public void adjustTimes(int previousStep, int newStep){
    int difference = newStep - previousStep;
    for(int y = 0; y < this.lastSeenTimeStep.length; y++)
      for(int x = 0; x < this.lastSeenTimeStep[y].length; x++)
        if(this.lastSeenTimeStep[y][x] >= 0)
          this.lastSeenTimeStep[y][x] += difference;
  }