How can I rotate an array of array ?

Question

There is my problem:
I have an array of array and i want to rotate it n time by 90°:
For exemple, go from:

[
[1, 1, 1],
[1, 0, 1],
[0, 0, 1],
[1, 1, 1],
]

To:

[
[1, 0, 1, 1],
[1, 0, 0, 1],
[1, 1, 1, 1],
]

As a goddot beginner this problem is really too abstract for me, even in python i don't manage to succeed.
Also sorry for bad english i am a beginner too.

Answer 1

# Rotates array 90 degrees clockwise, assuming that array is a full rectangle (all rows same size)
func rotate_array(arr) -> Array:
    var new_arr = []
    for i in range(len(arr[0])):
        var row = []
        for j in range(len(arr)):
            row.append(arr[len(arr) - j - 1][i])
        new_arr.append(row)
    return new_arr

Comments

To build on your super helpful answer:

func rotate_array(arr,count):
    for _c in range(count):
        var new_arr = []
        for i in range(len(arr[0])):
            var row = []
            for j in range(len(arr)):
                row.append(arr[len(arr) - j - 1][i])
            new_arr.append(row)
        arr=new_arr
    return arr

I've added a simple rotate 90° this many times counter.

This gives the benefit of easily rotating or horizontal / vertical flipping [mirroring] any array [like a tilemap for a level].

One could also simulate counter-clockwise rotation for a Tetris-like game.

Currently, I'm using this function for game level generation that is similar to Spelunky.

Answer 2

I don't know if this is the most efficient way to do it, but this should work.
It's pretty simple. Create a new 2d array, with the opposite dimensions (flip width and height). Then just fill it up with the reversed indices.

Edit: exuin's answer is better

func rotate_array(arr):
    var height = arr.size()
    var width = arr.front().size()
    var new_arr = []

    # Make a 2d array
    for i in range(width):
        var row = []
        row.resize(height)
        new_arr.append(row)

    # Swap the rows and columns
    for i in range(height):
        for j in range(width):
            new_arr[j][i] = arr[height - i - 1][j]

    return new_arr

Comments

Nevermind, I just realized this is not what you wanted.
For what you want, I think it might be better to use a dictionary rather than a 2d array. I'll try to work out an actual solution