132 lines
4.4 KiB
Java
132 lines
4.4 KiB
Java
import java.awt.*;
|
|
import java.awt.geom.*;
|
|
|
|
/**
|
|
* This class demonstrates the use of union, intersection, difference and symmetric difference for
|
|
* Shape objects.
|
|
* Die Operationen werden auf einen und ein Rechteck angewendet.
|
|
*
|
|
* @author Frank Klawonn
|
|
* Last change 07.01.2005
|
|
*/
|
|
public class AreaExample extends Frame
|
|
{
|
|
//Constructor
|
|
AreaExample()
|
|
{
|
|
//Enables the closing of the window
|
|
addWindowListener(new MyFinishWindow());
|
|
}
|
|
|
|
|
|
public void paint(Graphics g)
|
|
{
|
|
Graphics2D g2d = (Graphics2D) g;
|
|
//Use of antialiasing to have nicer lines
|
|
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
|
|
//Radius of the circle
|
|
int radius = 50;
|
|
//Position of the circle
|
|
int startx = 100;
|
|
int starty = 100;
|
|
//Size of the rectangle
|
|
int width = 70;
|
|
int height = 100;
|
|
//Positioning of the rectangle relative to the circle
|
|
int rectshiftx = -10;
|
|
int rectshifty = 10;
|
|
//Translation of the rectangle and the circle to the right,
|
|
//when one of the set-theoretic operations is carried out.
|
|
int xshift = 140;
|
|
//Union: add
|
|
//Generate a circle and a rectangle.
|
|
Ellipse2D.Double circle1 = circleDouble(startx,starty,radius);
|
|
Rectangle2D.Double rect1 = new Rectangle2D.Double(startx+rectshiftx,
|
|
starty+rectshifty,
|
|
width,
|
|
height);
|
|
//Change the circle and the rectangle into Area objects.
|
|
Area c1 = new Area(circle1);
|
|
Area r1 = new Area(rect1);
|
|
//Compute their union.
|
|
c1.add(r1);
|
|
//Draw the union.
|
|
//g2d.setPaint(Color.green);
|
|
g2d.fill(c1);
|
|
//Intersection
|
|
//Generate a circle and a rectangle (shifted to the right).
|
|
Ellipse2D.Double circle2 = circleDouble(startx+xshift,starty,radius);
|
|
Rectangle2D.Double rect2 = new Rectangle2D.Double(startx+rectshiftx+xshift,
|
|
starty+rectshifty,
|
|
width,
|
|
height);
|
|
//Change the circle and the rectangle into Area objects.
|
|
Area c2 = new Area(circle2);
|
|
Area r2 = new Area(rect2);
|
|
//Compute their intersection.
|
|
c2.intersect(r2);
|
|
//Draw the intersection.
|
|
//g2d.setPaint(Color.red);
|
|
g2d.fill(c2);
|
|
//Difference
|
|
//Generate a circle and a rectangle (shifted to the right).
|
|
Ellipse2D.Double circle3 = circleDouble(startx+2*xshift,starty,radius);
|
|
Rectangle2D.Double rect3 = new Rectangle2D.Double(startx+rectshiftx+2*xshift,
|
|
starty+rectshifty,
|
|
width,
|
|
height);
|
|
//Change the circle and the rectangle into Area objects.
|
|
Area c3 = new Area(circle3);
|
|
Area r3 = new Area(rect3);
|
|
//Compute their difference.
|
|
c3.subtract(r3);
|
|
//Draw the difference.
|
|
//g2d.setPaint(Color.blue);
|
|
g2d.fill(c3);
|
|
//Symmetric difference: XOR
|
|
//Generate a circle and a rectangle (shifted to the right).
|
|
Ellipse2D.Double circle4 = circleDouble(startx+3*xshift,starty,radius);
|
|
Rectangle2D.Double rect4 = new Rectangle2D.Double(startx+rectshiftx+3*xshift,
|
|
starty+rectshifty,
|
|
width,
|
|
height);
|
|
//Change the circle and the rectangle into Area objects.
|
|
Area c4 = new Area(circle4);
|
|
Area r4 = new Area(rect4);
|
|
//Compute their symmetric difference.
|
|
c4.exclusiveOr(r4);
|
|
//Draw their symmetric difference.
|
|
//g2d.setPaint(Color.yellow);
|
|
g2d.fill(c4);
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
* Erzeugt einen Kreis mit Radius radius und Mittelpunkt (x,y).
|
|
*
|
|
* @param x x-Koordinate des Kreismittelpunktes
|
|
* @param y y-Koordinate des Kreismittelpunktes
|
|
* @param radius Der Radius des Kreises
|
|
*
|
|
* @return Kreis mit Radius radius und Mittelpunkt (x,y)
|
|
*/
|
|
public Ellipse2D.Double circleDouble(double x, double y, double radius)
|
|
{
|
|
return(new Ellipse2D.Double(x-radius,y-radius,2*radius,2*radius));
|
|
}
|
|
|
|
|
|
|
|
|
|
public static void main(String[] argv)
|
|
{
|
|
AreaExample f = new AreaExample();
|
|
f.setTitle("Operations for combining areas");
|
|
f.setSize(600,250);
|
|
f.setVisible(true);
|
|
}
|
|
|
|
}
|
|
|