Re: [Maposmatic-dev] MapOSMatic questions, ideas

[Thomas Petazzoni]

Hello,

Le Wed, 27 Jun 2012 22:30:59 -0700,
Joe Larson <address@hidden> a écrit :

> Since this is my first email to the list, to begin I want to say how
> amazing I think MapOSMatic is and how thankful I am for the skills
> and time the developers who created it have given! I have hung out in
> IRC (as `oeon` typically) and said a couple things in the past - but
> I felt an email was more appropriate now.

Thanks for your nice comments!

> My biggest question is - would it ever be possible for a user to
> submit their own custom style(sheet) during the job creation process
> and if so, what format would this need to be? If custom stylesheet
> upload/submission is not possible - I assume that cloning and setting
> up the project on one's own server is the alternate route, with the
> desired changes to the style. What I am wanting to do is render maps
> for firefighters to display in their stations of their response areas
> - showing some features that don't appear by default with any of the
> current styles and making a few other rendering adjustments for
> visibility. I work for the fire service in a GIS/mapping role.

We would perfectly agree on adding additional stylesheets to the
MapOSMatic service, as long as they are designed to work with Mapnik
2.x and OpenStreetMap data.

Unfortunately, at the moment, we can't provide a way for users to
submit their own custom stylesheet in an on-demand fashion, for each
rendering job. The problem is that Mapnik stylesheets directly contain
SQL queries, so we can't allow users to upload arbitrary stylesheets
without having security problems.

Our hope is to look at technologies like MapCSS, which allows to create
styles in a CSS-like language, which I think would be acceptable to
allow users to upload their own style. However, none of the MapOSMatic
developers so far had the time to investigate those technologies. Any
help or contribution on this would be definitely appreciated.

> A couple other ideas that have come to mind after creating a few jobs:
> 
> It would be good to create the bounding box (bbox) of a job by
> entering corner coordinates - instead of only being able to draw the
> bbox with the mouse. I found that when I wanted to re-print a job,
> but with a different style - I could see the bbox corners in the job
> details, but could not recreate the bbox for a new job by entering
> those coords, only drawing by mouse.

Below the slippy map to select the area, you have 4 small entry boxes,
where you can set the lat/lon of the bounding box corners. You can
change those values, it will not update the slippy map in real-time
(a contribution to implement that would be very welcome!), but if you
do follow the wizard, then those coordinates will actually be used.

> This brings up my 2nd idea - ability to pick a new style and
> regenerate an existing job.

We already have a "Recreate this map" button, but it regenerates the
map with the exact same parameters, including the selected stylesheet.
We would need to think of how to provide a nice UI that allows this, it
is not easy. We want to keep the UI lean and simple, so that "basic"
users can easily find their way. It is difficult to combine that with
the need of more advanced users who want to customize many parameters.

Thanks again for your very useful input!

Best regards,

Thomas
-- 
Thomas Petazzoni                http://thomas.enix.org
MapOSMatic                      http://www.maposmatic.org
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