Could any body diagnose the problem I am facing? As you run the demo you can see the middle part left blank, I need to fill the entire area..
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Polygon;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class FillDemo
{
public static void main(String aths[])
{
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel pnl = new PolygonDemo();
pnl.setSize(100, 200);
f.getContentPane().add(pnl);
f.setSize(400,280);
f.setLocation(200,200);
f.setVisible(true);
}
}
class PolygonDemo extends JPanel
{
public PolygonDemo()
{
setBackground(Color.white);
}
protected void paintComponent(Graphics g)
{
super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g;
Polygon p=new Polygon();
p.addPoint(100,0);
p.addPoint(100,100);
p.addPoint(0,100);
p.addPoint(0,0);
p.addPoint(80,0);
p.addPoint(80,20);
p.addPoint(40,20);
p.addPoint(40,40);
p.addPoint(80,40);
p.addPoint(80,100);
p.addPoint(20,100);
p.addPoint(20,80);
p.addPoint(60,80);
p.addPoint(60,60);
p.addPoint(20,60);
p.addPoint(20,0);
p.addPoint(0,0);
g2.setColor(Color.BLACK);
g2.draw(p);
g2.setColor(new Color(120,250,100));
g2.fillPolygon(p);
//g2.fillPolygon(p.xpoints,p.ypoints,p.npoints);
}
}
Many thanks in advance
Your polygon intersects with itself. The fillPolygon method can not clearly decide which point is in and which is out. From the fillPolygon javadoc:
The area inside the polygon is defined using an even-odd fill rule, also known as the alternating rule.
Perhaps you can split your polygon into three single ones.
Draw Rectangle and Fill Color.....
public void paint(Graphics g)
{
int[] xPoints = {100,50,150};
int[] yPoints = {100,200,200};
g.setColor(Color.black);
g.drawPolygon(xPoints, yPoints, 3);
g.setColor(Color.red);
g.fillPolygon(xPoints, yPoints, 3);
}
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