A friend and I were remembering the days of LOGO...
He downloaded an implementation of LOGO and wrote a function to
draw the 'dragon' fractal.
I did them same but in VPython...it is attached here.
-Michael
P.S. - I get some weird screen artifacts when using curves to draw the
fractals, I am assuming this is just a bug in the OpenGL implementation (I
have only tried this in Linux)
## The dragon fractal
##
## The arguements to dragon are the iterations and the "size"
## dragon(iterations,size) size has little meaning since vpython
## autoscales
from visual import *
curr = vector(0,0,0)
dir = vector(0,1,0)
colors = [color.red,color.green,color.blue,color.yellow,color.magenta]
col = color.red
def forward(size):
global curr
global col
global drag
for s in arange(0,size,size/50.):
drag.append(pos=(curr+dir),color=col)
curr = curr+dir
def right(ang):
global dir
dir = rotate(dir,angle=-ang,axis=(0,0,1))
def left(ang):
global dir
dir = rotate(dir,angle=ang,axis=(0,0,1))
def step(iter,size,rev,pc):
global curr
global dir
if iter==0:
forward(size)
return
if rev==0:
step(iter-1,size,rev,pc)
right(pi/2)
step(iter-1,size,1-rev,pc)
else:
global col
if pc==0:
col = colors[(iter%5)]
step(iter-1,size,1-rev,1)
left(pi/2)
step(iter-1,size,rev,1)
def dragon(iter,size):
global drag
drag = curve()
step(iter,size,0,0)
dragon(11,10)
--
/-------------------------------------------------------------\
| Michael Katz-Hyman mz...@an... |
| Pittsburgh, PA USA http://www.andrew.cmu.edu/~mzk |
\-------------------------------------------------------------/
|
