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[Mattivc]

Ok, so i have a 2D array of data. Well, actually is a 1D array for technical reasons. But it its being used as a 2D by doing myArray[xPos+yPos*width].

What i am trying to is creating a method for allowing me to rotate the array 90, 180 or 270 degrees.

So for example:
[01][02][03]
[04][05][06]
[07][08][09]
[10][11][12]

Would become:
[10][07][04][01]
[11][08][05][02]
[12][09][06][03]

Doing this is trivial for a square array, problem is i need it to work for non-square array as well. I have been trying to figure it for myself and searching for a solution for a while now without luck. Any of you geniuses who got a solution or can point me in the right direction?

Also, as this is really a 1D array being used it shouldn't be absolutely necessary to create a new array, and copy the data to it. As it would be using a real 2D, because the width and height changes. And instead just move around the data in the existing array. Al tough that is just a bonus to settle my optimization OCD and not absolutely necessary for me to solve my problem.

[Polly]

Add a rotation parameter to your array interface so you can simply use a different address calculation for each of 4 angles.

Code:

switch(rotation)
{
  case   0: return myArray[x+y*w];
  case  90: return myArray[(h-x-1)*w+y];
  case 180: return myArray[w-x-1+(h-y-1)*w];
  case 270: return myArray[x*w+w-y-1];
}

[Mattivc]

This works fine for square arrays, but i need to have it work for non-square arrays as well.

[powly]

His version does - it just uses w and h differently for different angles.

[Polly]

His version does - it just uses w and h differently for different angles.

Exactly