[pgrouting-users] Wrong results at routing by choosing wrong start/end points?

[Marco Lechner - FOSSGIS e.V.]

Hallo Kai,
>> regarding to http://pgrouting.postlbs.org/wiki/killing_some_bugs
>>
>> by calculating the Route twice by changing start and endpoint ist a 
>> possibility to fix the problem in the triangle-like way at the 
>> screenshot. But does this also work if the points are many crossings 
>> away? Dont' I have to compare four results?:
>>
>> SELECT gid, the_geom FROM dijkstra_sp_delta(
>>      '".TABLE."', ".$startEdge['source'].", ".$endEdge['target'].", 3000)
>> SELECT gid, the_geom FROM dijkstra_sp_delta(
>>      '".TABLE."', ".$endEdge['source'].", ".$startEdge['target'].", 3000)
>> SELECT gid, the_geom FROM dijkstra_sp_delta(
>>      '".TABLE."', ".$startEdge['source'].", ".$startEdge['target'].",
>> 3000)
>> SELECT gid, the_geom FROM dijkstra_sp_delta(
>>      '".TABLE."', ".$endEdge['source'].", ".$endEdge['target'].", 3000)
>>     
> ...when I created the tutorial I was wondering exactly the same but I 
> think it can`t be 
> SELECT gid, the_geom FROM dijkstra_sp_delta(
>       '".TABLE."', ".$startEdge['source'].", ".$startEdge['target'].",
>  3000)
> or 
> SELECT gid, the_geom FROM dijkstra_sp_delta(
>       '".TABLE."', ".$endEdge['source'].", ".$endEdge['target'].", 3000)
> because then the route calculation is only on one edge (and not between the needed two edges).
>   
oh I see, I meant:
calculate the 4 routes from
1. Startvertice from Startedge to  Endvertice from Endedge
2. Endtvertice from Startedge to  Startvertice from Endedge
3. Startvertice from Startedge to  Startvertice from Endedge
4. Endvertice from Startedge to  Endvertice from Endedge

I thought this is what my 4 SQL strings do.

Marco