Name: rm29839 Date: 06/11/98


When constructing clip rectangles for graphics
operations it is desireable to be able to
intersect two rectangles and pass the result to
setClip.

If the two rectangles are disjoint
(no intersection) then intersect returns a rect
with a negitive width or height. If you pass
such a rectangle to setClip, getClipBounds will
return the same rectangle with the absolute value
of all points in the rectangle that was passed to
setClip.

That can really mess up GUI code.
import java.awt.*;
import java.awt.image.*;
import java.awt.geom.*;


public class MMM extends Frame{
  public static void main (String [] args){
    new MMM();
  }
  public MMM(){
    setSize(200,200);
    show();
    validate();
  }
  
    public void paint(Graphics g){
      Rectangle r1 = new Rectangle(0,0,100,100);
      Rectangle r2 = new Rectangle(200,200,20,20);
      Rectangle r3 = r1.intersection(r2);
      System.out.println("intersect :(" + (int)r3.getX() + "," + (int)r3.getY() + "," + (int)r3.getWidth() + "," + (int)r3.getHeight() + ")" );g.setClip(r3);
      Rectangle r4 = g.getClipBounds();
      System.out.println("getClipBounds:(" + (int)r4.getX() + "," + (int)r4.getY() + "," + (int)r4.getWidth() + "," + (int)r4.getHeight() + ")" );
      
    }
  
}
(Review ID: 33441)
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