Date: Tue, 13 Aug 2002 08:36:13 -0700 (PDT)
From: Hannah C. Tang <hctang@cs.washington.edu>
Subject: Re: Clarification

The file format comments are somewhat confusing.  Let me attempt 
to recomment it:

  <width> <height> # Width and height of bounding rectangle
  <number of points> # Number of vertices (including the bounding rectangle)
  <number of lines> # Number of edges actually in the maze (does
                    # not include the bounding rectangle)
  <number of rooms> # Number of logical rooms in this maze

  ### Here, we define our vertices
  <x0> <y0> # the first point 
  <x1> <y1> # the second point
... (repeat for all the vertices in the maze) ...
  <x_NumPoints-1> <y_NumPoints-1>

  ### Here we define our edges
  <p0> <q0> <t0> #p0 and q0 are the indices of the points defining 
                 # this edge; t0 is its "openness"
... (repeat for all the edges in the maze) ...
  <p_NumLines-1> <q_NumLines-1> <t_NumLines-1> 

  ### Here we define the our rooms.  This section is slightly 
  ### redundant, but it allows to index into our rooms
  <deg0> # The number of edges adjacent to the 0th room
         <e0_0> <...> <e_deg0-1> # A listing of all those edges
... (repeat for all the rooms in the maze) ...
  <degNumRooms> # The number of edges adjacent to the numRoomsth room
                <eNumRooms_0> <...> <eNumRooms_degNumRooms-1> # etc

  ### Lastly, our start and exit rooms
  <index of start room> <index of exit room>

So, if we are given the following input file:

  50 80 # width and height
  8
  9
  2
  20 40 # points
  0 60
  0 80
  50 80
  50 60
  30 40
  50 0
  0 0
  0 1 1 # edges
  1 2 1
  2 3 1
  3 4 1
  4 5 1
  5 6 1
  6 7 1
  7 0 1
  0 5 0
  6 0 1 2 3 4 8 # rooms
  4 5 6 7 8
  0 1

We get the following maze (the "no wall" edge is represented by the wiggly 
wall).  This picture is *not* to scale:

  ----------
  |        |
  |(room 0)|
  \        /
   \      /
    ~~~~~~
    /     \
   /       \
  / (room 1)\
 /           \
 --------------

Hope this helps.  Let me know if you need further clarification.

Hannah


-- 
There are 10 people in the world:
those that know binary, and those that don't.
	- Anonymous