private Cell[][] buildCells(int cellSize) {
        cellsWidth = dungeonWidth / cellSize;
        cellsHeight = dungeonHeight / cellSize;
        Cell[][] cells = new Cell[cellsHeight][cellsWidth];

        for (int i = 0; i < dungeonHeight; i += cellSize) {
            for (int j = 0; j < dungeonWidth; j += cellSize) {

                cells[i / cellSize][j / cellSize] = new Cell(i, j, i + cellSize - 1,
                        j + cellSize - 1);

            }
        }

        return cells;
    }