# rekursiv gezeichnete Strukturen
# ruft man das Programm so auf, werden alle Strukturen
# übereinander gezeichnet, also nur die Codeschnipsel kopieren
from turtle import *

# Farn
def farn (s):
      if (s > 10):
        pensize(s/10)
        fd(s)
        left(25)
        farn(s * 0.6)
        right(35)
        farn(s * 0.7)
        right(25)
        farn(s * 0.5)
        left( 35)
        back(s)
      else:
        fd(s)
        back(s)

setup(width=400,height=550)
tracer(0)
clear()
left(90)
fd(-260)
farn(160)
#===================================================
# Weihnachtsbaum
def lbaum(gross):
      if gross>10:
            lbaum(gross*2/3)
      seth(210)
      fd(gross+gross/3)
      seth(0)
      fd(gross)
      
def rbaum(gross):
      if gross>10:
            rbaum(gross*2/3)
      seth(330)
      fd(gross+gross/3)
      seth(180)
      fd(gross)
            
def wbaum(x,y,gross):
      park=pos()
      shapesize(1,1,1)
      color("darkgreen")
      up()
      goto(x,y)
      down()
      begin_fill()
      lbaum(gross)
      fd(gross/5)
      rt(90)
      fd(gross/5)
      stamm=pos()
      up()
      goto(x,y)
      down()
      rbaum(gross)
      fd(gross/5)
      lt(90)
      fd(gross/5)
      goto(stamm)
      up()
      end_fill()
      goto(park)
      shapesize(2,2,2)
      seth(60)

setup(height=350,width=350)
tracer(0)
wbaum(0,100,100)
#=============================================
# Grüner Baum
def baum(s,t):
    if t>1:
       fillcolor("brown")
       for i in range(1,3):
           begin_fill()
           forward(s); left(90)
           forward(3*t); left(90)
           end_fill()
       forward(s)
       left(30)
       baum(s*0.6, t-1)
       right(55)
       baum(s*0.65, t-1)
       left(25) 
       backward(s)
    elif t>=0:
       fillcolor("darkgreen")
       begin_fill()
       forward(4*s); circle(2*s); backward(4*s)
       end_fill()
       color("red")
       begin_fill
       forward(3*s); circle(5); backward(3*s)
       end_fill() 
       forward(s)
       left(50)
       color("brown")
       baum(s*0.6, t-1) 
       right(85)
       baum(s*0.65, t-1)
       left(35) 
       backward(s)

setup (width=400, height=400, startx=0, starty=0)
# Fenstergröße
title("Grüner Baum")
# Fenstertitel

tracer(0)
left(90)
width(1)
up()
backward(150)
down()
baum(100,6)
#===================================================
# Schneeflocke
def schneeflocke(laenge):
      for h in range (6):
            fd(laenge)                 # linie(l)
            if laenge>2:
                  schneeflocke(laenge//3)
            back(laenge)
            rt(60)

setup(height=350,width=350)
tracer(0)
schneeflocke (100)
#===================================================
# Kochkurve 
def koch( s ):
    if s < 10:
        fd(s)
        return() 
        
    s = s / 3.0 
    koch(s)     
    left(60)   
    koch(s)    
    right(120)    
    koch(s)    
    left(60)   
    koch(s)      

setup(width=400,height=400)
tracer(0)
up()
goto(-150,90)
down()

koch(300.0)    
right(120)
koch(300.0)    
right(120)
koch(300.0)
#==========================================
# Pythagoras-Baum
from math import *

def quadrat(s):
      for i in range (4):
            fd(s)
            right(90) 
def pythagorasBaum(s):
      quadrat(s)
      if(s>5):
         forward(s)
         left(30)
         pythagorasBaum(s*0.5*sqrt(3))
         right(90)
         forward(s*0.5*sqrt(3))
         pythagorasBaum(s/2)
         forward(-s*0.5*sqrt(3))
         left(60)
         forward(-s)

setup(height=450,width=550)
tracer(0)
up()
goto(50,-150)
seth(90)
down()
pythagorasBaum(80)
#=========================================
# Quadratbaum
from math import *

def quadratbaum(wert):
	if (wert>100/2**(4-1)):
		left(90)
		fd(wert/2)
		rt(90)
		fd(wert)
		lt(45)
		quadratbaum(wert/2)
		rt(135)
		fd(wert)
		lt(45)
		quadratbaum(wert/2)
		rt(135)
		fd(wert)
		rt(90)
		fd(wert/2)
		rt(90)

setup(height=450,width=550)
tracer(0)
up()
goto(50,-150)
seth(90)
down()
quadratbaum(50)

mainloop()