Koch+Sierp

import appuifw as A
import graphics as G
import math

''' Koch Square + Sierpinski Triangle '''

lock,run=A.e32.Ao_lock(),1
w,h=G.sysinfo.display_pixels()
img=G.Image.new((w,h))
def exit():
 lock.signal()
def draw(x):
 if img:canvas.blit(img)

A.app.screen='full'
canvas=A.Canvas(redraw_callback=draw)
A.app.body=canvas
A.app.exit_key_handler=exit

def triangle(x0,y0,x1,y1,x2,y2):
 a=math.sqrt((x1-x0)**2 + (y1-y0)**2)
 b=math.sqrt((x2-x1)**2 + (y2-y1)**2)
 c=math.sqrt((x0 - x2) ** 2 + (y0 - y2) ** 2)
 if (a < 2) or (b < 2) or (c < 2): return
 x3=(x0+x1)/2
 y3=(y0+y1)/2
 x4=(x1+x2)/2
 y4=(y1+y2)/2
 x5=(x2+x0)/2
 y5=(y2+y0)/2

 img.line([(int(x3), int(y3)),(int(x4), int(y4))], color)
 img.line([(int(x4), int(y4)),(int(x5), int(y5))], color)
 img.line([(int(x5), int(y5)),(int(x3), int(y3))], color)
 canvas.blit(img)

 triangle(x0,y0,x3,y3,x5,y5)
 triangle(x3,y3,x1,y1,x4,y4)
 triangle(x5,y5,x4,y4,x2,y2)

def square(ax,ay,bx,by):
 f=math.sqrt((bx-ax)**2 + (by-ay)**2)
 if f < 1:return
 f3=f/3
 cs=(bx-ax)/f
 sn=(by-ay)/f
 cx=ax+cs*f3
 cy=ay+sn*f3
 h=f3*math.sqrt(3)/2
 dx=(ax+bx)/2+sn*h
 dy=(ay+by)/2-cs*h
 ex=bx-cs*f3
 ey=by-sn*f3
 triangle(cx,cy,dx,dy,ex,ey)
 square(ax,ay,cx,cy)
 square(cx,cy,dx,dy)
 square(dx,dy,ex,ey)
 square(ex,ey,bx,by)

cw=ch=w/2
r=cw
off=270.0*math.pi/180
a = (2 * math.pi / 3)
color=0xfffeef

img.clear(0)
for k in range(3):
 x0=cw+r*math.cos(a*k+off)
 y0=ch+r*math.sin(a*k+off)
 x1=cw+r*math.cos(a*(k+1)+off)
 y1=ch+r*math.sin(a*(k+1)+off)
 square(x0,y0,x1,y1)

x2=cw+r*math.cos(a+off)
y2=ch+r*math.sin(a+off)
triangle(x0,y0,x1,y1,x2,y2)

img.save(u'e:\\kochsierpinski.png')
lock.wait()