Графика по точкам

unit main;
 
{$mode objfpc}{$H+}
 
interface
 
uses
  Classes, SysUtils, Forms, Controls, Graphics, Dialogs, ExtCtrls, StdCtrls;
 
type
 
  { TForm1 }
 
  TForm1 = class(TForm)
    Button1: TButton;
    Edit1: TEdit;
    Edit2: TEdit;
    Edit3: TEdit;
    Edit4: TEdit;
    PaintBox1: TPaintBox;
    procedure Button1Click(Sender: TObject);
  private
 
  public
 
  end;
 
var
  Form1: TForm1;
 
 
implementation
 
{$R *.lfm}
 
{ TForm1 }
 
procedure TForm1.Button1Click(Sender: TObject);
var x,y:longint;r,n,n1:longint;xc,yc:longint;i:real;
begin
    xc:=StrToInt(Form1.Edit1.Text);
    yc:=StrToInt(Form1.Edit2.Text);
    r:=StrToInt(Form1.Edit3.Text);
    n:=StrToInt(Form1.Edit4.Text);
 
    Form1.PaintBox1.Canvas.Pen.Color:=clBlack;
    Form1.PaintBox1.Canvas.Pen.Width:=3;
    Form1.PaintBox1.Canvas.Pixels[xc,yc]:=clBlack;
    n1:=0;
    while(N<2*PI) do
     Begin
     y:=round(yc-r*sin(2*pi/n1));
     x:=round(xc+r*cos(2*pi/n1));
     Form1.PaintBox1.Canvas.Pixels[x,y]:=clBlack;
     n1:=n+n1;
     End;
end;
 
end.