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cocos2d-x sprite not bouncing correctly

  • chicken
    Likes 0
    Problem Description

    Hi

    I’m trying to get my sprite to jump on touch from a non-dynamic surface. It goes up fine, but on collision from a ‘grass’ sprite, it travels through. The collision is detected, as you can see from the CCLOG in the xcode window on the bottom left of the screencast. A video is here:

    https://youtu.be/mIrsFOmkgqw

    My code for the grass sprite is here:

    //grass

        auto grassSprite = Sprite::create("grass.png");

        PhysicsMaterial material(1.0f,1.0f,0.0f);

        //auto grassBody = PhysicsBody::createBox(grassSprite->getContentSize(), material);

        auto grassBody = PhysicsBody::createBox(grassSprite->getContentSize());

        grassBody->setDynamic(false);

        grassBody->setCollisionBitmask(1);

        grassBody->setContactTestBitmask(1);

        grassSprite->setPhysicsBody(grassBody);

     

    and my code for the sprite is here:

     PhysicsMaterial mat(0.0f,1.0f,0.0f);

        auto playerBody = cocos2d::PhysicsBody::createCircle(_player->getContentSize().width/2, mat);

        playerBody->setCollisionBitmask(2);

        playerBody->setContactTestBitmask(1);

        playerBody->setDynamic(true);

        _player->setPhysicsBody(playerBody);

        _layer->addChild(_player,100);

     

    Any idea what’s going on?

     

    Many thanks in advance

    Birju

     

  • Sonar Systems admin
    Likes 0

    For something as basic as this use your own bounding box collision detection.

  • chicken
    Likes 0

    Thanks, I’ve been messing around with this for a while now and you’re right so I am considering moving stuff around manually instead of relying on physics. Pretty much all sprites are ‘spongey’ when there is a collision. Any idea why this is? How can we prevent it? I’m using 3.10

    Thanks for your help

    Birju

  • Sonar Systems admin
    Likes 0

    How fast are your objects moving?

  • chicken
    Likes 0

    Hi thanks for the response.

    They’re not moving that fast really:

    auto jumpAction = cocos2d::JumpBy::create(1, Vec2::ZERO, visibleSize.height/4, 1);

    What is interesting is that when I drop the ball from the middle of the screen, it bounces fine (only a tiny overlap) but when I Jump it’s pretty bad, it does crazy stuff, I’ve uploaded a new video here:

    https://youtu.be/aP52PA2Vsa8

    Any help would be appreciated.

    Many thanks

    Birju

     

     

  • Sonar Systems admin
    Likes 0

    Have you tested it on a device?

  • chicken
    Likes 0

    yeah, figured it out – the jump action keeps a residual velocity. I instead did a MoveBy up and let it drop naturally using gravity. much better now.

    Thanks for the help

    Birju

  • Sonar Systems admin
    Likes 0

    Great to hear you have solved the problem.

     

    If you have anymore questions don’t hesitate to ask.

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