Heightmap

function Mapfill_Heightmap_Fractal(Randomness, Seed)
    local Chunk_Size = 16

    -- Fill it with random start values
    local Size = 2 -- SIZE OF THE RANDOM ARRAY
    local Heightmap = CREATE SOME RANDOM ARRAY HERE, ATLEAST 2x2 !!!!!!!!!!!!!!!!!!!!!!

    -- Do the iterations
    while Size < Chunk_Size do

        -- Resize the array
        for ix = Size+1, Size*2 do
            Heightmap[ix] = {}
            --for iy = Size+1, Size*2 do
            --  Heightmap[ix][iy] = 0
            --end
        end
        for ix = Size, 0, -1 do
            for iy = Size, 0, -1 do
                Heightmap[ix*2][iy*2] = Heightmap[ix][iy]
            end
        end
        Size = Size * 2

        -- The diamond step
        for ix = 1, Size, 2 do
            for iy = 1, Size, 2 do
                Heightmap[ix][iy] = (Heightmap[ix+1][iy+1] + Heightmap[ix-1][iy+1] + Heightmap[ix+1][iy-1] + Heightmap[ix-1][iy-1]) / 4
            end
        end

        -- The square step
        for ix = 0, Size, 2 do
            for iy = 1, Size, 2 do
                Heightmap[ix][iy] = (Heightmap[ix][iy-1] + Heightmap[ix][iy+1]) / 2
            end
        end
        for ix = 1, Size, 2 do
            for iy = 0, Size, 2 do
                Heightmap[ix][iy] = (Heightmap[ix-1][iy] + Heightmap[ix+1][iy]) / 2
            end
        end
    end

    -- Return the Heightmap

    return Heightmap
end