[Freeciv-Dev] Re: "division by zero" error during compilation (PR#1954)

["Ross W. Wetmore" <rwetmore@xxxxxxxxxxxx>]

At 04:41 PM 02/09/13 +0200, Raimar Falke wrote:
>On Fri, Sep 13, 2002 at 10:34:15AM -0400, Ross W. Wetmore wrote:
>> 
>> Note, the poor interface and implementation for the macro is the problem,
>> not anything fundamental.
>
>Yes the implementation was the problem.
>
>> The macro has a clean safe form in the corecleanups which use rotationally
>> ordered directions. Here the interface defines any value which can be
>> wrapped to a 2*pi range or the distinct circular subset of points denoting
>> adjacent tiles in this implementation.
>
>No comment about the rotationally ordered directions.

It is too bad you never really mastered how they work and tune out
at the buzzword stage. The above interface comments apply to the 
array-ordered directions as well with the same benefits, just improving 
the implementation along the same lines as in the corecleanups. 

>> The safe version is also much faster than the "iterate over all
>> possibilities and choose one" approach which clearly has scalability
>> problems extending itself to infinitely wrapped ranges.
>
>We are still talking about DIR_CW? There is no iteration. You may mean
>base_get_direction_for_step?!

Just because you unrolled the DIR_CW iteration into a montrous hardcoded
construct doesn't mean you avoided the "iterate and choose" approach 
or don't have the scalability problems :-).

>       Raimar
>-- 

Cheers,
RossW
=====