Program TP13;
Uses CRT, GRAPH, TP13M;
var p: TPoint;
  c: TEllipse;
  s: TPoly;
  u:real;
  GraphDriver, GraphMode: integer;
Begin
  GraphMode := 0;
  GraphDriver := 0;
  InitGraph(GraphDriver, GraphMode, '');

  p.init(200, 130);
  c.init(200, 200, 100,50);
  s.init(200, 200,'TP13.txt');

  p.show;
  c.show;
  s.show;

  Randomize;

  repeat
   delay(5000);
  u:=u+(random(10)-5)/70;
   s.move(sin(u),cos(u));
   p.move(sin(u),cos(u));
   c.move(sin(u),cos(u));
  until keypressed;

  CloseGraph;
end.

unit TP13M;
Interface
Uses Crt, Graph;
Type
  TLocation = object
   x, y: real;
   constructor init(a, b: real);
   destructor done;
    end;
  TPoint = object(Tlocation)
   Procedure Show; virtual;
   Procedure Hide;
   Procedure Move(a, b: real);
   end;
  TEllipse = object(Tpoint)
   rx,ry:integer;
   constructor init(a, b:real; c, d: integer);
   Procedure Show; virtual;
   end;
  TPoly = object(Tpoint)
   m:array[1..100] of real;
   p:array[1..100] of integer;
   n:integer;
   constructor init(a, b:real; name: string);
   Procedure Move(a, b: real);
   Procedure Show; virtual;
   end;
Implementation
{======}
  constructor Tlocation.init(a, b: real);
   Begin
    x := a;
    y := b;
   end;
  destructor Tlocation.done;
   Begin
   end;
{======}
  Procedure Tpoint.Show;
  Begin
   PutPixel(Trunc(x), Trunc(y), GetColor);
  end;
  Procedure Tpoint.Hide;
   var p: integer;
   Begin
    p := GetColor;
    SetColor(GetBkColor);
    Show;
    SetColor(p);
   end;
  Procedure Tpoint.Move(a, b: real);
   Begin
    Hide;
    x := x + a;
    y := y + b;
    Show;
   end;
{======}
  constructor TEllipse.init(a, b:real; c, d: integer);
   Begin
    TLocation.init(a, b);
    rx := c;
    ry := d;
   end;
  Procedure TEllipse.Show;
   Begin
    Ellipse(Trunc(x), Trunc(y),0,360, rx,ry);
   end;
{======}
   constructor TPoly.init(a, b:real; name:string);
     var F:text;
   Begin
    TLocation.init(a, b);
    Assign(F, name);
    Reset(F);
  n:=0;
    While Not EOF(F) Do
     Begin
   n:=n+1;
      Read(F, m[n]);
     End;
    n:= n Div 2 ;
    close(F);
    Move(0,0);
   end;
   Procedure TPoly.Move(a, b: real);
    var
     i:integer;
    Begin
     Hide;
     x := x + a;
     y := y + b;
     for i:=1 to n do
      begin
       p[i*2-1]:=Trunc(m[i*2-1]+x);
       p[i*2]:=Trunc(m[i*2]+y);
      end;
     Show;
    end;
   Procedure TPoly.Show;
   Begin
    DrawPoly(n, p);
   end;
end.

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