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I am using box2d on the iphone to create a game. I have a body that is effected by gravity to move down and not right or left. It will get hit by another body and will then be moving right or left. I then have a reset button which moves the body back to its starting point. The only problem is that it is still moving right or left. How can I counteract the forces that a ball is already traveling? How can I get rid of this right and left movement when I reset my game?

user891123
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1 Answers1

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Box2d automatically clears the forces each simulation step. I think you are just changing your body's position when resetting, but not its velocity. Add this code to your reset method:

body->SetLinearVelocity(b2Vec2(0,0));
body->SetAngularVelocity(0);
Max
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Andrew
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  • I've tried this way but doesn't work when two object close to each other http://stackoverflow.com/questions/39716111/cocos2dx-unable-to-set-velocity-0-0 – TomSawyer Sep 27 '16 at 08:04
  • @TomSawyer: they probably collide after you reset the velocities and that causes their velocity to change again – Andrew Sep 27 '16 at 18:36
  • I think resetting the velocity make one object stand still. it's impossible to collide to the other. Anyway to make sure one object has been stopped? – TomSawyer Sep 27 '16 at 20:39