Java Tutorial/2D Graphics/Curve

CubicCurve2D.Float

   <source lang="java">

import java.awt.Frame; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.geom.CubicCurve2D; public class MainClass extends Frame {

 public static void main(String[] args) {
   (new MainClass()).setVisible(true);
 }
 public MainClass() {
   super("Shape Sampler");
   setSize(400, 550);
 }
 public void paint(Graphics g) {
   Graphics2D g2d = (Graphics2D) g;
   CubicCurve2D cubcurve = new CubicCurve2D.Float(30, 400, 150, 400, 200, 500, 350, 450);
   g2d.draw(cubcurve);
 }

}</source>

QuadCurve2D.Float

   <source lang="java">

import java.awt.Frame; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.geom.QuadCurve2D; public class ShapeSampler extends Frame {

 public static void main(String[] args) {
   (new ShapeSampler()).setVisible(true);
 }
 public ShapeSampler() {
   super("Shape Sampler");
   setSize(400, 550);
 }
 public void paint(Graphics g) {
   Graphics2D g2d = (Graphics2D) g;
   QuadCurve2D quadcurve = new QuadCurve2D.Float(50, 300, 320, 300, 350, 400);
   g2d.draw(quadcurve);
 }

}</source>

Select a Curve To Display Its Points and Flatness Index

   <source lang="java">

import java.awt.Canvas; import java.awt.Color; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.Rectangle; import java.awt.geom.QuadCurve2D; import java.awt.geom.Rectangle2D; import java.util.Vector; import javax.swing.JFrame; public class QuadCurveControlPoint extends JFrame {

 DrawingCanvas canvas = new DrawingCanvas();
 public QuadCurveControlPoint() {
   getContentPane().add(canvas);
   setSize(500, 500);
   setVisible(true);
 }
 public static void main(String arg[]) {
   new QuadCurveControlPoint();
 }
 class DrawingCanvas extends Canvas {
   Vector quadCurves = new Vector();
   QuadCurve2D selectedCurve = null;
   Rectangle2D boundingRec = null;
   public DrawingCanvas() {
     setSize(400, 200);
     quadCurves.addElement(new QuadCurve2D.Float(20, 20, 80, 160, 120, 20));
     quadCurves.addElement(new QuadCurve2D.Float(120, 100, 160, 40, 200, 180));
     for (int i = 0; i < quadCurves.size(); i++) {
       QuadCurve2D curve = (QuadCurve2D) quadCurves.elementAt(i);
       selectedCurve = curve;
       boundingRec = curve.getBounds2D();
       System.out.println(selectedCurve.getX1());
       System.out.println(selectedCurve.getY1());
       System.out.println(selectedCurve.getCtrlX());
       System.out.println(selectedCurve.getCtrlY());
       System.out.println(selectedCurve.getX2());
       System.out.println(selectedCurve.getY2());
       double flatness = selectedCurve.getFlatness();
       System.out.println(flatness);
     }
   }
   public void paint(Graphics g) {
     Graphics2D g2D = (Graphics2D) g;
     for (int i = 0; i < quadCurves.size(); i++) {
       g2D.draw((QuadCurve2D) quadCurves.elementAt(i));
     }
     if (boundingRec != null) {
       drawHighlightSquares(g2D, boundingRec);
     }
   }
   public void drawHighlightSquares(Graphics2D g2D, Rectangle2D r) {
     double x = r.getX();
     double y = r.getY();
     double w = r.getWidth();
     double h = r.getHeight();
     g2D.setColor(Color.black);
     g2D.fill(new Rectangle.Double(x - 3.0, y - 3.0, 6.0, 6.0));
     g2D.fill(new Rectangle.Double(x + w * 0.5 - 3.0, y - 3.0, 6.0, 6.0));
   }
 }

}</source>