thisBuildingX = building.mapX;
thisBuildingY = building.mapY;

import greenfoot.*;  // (World, Actor, GreenfootImage, Greenfoot and MouseInfo)
import java.awt.Color;
import java.util.List;
import java.util.ArrayList;

/**
 * Write a description of class AirWorld here.
 * 
 * @author (your name) 
 * @version (a version number or a date)
 */
public class AirWorld extends World
{
    Map map = new Map();
    GreenfootImage mapImg = map.getImage();
    final int MAPIMGWIDTH = mapImg.getWidth();
    final int MAPIMGHEIGHT = mapImg.getHeight();
    Building buildTemplate = new Building(0,0);
    GreenfootImage buildImg = buildTemplate.getImage();
    final int BUILDINGWIDTH = buildImg.getWidth();
    final int BUILDINGHEIGHT = buildImg.getHeight();
    final int MAPWIDTH = MAPIMGWIDTH * BUILDINGWIDTH;
    final int MAPHEIGHT = MAPIMGHEIGHT * BUILDINGHEIGHT;
    private List<Building> building = new ArrayList<Building>();
    int leftBound = 0;
    int bottomBound = MAPHEIGHT;
    int topBound = MAPHEIGHT - getHeight();
    int rightBound = getWidth();

    public AirWorld()
    {    
        // Create a new world with 600x400 cells with a cell size of 1x1 pixels.
        super(600, 600, 1); 
        drawMap();
        update();
    }

    public void drawMap()
    {
        for(int y = 0; y < MAPIMGHEIGHT; y++)
        {
            for(int x = 0; x < MAPIMGWIDTH; x++)
            {
                int colorRGB = mapImg.getColorAt(x,y).getRGB();
                if(colorRGB == Color.BLACK.getRGB())
                {
                    int mapX = x * BUILDINGWIDTH + BUILDINGWIDTH/2;
                    int mapY = y * BUILDINGHEIGHT + BUILDINGHEIGHT/2;
                    building.add(new Building(mapX, mapY));
                }
            }
        }
    }

    public void update()
    {
        Building thisBuilding;
        int thisBuildingX;
        int thisBuildingY;
        int screenX;
        int screenY;
        for(int i=0; i < building.size(); i++)
        {
            thisBuilding = building.get(i);
            thisBuildingX = building.mapX;
            thisBuildingY = building.mapY;

            if(thisBuildingX >= leftBound && thisBuildingX<=rightBound && thisBuildingY>=topBound && thisBuildingY<=bottomBound)
            {
                screenX = thisBuildingX - leftBound;
                screenY = thisBuildingY - topBound;
                if(thisBuilding.getWorld() == null)
                {
                    addObject(thisBuilding, screenX, screenY);
                }
            }
        }
    }
}