Sierpinski Triangle

#include<stdio.h>
#include<GL/glut.h>
#include<math.h>
#include <stdlib.h>
struct Point {
  float x, y;
  Point(float x = 0, float y = 0): x(x), y(y) {}
  Point midpoint(Point p) {return Point((x + p.x) / 2.0, (y + p.y) / 2.0);}
};
void display() {
  glClear(GL_COLOR_BUFFER_BIT);
  static Point vertices[] = {Point(0.0, 0.0), Point(200.0, 500.0), Point(500.0, 0.0)};
  static Point p = vertices[0];
  glBegin(GL_POINTS);
  for (int k = 0; k < 100000; k++) {
    p = p.midpoint(vertices[rand() % 3]);
    glVertex2f(p.x, p.y);
  }
  glEnd();
  glFlush();
}
void init() {
  glClearColor(0.25, 0.0, 0.2, 1.0);
  glColor3f(0.6, 1.0, 0.0);
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  glOrtho(0.0, 500.0, 0.0, 500.0, 0.0, 1.0);
}
int main(int argc, char** argv) {
  glutInit(&argc, argv);
  glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
  glutInitWindowSize(500, 500);
  glutInitWindowPosition(40, 40);
  glutCreateWindow("Sierpinski Triangle");
  glutDisplayFunc(display);
  init();
  glutMainLoop();
}