From: Chris Shea <cmshea@...>
Date: 2008-08-16T06:17:08+09:00
Subject: Re: Wig-Wug Simulator

On Aug 15, 2:20 pm, James Gray <ja...@grayproductions.net> wrote:
> On Aug 15, 2008, at 11:12 AM, Chris Shea wrote:
>
>
>
> > On Aug 14, 9:19 pm, James Gray <ja...@grayproductions.net> wrote:
> >> I have started a Wig-Wug (http://therubyist.com/homework/wig-wug/)
> >> simulator and thrown it on github (http://github.com/JEG2/wig-wug/tree/master
> >> ).  It probably still has issues, but it may be of interest to others
> >> playing with the problem.  It includes a map and a digger class I
> >> wrote that does badly on that map.  Enjoy.
>
> >> James Edward Gray II
>
> > Sorry for the empty message. Hit send WAY too early.
>
> > I mean to send this patch, which lets your game server not crash if a
> > player ends up on the edge of the map:
>
> > 91a92
> >>      return 'E' if x == -1 || y == -1 || x == @width || y == @height
>
> Interesting.  Is this a patch to Map#[]?  I wouldn't think it would be  
> needed, due to lines 46-50 of game.rb.  Am I missing something?
>
> James Edward Gray II

Yes. That was for Map#[]. But taking that out and going back to
game.rb, I added "pp surrounding" after surrounding gets settled, and
you can see that there's something up:

  $ ./bin/wig-wug -w 2 -h 2 ~/Desktop/bots/digger.rb     [15:06:44]
  FO
  OR
  Surprise:  Starts at x=1, y=0.

  Turn 1
  [["E", "E", "E"], ["F", "P", nil], ["O", "R", nil]]
  Surprise:  (down) Reached the ruby.

  Result:  Surprise won.

I think the issue is that Comparable#between? includes both endpoints,
so if a bot is on the bottom edge of the map, the Map ends up asking
for points not on the map. And those will be nil if the player's on
the right edge, and will raise a NoMethodError for nil[] if it's on
the bottom edge.

Subtracting one from width and height when they appear as arguments to
#between? on line 46 of game.rb should actually take care of it better
than what I suggested earlier.

Or am I missing something now?

Chris