Re: [Boost-bugs] [Boost C++ Libraries] #11735: A* Out of Range Error on 2D grid if width or height is 1

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #11735: A* Out of Range Error on 2D grid if width or height is 1
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2018-02-22 14:31:45

#11735: A* Out of Range Error on 2D grid if width or height is 1
-------------------------------+-------------------------------
  Reporter:  willi+boost@…     |      Owner:  Jeremiah Willcock
      Type:  Bugs              |     Status:  new
 Milestone:  To Be Determined  |  Component:  graph
   Version:  Boost 1.59.0      |   Severity:  Problem
Resolution:                    |   Keywords:
-------------------------------+-------------------------------

Comment (by brook@…):

 An even better patch might be the following.  Note that I did not reindent
 the original code to emphasize the substantive change.

 {{{
 --- boost/graph/grid_graph.hpp.orig     2017-01-07 11:43:21.000000000
 -0700
 +++ boost/graph/grid_graph.hpp  2018-02-22 07:20:18.000000000 -0700
 @@ -630,7 +630,8 @@

          // If the vertex is on the edge of this dimension, then its
          // number of out edges is dependent upon whether the dimension
 -        // wraps or not.
 +        // wraps or not, but only if the length is > 1.
 +       if (length(dimension_index) > 1) {
          if ((vertex[dimension_index] == 0) ||
              (vertex[dimension_index] == (length(dimension_index) - 1))) {
            out_edge_count += (wrapped(dimension_index) ? 2 : 1);
 @@ -639,6 +640,7 @@
            // Next and previous edges, regardless or wrapping
            out_edge_count += 2;
          }
 +       }
        }

        return (out_edge_count);
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac10/ticket/11735#comment:3>
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