unit Unit1;

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils, Forms, Controls, Graphics, Dialogs, StdCtrls, ExtCtrls,
  Math;

const FieldWidth = 30; { Ширина и }
  FieldHeight = 25; { высота поля }

type

  TField = array [0..FieldWidth + 1, 0..FieldHeight + 1] of Boolean;

  TPoint = record
    x: Integer;
    y: Integer;
  end;

  { TForm1 }

  TForm1 = class(TForm)
    Screen: TPaintBox;
    StartStopBtn: TButton;
    procedure ScreenPaint(Sender: TObject);
    procedure StartStopBtnClick(Sender: TObject);
  private
    procedure UpdateSurface(field: TField; point: TPoint; neighbours: Integer);
    var Rx, Ry: Integer; { Ширина, высота клекти }
      BlueField, GreenField: TField;
      s, v: Integer;
      bluePoint, greenPoint: TPoint;
  public

  end;

var
  Form1: TForm1;
  IsRunning: Boolean;

implementation

{$R *.lfm}

function CountNeighbours(Field: TField; x: Integer; y: Integer): Integer;
  var i, j: Integer;
begin
  Result := 0;

  for i := -1 to 1 do
    for j := -1 to 1 do
      Result := Result + Ord(Field[x + i][y + j]);
  Result := Result - Ord(Field[x][y]);
end;

{ Выбираем случайную клекту }
function ChoosePoint(): TPoint;
begin
  Result.x := RandomRange(1, FieldWidth);
  Result.y := RandomRange(1, FieldHeight);
end;

{ TForm1 }

procedure TForm1.StartStopBtnClick(Sender: TObject);
  var i, j: Integer;
begin
  if IsRunning then
  begin
    IsRunning := false;
    StartStopBtn.Caption := 'Пуск';
    Exit;
  end;

  StartStopBtn.Caption := 'Стоп';
  IsRunning := true;

  Rx := (Screen.Width div FieldWidth) div 2; { Определяем размеры клетки }
  Ry := (Screen.Height div FieldHeight) div 2;

  Randomize;

  for i := 0 to FieldWidth + 1 do { Очистка поля }
    for j := 0 to FieldHeight + 1 do
    begin
      BlueField[i, j] := false;
      GreenField[i, j] := false;
    end;

  while IsRunning do { Основной цикл }
  begin
    bluePoint := ChoosePoint();
    greenPoint := ChoosePoint();

    s := CountNeighbours(BlueField, bluePoint.x, bluePoint.y);
    v := CountNeighbours(GreenField, greenPoint.x, greenPoint.y);

    Screen.Invalidate;

    Sleep(250);
    Application.ProcessMessages;
    if Application.Terminated then Exit;
  end
end;

procedure TForm1.UpdateSurface(field: TField; point: TPoint; neighbours: Integer);
begin
  if (field[point.x, point.y] = false) and (neighbours > 2) then { Создаем новую инфузорию }
  begin
    Screen.Canvas.Pen.Color := clBlue;
    Screen.Canvas.Ellipse((2 * point.x - 1) * Rx - Rx, (2 * point.y - 1) * Ry - Ry,
      (2 * point.x - 1) * Rx + Rx, (2 * point.y -1) * Ry + Ry);
    field[point.x, point.y] := true;
  end
  else if (field[point.x, point.y] = true) and ((neighbours < 3) or (neighbours > 4)) then { Удаляем }
  begin
    Screen.Canvas.Pen.Color := clBtnFace;
    Screen.Canvas.Ellipse((2 * point.x - 1) * Rx - Rx, (2 * bluePoint.y - 1) * Ry - Ry,
      (2 * point.x - 1) * Rx + Rx, (2 * point.y -1) * Ry + Ry);
    field[point.x, point.y] := false;
  end;
end;

procedure TForm1.ScreenPaint(Sender: TObject);
  var i, j: Integer;
begin
  Screen.Canvas.Pen.Color := clBlue;

  for i := 1 to FieldWidth do { Создаем начальную конфигурацию }
    for j := 1 to FieldHeight do
      if Random(4) = 0 then { В среднем будет одна инфузория }
      begin { на четыре клетки }
        BlueField[i, j] := true;
        Screen.Canvas.Ellipse((2 * i - 1) * Rx - Rx, (2 * j - 1) * Ry - Ry,
          (2 * i - 1) * Rx + Rx, (2 * j - 1) * Ry + Ry);
      end;

  UpdateSurface(blueField, bluePoint, s);

  Screen.Canvas.Pen.Color := clGreen;

  for i := 1 to FieldWidth do { Создаем начальную конфигурацию }
    for j := 1 to FieldHeight do
      if Random(4) = 0 then { В среднем будет одна инфузория }
      begin { на четыре клетки }
        GreenField[i, j] := true;
        Screen.Canvas.Ellipse((2 * i - 1) * Rx - Rx, (2 * j - 1) * Ry - Ry,
          (2 * i - 1) * Rx + Rx, (2 * j - 1) * Ry + Ry);
      end;

  UpdateSurface(greenField, greenPoint, v);
end;

end.