Dynamic Object Creation (and Management)...

This is a discussion on Dynamic Object Creation (and Management)... within the C++ Programming forums, part of the General Programming Boards category; For each 'item' on the screen, I want to store its data in variables within a class. All 'items' have ...

  1. #1
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    Dynamic Object Creation (and Management)...

    For each 'item' on the screen, I want to store its data in variables within a class. All 'items' have the same variables, so I want to create an object (of the 'item's class) for each 'item' on the screen, and adjust the variables of each individual 'item' (i.e. variable "x_position", of object "ship1", of class "frieghter"... Though the class probably won't be that specific unless it's through inheritence).

    The problem is, I want to be able to delete and create these objects on run-time. I could create these as 'static' object arrays in the memory prior to their actual use in the game, but aside from limiting the number of 'items' I can have thoughout the game (unless I declared more arrays, which would require memory even after the destruction of the 'item'... Another memory draw-back), it would require more memory for 'items' not even present in the context of the game.

    So I was wondering how I could create object arrays (or just objects), that I could delete individually, while maintaining numerical order (like lists, vectors, and maps).

    In other words, referring to my previous 'example', create class "ships", with child-class "frieghter", and then create "ship1, ship2, ship3... ship'n'", and then be able to delete those individually (and free the memory used by them). Or, more simply, is there any way I can use a variable to name an object of class?
    If a=b, and b=c, then a=c, except where void and prohibited by law...

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    I would create a vector of ship classes... each vector specific to the type of ship.

    or try a vector of vectors.. where the first dimension corrosponds to the type of ship.. second dimension is the specific ship itself.
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    Yes, you can create objects of user defined defined classes dynamically.

    >is there any way I can use a variable to name an object of class?

    No you can't use variables to name objects, but you can use variables as members of objects to do essentially the same thing. For example, if each object had a member variable of type int you could use it to keep track of how many objects you had at any given time or how many objects had been created since the beginning of the program or in what order they were added to the group of currently active objrcts, etc.
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    Elad, do you mean instead of using static arrays as member variables, use vectors (or lists or whatever) as the member variables, and then have a plain int member variable to denote how many instances of the 'item' are being considered? Like, instead of having multiple instances of a class, and deleting or adding those to represent the number of 'items' and their properties, use one instance of each specific class (like The Brain was talking about), and then have the properties of each 'item' (x position, y position, health, et cetera) vectors within the classes, whose size is determined by a main variable indicating the number of said 'items' on screen (or in-game)?... 'Cause I think I see what you guys mean. Thanks for the replies, by the way.
    If a=b, and b=c, then a=c, except where void and prohibited by law...

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