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Libgdx Box2D random positions and intervals falling bodies

I need to make that objects fall from the top of the screen random intervals and positions. Here's my code where I create lot of objects and add them to ArrayList private void createBalls() { ...
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Problems managing collision filtering

I have my character fixture and body(is a tank), so when I press the screen it throws a rocket(which also has a body and a fixture) that the player can controlll touching the screen. My game also has ...
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How to make a ball hit many tiled circular objects in LibGDX

Hey guys I've been learning to make games with LibGDX. I did a tiled map in Tiled and the rest of code in java using Android Studio. I could make a ball bounce on the flour using Box2D, but I can't ...
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Box2d How to connect distance joint to the ground?

I have a rectangular fixed size world. I want to connect a body inside it to any place(near that body) in the world with a b2DistanceJoint. Do I need to create a large static body with the size of the ...
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Box2D LibGDX Body.getPosition() and Body.getWorldCenter() problems

I have a problem with my game in Java with Box2D and LibGDX I found out that when I use body.getPosition() it is only half of that of body.getWorldCenter(). The problem here is for me that I use ...
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Movement for Box2D Bodies

I'm having trouble wrapping my head around something that should be relatively simple. I'm making a breakout clone using LibGDX and Box2D. I'm also using the Ashley ECS. For movement with bodies, I ...
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Moving box2D body with texture?

I was following the solution from this http://stackoverflow.com/questions/20180063/box2d-body-with-texture. I ended up getting this working for static bodies. But when trying to get the PolygonSprite ...
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How to dynamically draw a filled polygon with a given array of vertices?

Say I have a simple array of vertices (or floats with every odd index being the X of a vertex and every even being the Y), how could I paint all the area between the vertices? As in, I have maybe ...
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Most optimal way to load 2D world

I am creating a 2D car racing game. (Yes, a Hill Climb Racing clone) What I am doing right now is load 10% of the map every time the user gets to 7%. For example: Imagine the map has 10km. (10000m) ...
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Dealing with collisions across adjacent static bodies

The Problem: I have the following setup: A, B and C are rectangular static bodies in box2d. p is a circular dynamic body in box2d. The movement of 'p' is solely controlled by the current gravity ...
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Static body bridging two other static bodies

I have two box2d bodies like below, What I need is to create another body that kind of bridges this two bodies. I am not looking for a box2d joint, but a body that will be like a bridge touching the ...
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How do I set angular velocity/torque so that it's pointing to velocity/direction?

Right now, when I spawn a shootable object, it goes like this: Because I just set it's angle to this: float aimAngle = (float) Math.atan2(velocity.y, velocity.x); bullet.setBodyAngle(aimAngle); ...