objectgridportrayal2d.java

MASON代表多主体邻里或网络仿真(Multi-Agent Simulator of Neighborhoods or Networks)。它是乔治梅森大学用Java开发的离散事件多主体仿真核心库

package sim.portrayal.grid;
import sim.portrayal.*;
import sim.portrayal.simple.*;
import sim.field.grid.*;
import java.awt.*;
import java.awt.geom.*;
import sim.util.*;

/**
   A portrayal for grids containing objects, such as maybe agents or agent bodies.
*/

public class ObjectGridPortrayal2D extends FieldPortrayal2D
    {
    // a grey oval.  You should provide your own protrayals...
    SimplePortrayal2D defaultPortrayal = new OvalPortrayal2D();
    
    public ObjectGridPortrayal2D()
        {
        super();
        }
        
    public void setField(Object field)
        {
        dirtyField = true;
        if (field instanceof ObjectGrid2D ) this.field = field;
        else throw new RuntimeException("Invalid field for ObjectGridPortrayal2D: " + field);
        }
        
    public Portrayal getDefaultPortrayal()
        {
        return defaultPortrayal;
        }

    protected void hitOrDraw(Graphics2D graphics, DrawInfo2D info, Bag putInHere)
        {
        final ObjectGrid2D field = (ObjectGrid2D)(this.field);

        if (field==null) return;
        
        // Scale graphics to desired shape -- according to p. 90 of Java2D book,
        // this will change the line widths etc. as well.  Maybe that's not what we
        // want.
        
        // first question: determine the range in which we need to draw.
        // We assume that we will fill exactly the info.draw rectangle.
        // We can do the item below because we're an expensive operation ourselves
        
        final int maxX = field.getWidth(); 
        final int maxY = field.getHeight();
        if (maxX == 0 || maxY == 0) return; 
        
        final double xScale = info.draw.width / maxX;
        final double yScale = info.draw.height / maxY;
        int startx = (int)((info.clip.x - info.draw.x) / xScale);
        int starty = (int)((info.clip.y - info.draw.y) / yScale); // assume that the X coordinate is proportional -- and yes, it's _width_
        int endx = /*startx +*/ (int)((info.clip.x - info.draw.x + info.clip.width) / xScale) + /*2*/ 1;  // with rounding, width be as much as 1 off
        int endy = /*starty +*/ (int)((info.clip.y - info.draw.y + info.clip.height) / yScale) + /*2*/ 1;  // with rounding, height be as much as 1 off

        final Rectangle clip = (graphics==null ? null : graphics.getClipBounds());

        DrawInfo2D newinfo = new DrawInfo2D(new Rectangle2D.Double(0,0, xScale, yScale),
                                            info.clip);  // we don't do further clipping 

        if (endx > maxX) endx = maxX;
        if (endy > maxY) endy = maxY;
        if( startx < 0 ) startx = 0;
        if( starty < 0 ) starty = 0;
        for(int x=startx;x<endx;x++)
            for(int y=starty;y<endy;y++)
                {
                Object obj = field.field[x][y];
                Portrayal p = getPortrayalForObject(obj);
                if (!(p instanceof SimplePortrayal2D))
                    throw new RuntimeException("Unexpected Portrayal " + p + " for object " + 
                                               obj + " -- expected a SimplePortrayal2D");
                SimplePortrayal2D portrayal = (SimplePortrayal2D)p;
                
                // translate --- the   + newinfo.width/2.0  etc. moves us to the center of the object
                newinfo.draw.x = (int)(info.draw.x + (xScale) * x);
                newinfo.draw.y = (int)(info.draw.y + (yScale) * y);
                newinfo.draw.width = (int)(info.draw.x + (xScale) * (x+1)) - newinfo.draw.x;
                newinfo.draw.height = (int)(info.draw.y + (yScale) * (y+1)) - newinfo.draw.y;
                
                // adjust drawX and drawY to center
                newinfo.draw.x += newinfo.draw.width / 2.0;
                newinfo.draw.y += newinfo.draw.height / 2.0;
                
                if (graphics == null)
                    {
                    if (obj != null && portrayal.hitObject(obj, newinfo))
                        putInHere.add(getWrapper(new Int2D(x,y)));
                    }
                else
                    {
                    // MacOS X 10.3 Panther has a bug which resets the clip, YUCK
                    //                    graphics.setClip(clip);
                    portrayal.draw(obj, graphics, newinfo);
                    }
                }
        }

    public LocationWrapper getWrapper(Int2D location)
        {
        final ObjectGrid2D field = (ObjectGrid2D)(this.field);
        return new LocationWrapper(null, location, this)
            {
            Int2D loc = (Int2D) this.location;
            public Object getObject()
                { 
                return field.field[loc.x][loc.y];
                }
            
            public String getLocationName()
                {
                return ((Int2D)this.location).toCoordinates();
                }
            };
        }
    }