#include <iostream>
#include <graphics.h>
#include <cmath>
#define PI 3.1415
#define N 5

using namespace std;

int main()
{

    initwindow(800,600);
        int points[]={220,150,320,150,320,250,220,250,220,150};
        int poligon[128];
    drawpoly(5,points);
    delay(2000);
    cleardevice();
    int points1[]={420,350,520,350,520,450,420,450,420,350};
    drawpoly(5,points1);
    delay(2000);
    cleardevice();
    double xc=0, yc=0;
    double hc=0,jc=0;
    for(int i=0;i<N;i++){
            xc += points1[2*i];
            yc += points1[2*i+1];
    }
    xc/=N;yc/=N;
     double cosa = cos(PI/4), sina = sin(PI/4);
    for(int i=0;i<N+1;i++){
            double xi,yi;
            xi = points1[2*i];
            yi = points1[2*i+1];
            points1[2*i]   = xc + (xi-xc)*cosa - (yi-yc)*sina;
            points1[2*i+1] = yc + (xi-xc)*sina + (yi-yc)*cosa;
    }


    for(int i=0;i<2*N+2;i++) poligon[i]=(int)points1[i];
    setcolor(YELLOW);
    drawpoly(N+1,poligon);
    delay(3000);
    float Sx=1.2, Sy=1.2;
	float scal = 0.2;
	for(int i=0;i<N;i++){
            hc += points[2*i];
            jc += points[2*i+1];
    }
    hc/=N;jc/=N;
	while(1)
	{
	    // scalare Sx,Sy
    	for(int i=0;i<N;i++){
			points[2*i]  = hc + (int)((points[2*i]  - hc)*Sx);
			points[2*i+1]= jc + (int)((points[2*i+1]- jc)*Sy);
    	}
    	setcolor(GREEN);
		drawpoly(N,points);
    	char c=getch();
    	setcolor(BLACK);
		drawpoly(N,points);

		switch(c){
			case 27 : return 0;
			case '+': Sx=Sx+1;Sy=Sy+1;break;
			case '-': Sx=Sx-1;Sy=Sy-1;break;
			case ' ': Sx=Sx+scal;Sy=Sy+scal;
			default: break;
		}
		if( (Sx<0.4) || (Sy>4))scal = -scal;
	}

    closegraph;

    return 0;
}