//#include <GL/glut.h>
#include <iostream>
#include <cstdio>
#include <cmath>

using namespace std;

int MAX = 1000;

typedef struct {
	double x;
	double y;
	double z;
} Point;

Point p[100], perP[100];
Point prp;
int n;
double zvp;

void perProFormula(Point purana, Point prp, Point &perTransKarke, double whereViewScreenCutsZAxis);
void showPoint(Point p); //only for x and y coordinates
void draw_point();

/*void drawPoint(double x, double y) {
	glPointSize(2);

	glBegin(GL_POINTS);
	glColor3f(0.0f, 1.0f, 0.0f);
	glVertex2f(x / MAX,  y / MAX);
	glEnd();

	glFlush();
}

void drawLineDDA(double x1, double y1, double x2, double y2) {
	glPointSize(2);
	glBegin(GL_POINTS);
	glColor3f(0.0f, 1.0f, 0.0f);

	double dx = x2 - x1;
	double dy = y2 - y1;
	int i;

	double p;
	if (abs(dx) > abs(dy)) {
		p = abs(dx);
	} else {
		p = abs(dy);
	}

	double incx = dx / p;
	double incy = dy / p;

	double x = x1, y = y1;
	glVertex2f(x / MAX, y / MAX);

	for (i = 0; i < p; i++) {
		x += incx;
		y += incy;

		glVertex2f(x / MAX, y / MAX);
	}
	glEnd();

	glFlush();
}*/
/*
void display() {
	glClearColor(0.0f, 0.0f, 1.0f, 1.0f);
	glClear(GL_COLOR_BUFFER_BIT);

	glPointSize(5);

	int x[4] = {-100, -100, 100, 100};
	int y[4] = {700, 500, 500, 700};

	int i;
	for (i = 0; i < 4; i++) {
		drawLineDDA(x[i], y[i], x[(i + 1) % 4], y[(i + 1) % 4]);
	}

	drawLineDDA(-50,    0,   50, 500);
	drawLineDDA(-150,   0, -500, 400);
	drawLineDDA(-500, 400, -100, 700);
	drawLineDDA(-50,    0, -400, 400);
	drawLineDDA(-400, 400, -100, 600);

	drawLineDDA(50,    0, -50, 500);
	drawLineDDA(150,   0, 500, 400);
	drawLineDDA(500, 400, 100, 700);
	drawLineDDA(50,    0, 400, 400);
  	drawLineDDA(400, 400, 100, 600);

         
	for (int i = 0; i < 4; i++) {
		drawLineDDA(perP[i].x, perP[i].y, perP[(i + 1) % 4].x, perP[(i + 1) % 4].y);
		//cout << perP[i].x << " " << perP[i].y << " " << perP[(i + 1) % 4].x << " " << perP[(i + 1) % 4].y << endl;
	}

	for (int i = 4; i < 24; i += 2) {
        drawLineDDA(perP[i].x, perP[i].y+10, perP[i + 1].x, perP[i + 1].y);
        //cout << perP[i].x << " " << perP[i].y << " " << perP[(i + 1)].x << " " << perP[(i + 1)].y << endl;
	}

	glEnd();
	glFlush();

	//glutPostRedisplay();
}
*/
int main(int argc, char** argv) {
    double theta = atan(0.1);
    double xx = 10 - sin(theta) * 10;
    cout << xx << endl;

	prp.x = 0;
	prp.y = -100;
	prp.z = 10;

	zvp = -5;

	n = 24;
	int x[] = {-100, -100, 100, 100, -50,  50, -150, -500, -500, -100, -50, -400, -400, -100, 50, -50, 150, 500, 500, 100, 50, 400, 400, 100};
	int y[] = {700,   500, 500, 700,   0, 500,    0,  400,  400,  700,   0,  400,  400,  600,  0, 500,   0, 400, 400, 700,  0, 400, 400, 600};

	for (int i = 0; i < n; i++) {
                float a = atan(0.1);
		p[i].x = x[i]/10;
             
		p[i].y = y[i]/10;
		p[i].z = 0;

		perProFormula(p[i], prp, perP[i], zvp);
	}


//	glutInit(&argc, argv);
//	glutCreateWindow("GVC LAB TEST");
//	glutInitWindowSize(1000, 1000);
//	glutInitWindowPosition(0, 0);
//	glutDisplayFunc(display);
//	glutMainLoop();

	return 0;
}


void perProFormula(Point p, Point prp, Point &perP, double zvp) {
	double a = (prp.z - zvp) / (prp.z - p.z);
	double b = (zvp - p.z) / (prp.z - p.z);

	perP.x = p.x * a + prp.x * b;
	perP.y = p.y * a + prp.y * b;

	showPoint(perP);
}

void showPoint(Point p) { //only for x and y coordinates
	cout  << p.x << "," << p.y << endl;
}