[Freeciv-Dev] Re: (PR#3936) introducing native coordinates

[Jason Dorje Short <vze49r5w@xxxxxxxxxxx>]

Raimar Falke wrote:
> On Thu, Apr 17, 2003 at 08:24:58AM +0200, Raimar Falke wrote:
>
>
> > If you want to speed this up you can for example write about
> > iso-maps. Not about your implementation but about iso-maps in
> > general. Why do we want them, what do they look like in various
> > forms and how do they differ from the non-iso maps. This has to be
> > written anyway and you have 2 years of knowledge about this.
>
> I wrote what I learned about this topic down in
> <http://www.freeciv.org/~rfalke/grid_pics2/iso_maps.html> (reading the
> html may be easier). This is mostly for people which haven't thought
> about this topic. I tried to avoid implementation specifics in the
> overview section.
Pretty good.

> Open points in my eyes are:
>  - which form should be default (IMHO per performance)
For performance, non-iso maps are fastest.  But this default should be 
determined by the default view, which is currently iso (iso-view looks a 
lot better on an iso-map, and vice versa).
Using "map coordinates" rather than "native coordinates" as standard is 
fastest, since the vast, vast, vast majority of operations are done on 
map coordinates.
>  - which iso variants do we support (IMHO both)
Hmm?  The "variants" you talk about in the file are just a different 
numbering system; there's nothing fundamentally different between them.
>  - in which form is wrapping defined? Do we support multiple wrapping
>  forms (iso view form and non-iso view form)?
I don't know what this means.  Wrapping is defined for both iso and 
non-iso maps, and is identical in both when done in "native coordinates".
>  - how can mapview code done in an easier way (IMHO with an
>  intermediate form)
Again you are lumping a whole collection of unrelated operations into 
one term.
jason