Re: LOGO-L> short question

[Frank Caggiano <caggiano@atlantic.net>]

If the goal is to RETRACE the line drawn than the two methods mentioned
so far would be what you want.  However if the goal is only to get the
turtle back to the point where the 'fd random 150' was issued than you
could save the turtles position, make "savedPosition pos, and then
sometime later issue a 'setpos :savedPosition. If the heading of the
turtle at :savedPosition is important than save it also. 
make "savedState list pos heading ; setpos first :savedState setheading
last :savedState.

In MicroWorlds the turtle variables (created with 'turtlesown') are
great for saving this type of information.  Create two turtle variables
savedPosition and savedHeading.  Then even with multiple turtles you can
easily save and access the data.  This can be expanded to contain all
manner of turtle specific data; shape, size, etc. 

The turtle variables begin to suggest the power of object oriented
programming. That is the object (in this case the turtle) carries around
it's own state.  Of course here we're only dealing with data, while in a
true oo environment code would also be part of the state.  It is
possible with the turtle variables to attach code as a list and then to
'run' the list.  It can get a bit sticky though.

In MSWLogo property lists can do what turtle variables do in
MicroWorlds.  

Check out the projects at my site, specifically 'motion' for a look at
some of these ideas.

Hope this helps and maybe suggests some areas to explore.

regards
-- 
Frank Caggiano
caggiano@atlantic.net
http://www.atlantic.net/~caggiano
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