Java Graphics - Draw Triangle and Check Given Point is Inside or Outside

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I have given here Java Graphics program to draw a triangle and check whether the given point is inside or outside the triangle

Source Code

import java.lang.*;
import java.util.*;
import java.util.List;
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;

   public class PointInTriangle extends Frame {

     public Polygon mypolygon = new Polygon();
     public Point mypoint = new Point();

     public static void drawPixel(Graphics g, int x, int y, int size, Paint color) 
     {
         Graphics2D ga = (Graphics2D)g;
         Shape circle = new Ellipse2D.Float(x, y, size, size);    
         ga.setPaint(color);
         ga.draw(circle);
         ga.setPaint(color);
         ga.fill(circle);
     }

     public void paint(Graphics g) {
        Graphics2D ga = (Graphics2D)g;
        ga.setPaint(Color.red);
        ga.draw(mypolygon);
        ga.setPaint(Color.green);
        drawPixel(g, mypoint.x, mypoint.y, 3, Color.blue);
     }
     
     public static int IsPointInBoundingBox(float x1, float y1, float x2, float y2, float px, float py)
      {
          float left, top, right, bottom; // Bounding Box For Line Segment
       
          // For Bounding Box
          if(x1 < x2)
          {
              left = x1;
              right = x2;
          }
          else
          {
              left = x2;
              right = x1;
          }
       
          if(y1 < y2)
          {
              top = y1;
              bottom = y2;
          }
          else
          {
              top = y2;
              bottom = y1;
          }
       
          if( (px+0.01) >= left && (px-0.01) <= right && 
                  (py+0.01) >= top && (py-0.01) <= bottom )
          {
              return 1;
          }
          else
              return 0;
       
      }  
     
     public static int LineSegmentIntersection(float l1x1, float l1y1, float l1x2, float l1y2,
                               float l2x1, float l2y1, float l2x2, float l2y2)
      {
       
          float dx, dy;
          float intersection_X = 0;
          float intersection_Y = 0;
       
          dx = l1x2 - l1x1;
          dy = l1y2 - l1y1;
       
          float m1 = dy / dx;
       
          float c1 = l1y1 - m1 * l1x1; // which is same as y2 - slope * x2
       
          dx = l2x2 - l2x1;
          dy = l2y2 - l2y1;
       
          float m2 = dy / dx;
          float c2 = l2y1 - m2 * l2x1; // which is same as y2 - slope * x2
       
          if( (m1 - m2) == 0)
              return 0;
          else
          {
              intersection_X = (c2 - c1) / (m1 - m2);
              intersection_Y = m1 * intersection_X + c1;
          }
       
          if(IsPointInBoundingBox(l1x1, l1y1, l1x2, l1y2, intersection_X, intersection_Y) == 1 && IsPointInBoundingBox(l2x1, l2y1, l2x2, l2y2, intersection_X, intersection_Y) == 1)
          {
              return 1;
          }
          else
              return 0;
      }
     
      public static int ReadInteger()
      {
           try
           {
                 InputStreamReader input = new InputStreamReader(System.in);
                 BufferedReader reader = new BufferedReader(input);
                 return Integer.parseInt(reader.readLine());
           }
           catch (Exception e)
           {

                 e.printStackTrace();
                 return 0;
           }
      }
      
      
         
  public static void main(String args[]) 
  {
      List< Integer > srcpoints = new ArrayList< Integer >();
     
      for(int i = 0; i < 3; i++)
      {
         System.out.format("Enter x[%d]: ", i + 1);
         srcpoints.add(ReadInteger());
         System.out.format("Enter y[%d]: ", i + 1);
         srcpoints.add(ReadInteger());
      }
      /***
      srcpoints.add(200);srcpoints.add(200);
      srcpoints.add(75);srcpoints.add(75);
      srcpoints.add(100);srcpoints.add(200);
      srcpoints.add(srcpoints.get(0));
      srcpoints.add(srcpoints.get(1));
      ***/

      PointInTriangle frame = new PointInTriangle();
      for(int i = 0; i < srcpoints.size(); i++)
      {
         int x = srcpoints.get(i++);
         int y = srcpoints.get(i);
         frame.mypolygon.addPoint(x, y);
      }
     
      System.out.format("Enter Point X: ");
      int x = ReadInteger();
      System.out.format("Enter Point Y: ");
      int y = ReadInteger();
     
     /*** 
      int x = 85;
      int y = 100;
     ***/
      int px = x + 1000;
      int py = y;
      frame.mypoint.x = x;
      frame.mypoint.y = y;
      
    
      int nCountIntersections = 0;
    
      nCountIntersections += LineSegmentIntersection(srcpoints.get(0), srcpoints.get(1), srcpoints.get(2), srcpoints.get(3), x, y, px, py);
      nCountIntersections += LineSegmentIntersection(srcpoints.get(2), srcpoints.get(3), srcpoints.get(4), srcpoints.get(5), x, y, px, py);
      nCountIntersections += LineSegmentIntersection(srcpoints.get(4), srcpoints.get(5), srcpoints.get(0), srcpoints.get(1), x, y, px, py);

      if( (nCountIntersections % 2) == 1)
           System.out.println("The Given Point is inside the triangle");
       else
           System.out.println("The Given Point is outside the triangle");
      
          
      frame.addWindowListener(
      new WindowAdapter()
      {
         public void windowClosing(WindowEvent we)
         {
            System.exit(0);
         }
      }
      );
           
      frame.setSize(300, 250);
      frame.setVisible(true);
   }
}

/***
Enter x[1]: 200
Enter y[1]: 200
Enter x[2]: 75
Enter y[2]: 75
Enter x[3]: 100
Enter y[3]: 200
Enter Point X: 85
Enter Point Y: 100
The Given Point is inside the triangle
***/

Output