/*
 *  File:  TriangleTest2.java
 *
 *  Drawing triangles (an exercise)
 *
 *  Copyright:  Northeast Parallel Architectures Center
 *  
 */

import java.applet.Applet;
import java.awt.Graphics;
import java.awt.Polygon;
import java.awt.Color;

public class TriangleTest2 extends Applet {

   // create references to three triangles:
   private Triangle triangle1, triangle2, triangle3;
   
   public void init() {
   
      // instantiate an isosceles triangle:
      triangle1 = new Triangle( 50, 25, 75, 100, 25, 100 );
      // instantiate a right triangle:
      triangle2 = new Triangle( 125, 25, 175, 100, 125, 100 );
      // instantiate an equilateral triangle:
      triangle3 = new Triangle( 71, 125, 129, 125, 100, 175 );

   }
   
   public void paint( Graphics g ) {

      // draw the first triangle:
      triangle1.draw( g );

      // fill the second triangle:
      triangle2.fill( g );

      // fill the third triangle:
      g.setColor( Color.red );
      triangle3.fill( g );

   }
   
}

// A triangle is a polygon with three sides:
class Triangle extends Polygon {

   // Triangle constructor #1:
   public Triangle() {
      // invoke the constructor of the superclass Polygon:
      super();
   }

   // Triangle constructor #2:
   public Triangle( int x1, int y1, 
                    int x2, int y2, 
                    int x3, int y3  ) {
 
      // invoke the constructor of the superclass Polygon:
      super();
 
      // the 'this' reference is optional:
      this.addPoint( x1, y1 );
      this.addPoint( x2, y2 );
      this.addPoint( x3, y3 );
 
   }

   // Instance methods:
   public void draw( Graphics g ) {
      g.drawPolygon( this );
   }
   public void fill( Graphics g ) {
      g.fillPolygon( this );
   }

}