Koch Snowflake

Code for Koch Snowflake

// appropriate includes here
#include <GL.h>
#include <Gl/glut.h>
#include <stdlib.h>
#include <math.h>


class GLintPoint{
public:
	GLint x, y;
};

// function prototypes
void myInit(void);
void myDisplay(void);
void lineThing(double x1, double x2, double y1, double y2, int level);
void makeLine(double x1, double x2, double y1, double y2);
void drawDot(void);
int x, y ;


//<<<<<<<<<<<<<<< myinit >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
void myInit(void)
{
	glClearColor(1.0, 1.0, 1.0, 0.0) ; // set white background color
	glColor3f(1.0f, 0.0f, 0.5f) ; // set the drawing color
	glPointSize(2.0) ; // a dot is 2 by 2 pixels
	glMatrixMode (GL_PROJECTION) ;
	glLoadIdentity () ;
	gluOrtho2D(0.0, 640.0, 0.0, 640.0) ;
}

//<<<<<<<<<<<<<<< lineThing >>>>>>>>>>>>>>>>>>>>>>>>>>>>
void lineThing(double x1, double x2, double y1, double y2, int level)
{
	double angle;
	double length;
	const double PI = 3.1411592653;


	if(level <= 0)
	{
		x1 = (x1 - 0)*640/2;
		y1 = (1 - y1)*640/2;
		x2 = (x2 - 0)*640/2;
		y2 = (1 - y2)*640/2;
		makeLine(x1, y1, x2, y2);
	}
	else
	{
		angle = atan2((y2 - y1), (x2-x1));
		length = sqrt( pow((y2-y1),2) + pow ((x2-x1), 2))/3.0;
		
		x2 = (x1 + length*cos(angle));
		y2 = (y1 + length*sin(angle));
		lineThing(x1, x2, y1, y2, level - 1);
		x1 = x2;
		y1 = y2;
		
		angle = angle - PI/3;
		x2 = (x1 + length*cos(angle));
		y2 = (y1 + length*sin(angle));
		lineThing(x1, x2, y1, y2, level - 1);
		x1 = x2;
		y1 = y2;

		angle = angle + 2*PI/3;
		x2 = (x1 + length*cos(angle));
		y2 = (y1 + length*sin(angle));
		lineThing(x1, x2, y1, y2, level - 1);
		x1 = x2;
		y1 = y2;

		angle = angle - PI/3;
		x2 = (x1 + length*cos(angle));
		y2 = (y1 + length*sin(angle));
		lineThing(x1, x2, y1, y2, level - 1);
		
	}
	glFlush();

}




//<<<<<<<<<<<<<<< makeLine >>>>>>>>>>>>>>>>>>>>>>>>>>>>
void makeLine(double x1, double y1, double x2, double y2)
{
		glBegin(GL_LINES); //use constant GL_LINES here
			glVertex2i(x1, y1);
			glVertex2i(x2, y2);
		glEnd();

}


//<<<<<<<<<<<<<<< drawDot >>>>>>>>>>>>>>>>>>>>>>>>>>>>
void drawDot()
{
	glClear(GL_COLOR_BUFFER_BIT);
	lineThing(0.2, 1.8, -0.5, -0.5, 6);
	lineThing(1.8, 1.0, -0.5, 0.885, 6);		
	lineThing(1.0, 0.2, .885, -0.5, 6);	

}





//<<<<<<<<<<<<<< main >>>>>>>>>>>>>>>>>>>>>>>>>>>>
void main(int argc, char** argv)
{

	glutInit(&argc, argv) ; //initializes the toolkit
	glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB) ; //set the display mode
	glutInitWindowSize(640, 640) ; //  setwindow size
	glutCreateWindow("Iminhell"); // open the screen window 
	glutDisplayFunc(drawDot) ; // register the redraw functions

	
	myInit(); //additional initializations as necessary
	glutMainLoop() ; // go into a perpetual loop

}