File:Кольцо деревьев.png

uses GraphABC;
const
  K1 = 0.99;
  K2 = 0.5;
  K3 = 0.45;
  IncAngle = 15;
  Rotation = 45;
  R1 = 130;
  R2 = 160;
  Iterations = 10;

procedure RLine(x, y, x1, y1: real):=Line(Round(x), Round(y), Round(x1), Round(y1));

procedure Draw(x, y, r, ang: real; toRight: boolean);
begin
  var ang1 := DegToRad(ang);
  
  var cx := x + r * Cos(ang1);
  var cy := y + r * Sin(ang1);
  
  RLine(x, y, cx, cy);
  
  if r > 1 then
    if toRight then
      Draw(cx, cy, r * K1, ang + IncAngle, toRight)
    else
      Draw(cx, cy, r * K1, ang - IncAngle, toRight);
end;

procedure Draw(x, y, r, ang: real);
begin
  Draw(x, y, r, ang, true);
  Draw(x, y, r, ang, false);
end;

procedure DrawTree(x, y, r, ang: real; iterations: integer);
begin
  var ang1 := ang;
  ang := DegToRad(ang);
  
  var cx := x + r * Cos(ang);
  var cy := y + r * Sin(ang);
  
  var mx := (x + cx) / 2;
  var my := (y + cy) / 2;
  
  RLine(x, y, cx, cy);
  
  if r < 30 then
    Draw(mx, my, r * 0.069, ang1);
  
  if iterations > 0 then
  begin
    Dec(iterations);
    var r2 := r * K2;
    DrawTree(cx, cy, r * K3, ang1, iterations);
    DrawTree(mx, my, r2, ang1 + Rotation, iterations);
    DrawTree(mx, my, r2, ang1 - Rotation, iterations);
  end;
end;

begin
  SetWindowSize(600, 600);
  SetWindowIsFixedSize(true);
  ClearWindow(clBlack);
  
  var W := Window.Width;
  var H := Window.Height;
  
  SetPenColor(clPink);
  
  LockDrawing();
  
  var W2 := W / 2;
  var H2 := H / 2;
  DrawTree(0, 0, R2, 45, Iterations);
  DrawTree(W2, 0, R1, 90, Iterations);
  DrawTree(W, 0, R2, 135, Iterations);
  DrawTree(W, H2, R1, 180, Iterations);
  DrawTree(W, H, R2, -135, Iterations);
  DrawTree(W2, H, R1, -90, Iterations);
  DrawTree(0, H, R2, -45, Iterations);
  DrawTree(0, H2, R1, 0, Iterations);
  Redraw();
end.