/* Dressed Obstacle */

import java.awt.*;
import java.util.Vector;

public class D_Obstacle
{
public int npoints;
public int shield;
public Polygon body;
public Polygon boundpoly;
public Vector[] scenary;
    
public D_Obstacle()
    {}

public void dress   
(Polygon obstacle, int rover_width,  int rover_height)
    {
	int i, upline, downline;
	double upx, upy, upr, downx, downy, downr, angle, extension;
	this.npoints = obstacle.npoints;
	this.shield = Math.min(rover_width,rover_height)/2+1;
	int myxpoints[] = new int [obstacle.npoints];
	int myypoints[] = new int [obstacle.npoints];
	for (i=0; i<this.npoints; i++)
	{
	    upline = i+1;
	    if (upline == this.npoints) upline = 0;
	    upx = obstacle.xpoints[i] - obstacle.xpoints[upline];
	    upy = obstacle.ypoints[i] - obstacle.ypoints[upline];
	    upr = Math.sqrt(upx*upx+upy*upy);
	    upx /= upr;
	    upy /= upr;
	    downline = i-1;
	    if (downline < 0) downline = this.npoints-1;
 	    downx = obstacle.xpoints[i] - obstacle.xpoints[downline];
	    downy = obstacle.ypoints[i] - obstacle.ypoints[downline];
	    downr = Math.sqrt(downx*downx+downy*downy);
	    downx /= downr;
	    downy /= downr;
	    angle = Math.acos (upx*downx+upy*downy);
	    extension = this.shield / Math.sin(angle);
	    myxpoints[i] = obstacle.xpoints[i] +
		(int) Math.round(extension * (upx + downx));
	    myypoints[i] = obstacle.ypoints[i] +
		(int) Math.round(extension * (upy + downy));
	}
	this.body = new Polygon (obstacle.xpoints, obstacle.ypoints, obstacle.npoints);
	this.boundpoly = new Polygon (myxpoints,myypoints,this.npoints);
    }
    
    /*
public void scene_list(D_Obstacle obstacles[], int num_obstacle,
		       D_Gem gem[],int num_gem)
    {
	int i, j, k,l;
	Point p1= new Point(), p2 = new Point();
	boolean blocked;
	scenary = new Vector[boundpoly.npoints];
	for (i=0; i< npoints; i++)
	{
	    p1.x =  boundpoly.xpoints[i];
	    p1.y =  boundpoly.ypoints[i];	    
	    for(j=0; j< num_gem; j++)
	    {
		p2.x = gem[j].x;
		p2.y = gem[j].y;
		blocked = false;
		for (k=0; k< num_obstacle; k++)
		{
		    if(Path.intersect(p1, p2, obstacles[k].body))
		    { blocked = true; break;}
		}
		if(!blocked) scenary[i].addElement(p2);
	    }
	    
	    for(j=0; j< num_obstacle; j++)
	    {
		for(l=0; l< obstacles[j].npoints; l++)
		{
		    p2.x = obstacles[j].boundpoly.xpoints[l];
		    p2.y = obstacles[j].boundpoly.ypoints[l];
		    if( (p2.x==p1.x) && (p2.y==p1.y)) break;
		    blocked = false;
		    for (k=0; k< num_obstacle; k++)
		    {
			if(Path.intersect(p1, p2, obstacles[k].body))
			{ blocked = true; break;}
		    }
		    if(!blocked) scenary[i].addElement(p2);
		}
	    }
	}
    }
    */
    
public void show(Graphics g)
    {
	g.setColor(Color.black);
	g.fillPolygon(this.boundpoly);
	g.setColor(Color.red);
	g.fillPolygon(this.body);
    }

} // class D_Obstacle ends