// Computer Graphics - Amir Hesami
// This program shows the effect of the mouse callback function.
// freehand1.cpp


#include <GL/glut.h>

#pragma comment(lib, "opengl32.lib")  // Link OpenGL32.lib
#pragma comment(lib, "glu32.lib")	  // Link Glu32.lib
#pragma comment(lib, "glut32.lib")    // Link Glut32.lib
#pragma comment(linker, "/entry:\"mainCRTStartup\"" )  // set the entry point to be main()
#pragma comment(linker, "/subsystem:\"Windows\"" )  // set the entry point to be main()


GLsizei wh=500,ww=500;// initial window size
   
void display(void);
void init(void);
void mouse(int,int,int,int);
void mydisplay(int x1,int y1);
void reshape(int w, int h);
void key(unsigned char, int, int);


int main(int argc, char** argv)
{
	glutInit(&argc, argv);
	glutInitDisplayMode( GLUT_SINGLE | GLUT_RGB);
	glutInitWindowSize(500, 500);
	glutInitWindowPosition(100,100);
	glutCreateWindow("FREEHAND 1");
	init();
	glutReshapeFunc(reshape);
	
	glutMouseFunc(mouse);
	glutDisplayFunc(display);
	glutMainLoop();
	return 0;
}

void display(void)
{}

void mydisplay(int xmin,int ymin)
{	
	
	glColor3f(1.0,0.0,0.0);
	glPointSize(3.0);
	glBegin(GL_POINTS);
	   glVertex2i(xmin,ymin);
	        
    glEnd();
	glFlush();
}

void init(void)
{
	

	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glOrtho(0.0, (GLdouble)ww,0.0 , (GLdouble)wh,-1.0,1.0);
	glClearColor(1.0, 1.0, 1.0, 1.0);
	glClear(GL_COLOR_BUFFER_BIT);
	glFlush();
}

void reshape(int ww, int wh)
{   
    glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glOrtho(0.0, (GLdouble)ww,0.0 , (GLdouble)wh,-1.0,1.0);
    glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	glViewport(0,0,ww, wh);
	glClearColor(1.0,1.0,1.0,1.0);
    glClear(GL_COLOR_BUFFER_BIT);
	glFlush();
}

void mouse(int button, int state, int x, int y)
{
	static int x1,y1,x2,y2;
	
	if(button==GLUT_LEFT_BUTTON && state==GLUT_DOWN)
	{
		x1=x;
     	y1=wh-y;
		
	}
     
     
	   mydisplay(x1,y1);
	
	
	

}