Question

Is there a way to do a cross section of a 3D Array?

What I mean is: Cut the array along the Z axis so you get a 2D plane of the X axis and Y axis.

I need to do this so I can store them as separate sections in an ArrayList, or even potentially a List.

Thanks.

Answer 1

I’m not sure C# has an out-of-the-box way of doing this, so you’d have to implement something yourself:

T[,] SliceThroughZ<T>(T[,,] threeDee, int zIndex)
{
    var xLength = threeDee.GetLength(0);
    var yLength = threeDee.GetLength(1);
    var twoDee = new T[xLength, yLength];
    for (int i = 0; i < xLength; i++)
        for (int j = 0; j < yLength; j++)
            twoDee[i, j] = threeDee[i, j, zIndex];

    return twoDee;
}

Alternatively, rather than making a copy, you could implement a wrapper class with a two-dimensional indexer that simply queries the original array. You’d lose array-specific methods, though.

class ZSliceWrapper<T>
{
    public T[, ,] Source { get; set; }
    public int ZIndex { get; set; }

    public T this[int xIndex, int yIndex]
    {
        get // you could even implement a set.
        {
            return Source[xIndex, yIndex, ZIndex];
        }
    }
}