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

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How do I change the relative origins of a Box2D World and a TiledMap in Libgdx?

I'm playing around with Box2D and TiledMaps and I've come across this minor annoyance. As you can see, both Box2D and TiledMap render at the center of the screen. This forces me to compensate by ...
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89 views

Box2d - Attaching a fired arrow to a moving enemy

I am firing an arrow from the player to moving enemies. When the arrow hits the enemy, I want it to attach exactly where it hit and cause the enemy (a square) to tumble to the ground. Excluding the ...
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1answer
183 views

LibGdx sprite rotation vs Box2D physics rotation problem

LibGdx sprite rotation vs Box2D physics rotation problem Tearing my hair out on this one. I am an experienced software developer, but very new to LibGdx and Box2D development. I am writing a game ...
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1answer
74 views

Change the shape of body dynamically

I have a problem where i have a ballon which i need to continuously inflate and defalte in update method, I have tried to used setScaleCenter but it is not giving desired result. Below is a code i am ...
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1answer
137 views

Dynamic Hills like Contre Jour in Cocos2d

I'm interested in maps/environments which are flexible and change at runtime, such as those in Contre Jour. I have looked for a long time to find out how to make this effect, but I couldn't find an ...
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1answer
609 views

Libgdx import bin/xml/json from physics editor

I'm using Libgdx. I did a simple json file in Physics Body Editor and I don't have any idea how could I import it into my physic world in libgdx. Any idea will be appreciated. P.S: Sorry if there ...
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1answer
21 views

Box2D `ApplyLinearImpulse` is not working whereas `SetLinearVelocity` works

I need to mimic jumping behavior for the player in my game. Player consists of two fixtures with circle and rectangle shapes. Rectangle I use to detect ground and it is a sensor. Is some point for ...
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1answer
49 views

Set Position of multiple bodies

I have a character composed of five bodies which are tied together by a lot of joints. On of them is the overall chassis, to which all forces and impulses are applied to move the whole Character. All ...
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354 views

Communication between Box2D and libGDX Stage (Scene2D) running in separate threads

I'm making a physics based 2D game using libGDX and Box2D. I want to move the execution of the simulation out of render thread. I use immutable messages and the BlockingQueue to pass the information ...
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328 views

Box2D Static-Dynamic body joint eliminates collisions

I have a static body A, and a dynamic body B, and a dynamic body C. A is filtered to not collide with anything, B and C collide with each other. I wish to create a joint between B and A. When I ...
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166 views

Rotating an object about a point (2D) using box2d

i just started developing using box2d on flixel and i realise the pivot point of the rotation of an object in box2d is set to the center of an object. i had read on forums and i found out that ...
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47 views

What's the difference between Box2D and tweening?

It seems like Box2D can be used to move sprites across the screen, so how does this differ from tweening? Is it that Box2D is for physical collision detections and tweening is just animations?
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105 views

Collision function calls before colliding

My Box2D contact listener class is calling post solve and beginning the contact function before colliding? This is causing my object to bounce back before hitting the ground. What could be causing ...
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1answer
1k views

Create Box2D and engine polygon Box2D body without sprite

Hey I have created my body using following code: (please read full description) Body polyBody; final BodyDef mBodyDef = new BodyDef(); mBodyDef.type = BodyDef.BodyType.DynamicBody; ...
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1answer
302 views

How do I change gravity of box2d world after world is created?

I want to modify the world of box2d after creating it, namely to change the gravity vector. Is there a way to do this?