Re: [Rails-devel] Automatic route calculation

[alexti <al...@sh...>]

On Tue, 13 Apr 2010 09:17:13 -0600, John A. Tamplin <ja...@ja...> wrote:

> On Tue, Apr 13, 2010 at 1:28 AM, alexti <al...@sh...> wrote:
>
>> I avoid "switch" problem in a different way. My vertex definition is
>> geographical - vertex id is its coordinates. Because of that I can check
>> backtracking differently - my criterion is that two consecutive edges  
>> from
>> the same hex are only allowed if they are joined at the center. This can
>> not be derived from the graph definition formally. Essentially I have
>> additional information in the graph that is encoded in the vertex
>> identifiers.
>>
>
> If I understand you correctly, this will fail for some games with
> complicated tiles -- also, how does it handle multiple cities per tile?

That's possible. This method makes several assumptions I thought would  
cover all existing tiles, but there are plenty of games I am not familiar  
with. There are two main assumptions: (1) every rail track that leaves the  
tile always crosses the tile edge in the middle of the edge and does so at  
the right angle. (2) Every tile can be represented as 7-vertex graph.  
Consequently, there would be a limit of 7 separate cities per tile.  
Multiple cities (by that I mean tiles like "OO" or Toronto tile) are  
handled by assigning different cities to different vertices. There's also  
a boolean option indicating whether the train is allowed to visit  
different cities on the same tile or not (I believe this rule is different  
in different games).

Do you have any tiles in mind that wouldn't fit into these assumptions?