uses graph, crt;
type
point=record
       x: integer;
       y: integer;
       z: integer;
      end;
points= array[1..100] of point;
var p, p2 : points;
keskp: point;
num: integer;
nurk1, nurk2: real;

procedure go;
var d, m: integer;
begin
   p[1].x:=0; p[1].Y:=0;   p[1].z:=200;
   p[2].x:=200;  p[2].Y:=0;   p[2].z:=0;
   p[3].x:=0;   p[3].Y:=200;   p[3].z:=0;
   p[4].x:=0;   p[4].Y:=0;   p[4].z:=0;
   p[5].x:=200;   p[5].Y:=0;   p[5].z:=0;
   p[6].x:=0;   p[6].Y:=0;   p[6].z:=200;
    p[7].x:=0;   p[7].Y:=200;   p[7].z:=200;
    p[8].x:=200;   p[8].Y:=200;   p[8].z:=0;
    p[9].x:=200;   p[9].Y:=200;   p[9].z:=200;
   num:=9;
   d:=detect;
   initgraph(d, m, '');
   keskp.x:=getmaxx div 2;
   keskp.y:=getmaxy div 2;
end;

procedure draw(p: points; kp: point; kogus: integer);
var i: integer;
begin
   for i:=2 to kogus do
   begin
    line(kp.x+p[i-1].x, kp.y+p[i-1].y, kp.x+p[i].x, kp.y+p[i].y);
   end;
   line(kp.x+p[num].x, kp.y+p[num].y, kp.x+p[1].x, kp.y+p[1].y);
end;

procedure cir(pp: points; var pp2: points; kogus: integer; x1, x2: real);
var i,k: integer;
begin
  for i:=1 to kogus do begin
      pp2[i].x:=round(pp[i].x*cos(x1)-pp[i].y*sin(x1));
    pp2[i].y:=round(-pp[i].x*sin(x1)+pp[i].y*cos(x1));
    pp2[i].z:=pp[i].z;
  end;
  for i:=1 to kogus do begin
    pp2[i].y:=round(pp2[i].x*cos(x2)+pp2[i].z*sin(x2));
    pp2[i].x:=round(-pp2[i].x*sin(x2)+pp2[i].z*cos(x2));
  end;
end;

begin
   go;
   nurk1:=0;
   repeat
setcolor(red);draw(p2, keskp, num);
   cir(p, p2, num, 0.3, nurk1);
    setcolor(red);
    draw(p2, keskp, num);
    delay(50);
    nurk1:=nurk1+Pi/60;
   until keypressed;
      closegraph;
end.