[josm-dev] HiFi rendering [Was: Hi List!]

[Petr Nejedly]

Raphael Studer napsal(a):
>> Concerning JOSM development, Fred will surely share some ideas. What Fred
>> mentioned a couple of days before at osm-dev was building a cool editor for
>> mobile devices. I recently tried to run josm on a N810. It eat almost all of
>> my resources, dialogs have been to huge and it didn't respond to stylus/mouse
>> press events.
>>
>> I have no clue if Fred already knows that it is impossible at all to make josm
>> running on mobile devices. If not I wonder if it was worth the effort. At
>> least it seems to be very promising to map details such as housenumbers and
>> other POIs live while being outside.
>>
>> Any comments welcome,
> 
> There is an application for mapping: http://www.tangogps.org/
> but it's not a full editor yet.
> 
> Pushing the JOSM forward could also be done by "combining" josm with
> josm-ng (http://svn.openstreetmap.org/applications/editors/josm-ng/).

When we're at this, I have a proof of concept for "HiFi" rendering (locally
only, not committed to josm-ng repo yet). See:
http://stoupa.sh.cvut.cz/~nenik/josm-ng-hifi.png
It is still able to paint large datasets in real time, but much better.

It uses partially ordered painting to get the layered features stand out.
But I haven't yet figured out how to make the transition between layers smooth.
As you can see, there are artifacts between layer=1 and layer=2 segments
(this is slightly modified map over real data in the DB to move the transition
out of the crossroad to verify smooth join on crossroads).

Mapnik doesn't seem to solve this at all (it just put all the outlines at the very
bottom, so you don't see much about the real layering for the same kind of road).
Osmarendered seems to perform the same as me too.
(see  http://www.openstreetmap.org/?lat=50.0414&lon=14.40841&zoom=17&layers=0BFT but
there is the layer change directly in the crossroad - the outline in the crossroad thus
confuses anybody reading the map)

Is there a better approach to this problem? It's about midnight here and I'm loosing ideas...

-- 
Petr "Nenik" Nejedly, NetBeans/Sun Microsystems, http://www.netbeans.org
355/113 -- Not the famous irrational number PI, but an incredible simulation!