private boolean collision (int [] [] block, int blockX, int blockY)
    {
        for (int i = 0; i < block.length; i++)
        {
            for (int j = 0; j < block[0].length; j++)
            {
                if (block[i][j] != 0)
                {
                    if (0 > i + blockX || i + blockX >= this.fieldWidth || 0 > j + blockY || j + blockY >= this.fieldHeight)
                    {
                        return true;
                    }
                    if (field [blockX + i] [blockY + j] != 0)
                    {
                        return true;
                    }
                }
            }
        }
        return false;
    }