[OSM-dev] Hello World

[Michal Migurski]

On Oct 13, 2012, at 5:41 AM, Frederik Ramm wrote:

> Mike,
> 
> On 13.10.2012 00:40, Michal Migurski wrote:
>> * Generalized and merged dual carriageways for mid-zoom labels,
>> * City label placements for low-to-mid zooms generated with simulated annealing,
>> * Route shields based on route relations,
>> * Merged transit points.
> 
> There's often a tradeoff between making a beautiful map and making a current map. I have a feeling that some of the things you mention might actually incur quite a lot of processing time.

That is definitely the tradeoff I have in mind, yes.


> On OSM we're used to have "current" maps. Our default mapnik map updates just minutes after you have made a change. The tile layer guidelines for our front page say "Services maintaining minutely updates preferred, but periods up to two weeks may be acceptable depending on the content of the map."; help.openstreetmap.org is full of "I've made a change why doesn't it show" questions.
> 
> Most of the current techniques for doing stuff like generalization are based on a "give me the full planet file and I'll render it" approach and are unsuitable for incremental updates; i.e. you would have to have a fat machine that generalizes the planet once every night or something.

I was thinking once per week or so, but yeah: the generalized parts would have to be done on an offline basis periodically. It would take longer for changes to migrate to this layer. It fills a need for better-looking, easier to use cartography that isn't just a simple rasterization of the vectors in the database, digitized as they are at a particular scale. It also keeps the present Mapnik layer available for mappers, with its up-to-date content derived from a live change stream.

Up-to-the-week is still quite "current" for most people's needs, and distinct from the up-to-the-minute needs of mappers.

-mike.

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michal migurski- mike at stamen.com
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