Как нарисовать фрактал



Автор: http://www.swissdelphicenter.ch

procedure DrawMandelbrot(ACanvas: TCanvas; X, Y, au, bu: Double; X2, Y2:
Integer);
var
c1, c2, z1, z2, tmp: Double;
i, j, Count: Integer;
begin
c2 := bu;
for i := 10 to X2 do
begin
c1 := au;
for j := 0 to Y2 do
begin
z1 := 0;
z2 := 0;
Count := 0;
{count is deep of iteration of the mandelbrot set
if |z| >=2 then z is not a member of a mandelset}
while (((z1 * z1 + z2 * z2 < 4) and (Count <= 90))) do
begin
tmp := z1;
z1 := z1 * z1 - z2 * z2 + c1;
z2 := 2 * tmp * z2 + c2;
Inc(Count);
end;
//the color-palette depends on TColor(n*count mod t)
{$IFDEF LINUX}
ACanvas.Pen.Color := (16 * Count mod 255);
ACanvas.DrawPoint(j, i);
{$ELSE}
ACanvas.Pixels[j, i] := (16 * Count mod 255);
{$ENDIF}
c1 := c1 + X;
end;
c2 := c2 + Y;
end;
end;
procedure TForm1.Button1Click(Sender: TObject);
var
R: TRect;
au, ao: Integer;
dX, dY, bo, bu: Double;
begin
// Initialize Mandelbrot
R.Left := 0;
R.Right := 200;
R.Top := 0;
R.Bottom := 205;
ao := 1;
au := -2;
bo := 1.5;
bu := -1.5;
//direct scaling cause of speed
dX := (ao - au) / (R.Right - R.Left);
dY := (bo - bu) / (R.Bottom - R.Top);
DrawMandelbrot(Self.Canvas, dX, dY, au, bu, R.Right, R.Bottom);
end;

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