/*Composite03.java 12/12/99
 Copyright 1999, R.G.Baldwin
  
 Illustrates use of the constructors of the Color class
 to achieve transparency with solid-fill colors.
  
 Similar to Composite01 except that Composite01
 uses the  AlphaComposite class to achieve
 transparency.
  
 Draws a 4-inch by 4-inch Frame on the screen.
  
 Translates the orgin to the center of the Frame.
  
 Draws a pair of X and Y-axes centered on the new
 origin.
  
 Draws a big circle centered on the origin underneath
 all of the ellipses.
  
 Uses rotation and translation to fill three ellipses in
 each of the four quadrants.  The ellipses intersect at 
 their center.  Each is rotated by 60 degrees relative
 to the one below it.  The order is:
   Red ellipse on the bottom
   Green ellipse in the middle
   Blue ellipse on the top
   
 Each ellipse has a non-transparent outline, 
 approximately 0.05 inches in width.
   
 TRANSPARENCY
 Upper-left quadrant
 No transparency
  
 Upper-right quadrant
 All three ellipses are 30-percent transparent
  
 Lower-left quadrant
 All three ellipses are 60-percent transparent
  
 Lower-right quadrant
 All three ellipses are 90-percent transparent
   
 Whether the dimensions in inches come out right
 or not depends on whether the method 
 getScreenResolution() returns the correct resolution
 for your screen.
  
 Tested using JDK 1.2.2 under WinNT Workstation 4.0
 ******************************************/
 import java.awt.geom.*;
 import java.awt.*;
 import java.awt.event.*;
 import java.awt.image.*;
  
 class Composite03{
   publicstaticvoid main(String[] args){
     GUI guiObj = new GUI();
   }//end main
 }//end controlling class Composite03
  
 class GUI extends Frame{
   int res;//store screen resolution here
   staticfinalint ds = 72;//default scale, 72 units/inch
   staticfinalint hSize = 4;//horizonal size = 4 inches
   staticfinalint vSize = 4;//vertical size = 4 inches
   
   GUI(){//constructor
     //Get screen resolution
     res = Toolkit.getDefaultToolkit().
                                      getScreenResolution();
     //Set Frame size
     this.setSize(hSize*res,vSize*res);
     this.setVisible(true);
     this.setTitle("Copyright 1999, R.G.Baldwin");
         
     //Window listener to terminate program.
     this.addWindowListener(new WindowAdapter(){
       public void windowClosing(WindowEvent e){
         System.exit(0);}});
   }//end constructor
   //-----------------------------------------------------//
   
   //Override the paint() method
   public void paint(Graphics g){
     //Downcast the Graphics object to a
     // Graphics2D object
     Graphics2D g2 = (Graphics2D)g;
     
     //Scale device space to produce inches on the
     // screen based on actual screen resolution.
     g2.scale((double)res/72,(double)res/72);
  
     //Translate origin to center of Frame
     g2.translate((hSize/2)*ds,(vSize/2)*ds);
  
     //Draw x-axis
     g2.draw(new Line2D.Double(
                                        -1.5*ds,0.0,1.5*ds,0.0));
     //Draw y-axis
     g2.draw(new Line2D.Double(
                                        0.0,-1.5*ds,0.0,1.5*ds));
     
     //Draw a big circle underneath all of the ellipses.
     g2.setStroke(new BasicStroke(0.1f*ds));
     Ellipse2D.Double bigCircle = new Ellipse2D.Double(
                             -1.5*ds,-1.5*ds,3.0*ds,3.0*ds);
     g2.draw(bigCircle);
  
     Ellipse2D.Double theEllipse;
     g2.setStroke(new BasicStroke(0.05f*ds));
  
     //Translate origin to upper-left quadrant
     g2.translate(-1.0*ds,-1.0*ds);
     
     //Red horizontal ellipse
     theEllipse = new Ellipse2D.Double(
                            -1.0*ds,-0.25*ds,2.0*ds,0.5*ds);
                            
     g2.setPaint(Color.red);//nontransparent outline
     g2.draw(theEllipse);
                            
     g2.setPaint(new Color(
                1.0f,0.0f,0.0f,1.0f));//red, not transparent
     g2.fill(theEllipse);
     
     //Green ellipse at 60 degrees
     theEllipse = new Ellipse2D.Double(
                            -1.0*ds,-0.25*ds,2.0*ds,0.5*ds);
     g2.rotate(Math.PI/3.0);//rotate 60 degrees
     
     g2.setPaint(Color.green);//nontransparent outline
     g2.draw(theEllipse);
     
     g2.setPaint(Color.green);//nontransparent outline
     g2.draw(theEllipse);
     
     g2.setPaint(new Color(
              0.0f,1.0f,0.0f,1.0f));//green, not transparent
     g2.fill(theEllipse);
     
     //Blue ellipse at 120 degrees
     theEllipse = new Ellipse2D.Double(
                            -1.0*ds,-0.25*ds,2.0*ds,0.5*ds);
     g2.rotate((Math.PI/3.0));//rotate 60 more degrees
     
     g2.setPaint(Color.blue);//nontransparent outline
     g2.draw(theEllipse);
     
     g2.setPaint(new Color(
               0.0f,0.0f,1.0f,1.0f));//blue, not transparent
     g2.fill(theEllipse);
  
