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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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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What is the Box2D coordinates system?

I know that for Box2d I need to translate pixels to meters which is easy peasy. However my problem is what is the orientation of Box2D coordinates system? Is this the same as screen one (right += x, ...
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Unable to find good parameters for behavior of a puck in Farseer

EDIT: I have tried all kinds of variations now. The last one was to adjust the linear velocity in each step: newVel = oldVel * 0.9f - all of this including your proposals kind of work, however in the ...
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Making an object swing from one rope to another

I am trying to make a Tarzan like game with Cocos2D and Box2D. I am having issues with the physics - making an object swing from one rope to another. I am not really sure how to do this. Could anyone ...
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How can I cancel a contact in a b2ContactListener?

To know when contacts happen we can derive from b2ContactListener and implement our own solution which is great. I'm wondering is there anyway we can cancel a contact, that is to say when we hit begin ...
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Box2D Platform body not moving player body along with it

I am creating a game using Box2D (Javascript implementation) - and I added the ability to have a static platform, that is moved along an axis as a function of a sine. My problem is when the player ...
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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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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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Floating point precision issue with Box2D

I'm using Box2D and I am putting edge tiles as b2Bodies so that the tile world can have physics: The problem is that there are 3 b2_kinematic bodies under the player right beside each other. Every ...
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Getting a sprite from multiple sprites for right material pattern

Not sure how accurate the question was but I'll put it this way. I'm developing a game where player will construct his/her own stuff, like bridge, building etc. using cocos2d-iphone and Box2D. First ...
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AS3: limit objects to stage width?

I want to limit the creation of objects acording to the stage width. My method is the following: for (var i:int = 0; i<7; i++){ If I put something like this, it won't work for (var i:int = ...