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  1. #1
    Registered User phil_mw60's Avatar
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    Hi,

    What is the best way to kill a sprite?

    In my game I have created a sprite array which stores a variable number of 'food' sprites which the games main character has to collect.

    When a collision is detected between the player sprite and one of the food sprites I increase the score. But I'm just wondering what the best method is for 'killing' the sprite?

    is it something like:

    foodsprite[i] = null?

    atm, I just set the x,y co-ords to 0,0 and set visible to false. Although this gives the impression the hero has eaten the food, the food sprite still exists.

    Thanks in advance for any help,

    Phil

  2. #2
    Super Contributor grahamhughes's Avatar
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    Yes, by setting the variable to null, you over-write the reference to the object. Once there are no references to an object, it becomes garbage, and the garbage collector will ensure that the memory it occupies is released.

    Make sure you add code to check pointers for null, to avoid NullPointerExceptions.

    Graham.

  3. #3
    Registered User phil_mw60's Avatar
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    Thanks Graham.

    How would I add code to check pointers for null?

    Is it something like:

    Code:
    if (foodsprite[i] == null)
    {
    // Do something here?
    }
    I don't think I have any code to do this at present.

    Thanks,

    Phil

  4. #4
    Super Contributor grahamhughes's Avatar
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    Well, more like:

    Code:
    if (foodsprite[i] != null) {
        // use foodsprite[i] here
    }
    Otherwise, if you try to use it, you'll get a NullPointerException.

    Graham.

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