     
     //Translate origin to upper-right quadrant
     g2.rotate(-2*(Math.PI/3.0));//undo prev rotation
     g2.translate(2.0*ds,0.0*ds);
     
     //Red horizontal ellipse
     theEllipse = new Ellipse2D.Double(
                            -1.0*ds,-0.25*ds,2.0*ds,0.5*ds);
                            
     g2.setPaint(Color.red);//nontransparent outline
     g2.draw(theEllipse);
                            
     g2.setPaint(new Color(
                1.0f,0.0f,0.0f,0.7f));//red, 30% transparent
     g2.fill(theEllipse);
     
     //Green ellipse at 60 degrees
     theEllipse = new Ellipse2D.Double(
                            -1.0*ds,-0.25*ds,2.0*ds,0.5*ds);
     g2.rotate(Math.PI/3.0);//rotate 60 degrees
  
     g2.setPaint(Color.green);//nontransparent outline
     g2.draw(theEllipse);    
  
     g2.setPaint(new Color(
              0.0f,1.0f,0.0f,0.7f));//green,30% transparent
     g2.fill(theEllipse);
     
     //Blue ellipse at 120 degrees
     theEllipse = new Ellipse2D.Double(
                            -1.0*ds,-0.25*ds,2.0*ds,0.5*ds);
     g2.rotate((Math.PI/3.0));//rotate 60 more degrees
     
     g2.setPaint(Color.blue);//nontransparent outline
     g2.draw(theEllipse);
     
     g2.setPaint(new Color(
               0.0f,0.0f,1.0f,0.7f));//blue, 30% transparent
     g2.fill(theEllipse);
  
  
     //Translate origin to lower-left quadrant
     g2.rotate(-2*(Math.PI/3.0));//undo prev rotation
     g2.translate(-2.0*ds,2.0*ds);
     
     //Red horizontal ellipse
     theEllipse = new Ellipse2D.Double(
                            -1.0*ds,-0.25*ds,2.0*ds,0.5*ds);
                            
     g2.setPaint(Color.red);//nontransparent outline
     g2.draw(theEllipse);
                            
     g2.setPaint(new Color(
                1.0f,0.0f,0.0f,0.4f));//red, 60% transparent
     g2.fill(theEllipse);
     
     //Green ellipse at 60 degrees
     theEllipse = new Ellipse2D.Double(
                            -1.0*ds,-0.25*ds,2.0*ds,0.5*ds);
     g2.rotate(Math.PI/3.0);//rotate 60 degrees
     
     g2.setPaint(Color.green);//nontransparent outline
     g2.draw(theEllipse);
     
     g2.setPaint(new Color(
              0.0f,1.0f,0.0f,0.4f));//green,60% transparent
     g2.fill(theEllipse);
     
     //Blue ellipse at 120 degrees
     theEllipse = new Ellipse2D.Double(
                            -1.0*ds,-0.25*ds,2.0*ds,0.5*ds);
     g2.rotate((Math.PI/3.0));//rotate 60 more degrees
     
     g2.setPaint(Color.blue);//nontransparent outline
     g2.draw(theEllipse);
     
     g2.setPaint(new Color(
               0.0f,0.0f,1.0f,0.4f));//blue, 60% transparent
     g2.fill(theEllipse);
  
  
     //Translate origin to lower-right quadrant
     g2.rotate(-2*(Math.PI/3.0));//undo prev rotation
     g2.translate(2.0*ds,0.0*ds);
     
     //Red horizontal ellipse
     theEllipse = new Ellipse2D.Double(
                            -1.0*ds,-0.25*ds,2.0*ds,0.5*ds);
                            
     g2.setPaint(Color.red);//nontransparent outline
     g2.draw(theEllipse);
                            
     g2.setPaint(new Color(
                1.0f,0.0f,0.0f,0.1f));//red, 90% transparent
     g2.fill(theEllipse);
     
     //Green ellipse at 60 degrees
     theEllipse = new Ellipse2D.Double(
                            -1.0*ds,-0.25*ds,2.0*ds,0.5*ds);
     g2.rotate(Math.PI/3.0);//rotate 60 degrees
     
     g2.setPaint(Color.green);//nontransparent outline
     g2.draw(theEllipse);
     
     g2.setPaint(new Color(
              0.0f,1.0f,0.0f,0.1f));//green,90% transparent
     g2.fill(theEllipse);
     
     //Blue ellipse at 120 degrees
     theEllipse = new Ellipse2D.Double(
                            -1.0*ds,-0.25*ds,2.0*ds,0.5*ds);
     g2.rotate((Math.PI/3.0));//rotate 60 more degrees
     
     g2.setPaint(Color.blue);//nontransparent outline
     g2.draw(theEllipse);
     
     g2.setPaint(new Color(
               0.0f,0.0f,1.0f,0.1f));//blue, 90% transparent
     g2.fill(theEllipse);
  
   }//end overridden paint()
     
 }//end class GUI
 //================================//

Figure 7