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Thread: gravity in 2d game

  1. #1
    Join Date
    Oct 2012
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    Default gravity in 2d game

    when user hit up key, jump get set to true and when user let go of up key jump get set to false.
    gravity = 2
    velocity = 20
    y = y postion of my player


    1st - if i hold up key my player go up 20 pics, but when i keep on going down for ever.
    2nd - if i hit up key and let go, then hit up key and let go, and so on ..... it keep on going up for ever.

        if(jump == true){
          velocity -= gravity;
           y -= velocity;	
        else if(jump == false){
          velocity = 20;

    problem #2 is bc i am seting velocity = 20 in else if. to fix this problem i can just del the statment.
    problem #1 is really hard and i cant find a good sloution for it. may be if i have a test inside of
     if(jump == true){

  2. #2
    Crazy Cat Lady KevinWorkman's Avatar
    Join Date
    Oct 2010
    Washington, DC
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    Thanked 636 Times in 540 Posts

    Default Re: gravity in 2d game

    And what happened when you tried that?

    By the way, putting your game logic inside an infinite loop like that probably isn't a good idea. It's better to use a Timer.
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