ó ÑÕfc@sodZddlmZmZddlmZd„Zd„Zd„Ze dkrkeƒZ e GHeƒndS( s— turtle-example-suite: tdemo_tree.py Displays a 'breadth-first-tree' - in contrast to the classical Logo tree drawing programs, which use a depth-first-algorithm. Uses: (1) a tree-generator, where the drawing is quasi the side-effect, whereas the generator always yields None. (2) Turtle-cloning: At each branching point the current pen is cloned. So in the end there are 1024 turtles. iÿÿÿÿ(tTurtletmainloop(tclockccs |dkrœg}x[|D]S}|j|ƒ|jƒ}|j|ƒ|j|ƒ|j|ƒ|j|ƒqWx)t|||||ƒD] }dVqŠWndS(s¤ plist is list of pens l is length of branch a is half of the angle between 2 branches f is factor by which branch is shortened from level to level.iN(tforwardtclonetlefttrighttappendttreetNone(tplisttltatftlsttptqtx((s./usr/lib64/python2.7/Demo/turtle/tdemo_tree.pyRs        cCs¯tƒ}|jdƒ|jƒ|jdƒ|jddƒ|jdƒ|jƒ|jdƒ|j ƒt |gdddƒ}x|D]}qŠWt |j ƒj ƒƒGHdS(NiiiZi.ÿÿÿiÈiAgffffffä?(Rt setundobufferR t hideturtletspeedttracerRtpenupRtpendownRtlent getscreentturtles(RttR((s./usr/lib64/python2.7/Demo/turtle/tdemo_tree.pytmaketree's         cCs%tƒ}tƒtƒ}d||S(Nsdone: %.2f sec.(RR(R tb((s./usr/lib64/python2.7/Demo/turtle/tdemo_tree.pytmain6s  t__main__N( t__doc__tturtleRRttimeRRRRt__name__tmsg(((s./usr/lib64/python2.7/Demo/turtle/tdemo_tree.pyts