Hi, I'm just starting out with obj-c and I've got an idea for a project that requires a fairly odd storage structure and I'd like advice on how to implement it. The real question Is this an object I should be creating with malloc/free and pointers or is it doable with object oriented storage facilities like NSArray and Hashtables? Also, ideas about how to actually do it are welcome.I guess this would be the model for the program. Here's what it needs to do:Store many 2D segment objects (X1,Y1,X2,Y2)Each segment has one associated integer property. (think brightness?)No two segments can have the same 4 coordinates.have a method to quickly look up all the segments that have the same X1,Y1.have a method to quickly look up all the segments that have the same X1.have a method to quickly look up all the segments that have the same X2,Y2.have a method to return all segments.In practice there can be hundreds or possibly a thousand segments.The size of the space/canvas or whatever needs to be resizable. (Meaning a 1D array representing a n-D array might be inefficient)Maximally the dimensions of the canvas will be 128x512. This would be a very extreme case.I've done this in the past and I've used a 2D array representing the X1,Y1 space and then filled cell in that 2D array with a hashtable full of X2,Y2,Value objects. This has been passable but leaves much to be desired. Also, There's no 2D array in obj-c.Thanks for your time,-Matt

Custom storage strategies in Obj -C for beginner.

Hi, I'm just starting out with obj-c and I've got an idea for a project that requires a fairly odd storage structure and I'd like advice on how to implement it. The real question Is this an object I should be creating with malloc/free and pointers or is it doable with object oriented storage facilities like NSArray and Hashtables? Also, ideas about how to actually do it are welcome.

I guess this would be the model for the program. Here's what it needs to do:

Store many 2D segment objects (X1,Y1,X2,Y2)
Each segment has one associated integer property. (think brightness?)
No two segments can have the same 4 coordinates.
have a method to quickly look up all the segments that have the same X1,Y1.
have a method to quickly look up all the segments that have the same X1.
have a method to quickly look up all the segments that have the same X2,Y2.
have a method to return all segments.
In practice there can be hundreds or possibly a thousand segments.
The size of the space/canvas or whatever needs to be resizable. (Meaning a 1D array representing a n-D array might be inefficient)
Maximally the dimensions of the canvas will be 128x512. This would be a very extreme case.

I've done this in the past and I've used a 2D array representing the X1,Y1 space and then filled cell in that 2D array with a hashtable full of X2,Y2,Value objects. This has been passable but leaves much to be desired. Also, There's no 2D array in obj-c.

Thanks for your time,

-Matt

Posted on Mar 9, 2013 4:53 PM