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Thread: Collosion detection for QGraphicsPixmapItem objects. how?

  1. #1
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    Post Collosion detection for QGraphicsPixmapItem objects. how?

    hello eveyone

    I'm making a time trial platformer game in qt5.
    I'm trying to detect collosions between the instances of the Background class but it's not working.
    [through qDebug(), I found out that it's not even entering the for loop.]

    Background class is a subclass of the QGraphicsPixmapItem.
    all of the platforms that the player jumps on, are instances of the Background class.

    myscene is an instance of the Myscene class which is a subclass of the QGraphicsScene.
    m_player is an instance of the Player class which is a subclass of the QGraphicsPixmapItem.

    checkcollosion() is called every time scene gets updated.

    Qt Code:
    1. void Myscene::checkcollosion()
    2. {
    3. QList<QGraphicsItem*> items = collidingItems(m_player);
    4.  
    5. for (int i=0, number = items.count(); i<number; ++i)
    6. {
    7. if (Background *back = qgraphicsitem_cast<Background*>(items.at(i)))
    8. {
    9. }
    10. }
    11. }
    To copy to clipboard, switch view to plain text mode 

    I guess because Background is a subclass of QGraphicsPixmapItem, the collidingItems() doesn't work for it.
    and can qgraphicsitem_cast be used for casting QGraphicPixmapItem or is it only for QGraphicsItem ?

    so how can I fix this?

  2. #2
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    Default Re: Collosion detection for QGraphicsPixmapItem objects. how?

    Quote Originally Posted by curiouscoding View Post
    I guess because Background is a subclass of QGraphicsPixmapItem, the collidingItems() doesn't work for it.
    Not sure why you mean it wouldn't work for pixmap items, they do have a shape.

    Quote Originally Posted by curiouscoding View Post
    and can qgraphicsitem_cast be used for casting QGraphicPixmapItem or is it only for QGraphicsItem ?
    A QGraphicsPixmapItem is a QGraphicsItem. So yes.

    Cheers,
    _

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