draw polar graph in java
Does anyone know how I can get started to draw a polar graph in java and plot some points on this graph? I mean the circles and lines, I wish to do this with something like swing, and not use any library like Jfreechart Thanks
You might like to look at Lissajous curves; an example of a = 5, b = 4 (5:4)
is shown below.
Addendum: Once you see how to plot points in xy coordinates, then you should look at converting between polar and Cartesian coordinates.
public class LissajousPanel extends JPanel {
private static final int SIZE = 400;
private GeneralPath path = new GeneralPath();
@Override
public Dimension getPreferredSize() {
return new Dimension(SIZE, SIZE);
}
@Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
g2d.setRenderingHint(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
double dt = Math.PI / 180;
int w = getWidth() / 2;
int h = getHeight() / 2;
path.reset();
path.moveTo(w, h);
for (double t = 0; t < 2 * Math.PI; t += dt) {
double x = w * Math.sin(5 * t) + w;
double y = h * Math.sin(4 * t) + h;
path.lineTo(x, y);
}
g2d.setColor(Color.blue);
g2d.draw(path);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(new LissajousPanel());
f.pack();
f.setVisible(true);
}
});
}
}
Java2D is part of the official JDK and fits your purposes perfectly. You can find the java doc here: Java2d