unit Unit8;
{
This software has been designed and it is
CopyLefted by Han de Bruijn:

                          (===)
                         @-O^O-@
                          #/_\#
                           ###
}
INTERFACE

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ExtCtrls, Grafisch, Contours;

type
  TForm1 = class(TForm)
    Image1: TImage;
    procedure Toetsdruk(Sender: TObject; var Key: Char);
    procedure Scheppen(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

IMPLEMENTATION

{$R *.dfm}

type
  funktie = function(x,y : double) : double;

function macht(x,y : double) : double;
{
  x^y
}
begin
  macht := exp(y*ln(x));
end;

function een(x,y : double) : double;
begin
  een := macht(x,y)-y;
end;

function twee(x,y : double) : double;
begin
  twee := macht(x,macht(x,y))-y;
end;

procedure randjes(beeld : TBitmap; i0,i1,j0,j1 : integer);
{
  Clean up boundaries
}
begin
  with beeld.Canvas do
  begin
    Pen.Width := 2;
    Pen.Color := clWhite;
    MoveTo(i0,j0+1);
    LineTo(i1-1,j0+1); LineTo(i1-1,j1-1);
    LineTo(i0,j1-1); LineTo(i0,j0+1);
  end;
end;

procedure test(f : funktie);
{
  Contouring
}
const
  grens : integer = 40;
var
  i,j,k : integer;
  i0,i1,j0,j1,g : integer;
  x,y,min,max,nivo,ff : double;
  bewaar : array of array of double;
  O : Omtrekken;
  verf : TColor;
begin
  SetLength(bewaar,Wijd,Hoog);
  O := Omtrekken.Create;
  O.Afmetingen(Wijd,Hoog);
  O.Scherm := Form1.Image1.Picture.Bitmap;
  i0 := x2i(0); i1 := x2i(exp(1/exp(1)));
  j0 := y2j(0); j1 := y2j(exp(1));
  min := 10; max := -10;
  for j := j0+1 downto j1-1 do
  begin
    y := j2y(j);
    for i := i0+1 to i1-1 do
    begin
      x := i2x(i); ff := f(x,y);
      if ff > max then max := ff;
      if ff < min then min := ff;
      bewaar[i,j] := ff;
    end;
  end;
  Writeln(min,' < ',max);
  for g := 0 to grens do
  begin
    nivo := min + (g/grens)*(max-min);
    for j := j0+1 downto j1-1 do
      for i := i0+1 to i1-1 do
        O.funktie[i,j] := bewaar[i,j]-nivo;
    O.Rondom(false);
    verf := Grijs(g/grens);
    for k := 1 to O.Aantal do
      O.Schetsen(k,verf,1);
  end;
  for j := j0+1 downto j1-1 do
    for i := i0+1 to i1-1 do
      O.funktie[i,j] := bewaar[i,j];
  O.Rondom(false);
  for k := 1 to O.Aantal do
    O.Schetsen(k,clBlack,2);
  randjes(O.Scherm,i0,i1,j0,j1);
end;

procedure TForm1.Toetsdruk(Sender: TObject; var Key: Char);
{
  On KeyPress
}
begin
{ ClearDevice;
  test(een); }
end;

procedure TForm1.Scheppen(Sender: TObject);
{
  At moment of creation
}
begin
  xmin := -0.1; xmax := exp(1/exp(1))+0.1;
  ymin := -0.1; ymax := exp(1)+0.1;
  TV(Form1.Image1);
  ClearDevice;
  test(twee);
  Form1.Image1.Picture.SaveToFile('project8.bmp');
end;

END.