A little more info as to how this package works?

[georgecoltart]

I'm trying to digest what the inputs are for this. It looks like just what I need...

It looks like the required instantiation vars are a 'provider template' and a 'view'

Is the provider template something like http://[abc].tile.openstreetmap.org/zoom/x/y.png ?

And the view is what kind of data?

Sorry Im a rookie Im not sure if this is obvious.

[georgecoltart]

OK so having found this: Usage: $0 --zoom [zoom] --provider [provider] minX minY maxX maxY

So the (minX minY maxX maxY) variables the tile numbers in the /x/y.png tile URL?

[mojodna]

It's not obvious ;-)

A provider template is what you're thinking: http://a.tile.openstreetmap.org/{z}/{x}/{y}.png (it's the same format as Leaflet, FWIW)

A view looks like this and can be generated using getView, given a center point and desired target image dimensions:

{
  extents: [[-122.737, 37.955, -122.011, 37.449]], // this is an array of extents to support stitching around 180º east/west (the antimeridian).
  zoom: zoom // e.g. 12
};

minX minY maxX maxY in the command line tool are geographic coordinates. San Francisco looks like: -122.737 37.955 -122.011 37.449

[georgecoltart]

Great, thanks for clarifying. I'm having a nightmare getting Canvas installed but looking forward to giving this a go.

[mojodna]

What platform? It's definitely painful, but I've had success on OS X with brew install cairo followed by PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/opt/X11/lib/pkgconfig npm install.

[georgecoltart]

Im on a mac, I've got Cairo installed OK. I think it's a broken link to jpeglib.h that's causing me problems, I've posted it here: https://github.com/LearnBoost/node-canvas/issues/348 Don't suppose you know where the jpeglib is supposed to live in relation to the canvas install?

[mojodna]

Weird. Which OS X version? I've had more problems with Cairo on 10.7 than 10.8, but did get it to install (mainly by adding more stuff to PKG_CONFIG_PATH, which doesn't look like your problem here).

If you installed jpeg with homebrew, I would expect to see the header in /usr/local/include.

[georgecoltart]

Thanks for your help with that one.. I now have the server up and running, do I need to construct a URL @ http://0.0.0.0:8080/ with the provider and extent params you mentioned above?

Sorry I'm not a Node dev, I'm not sure if this is obvious stuff or not...

[mojodna]

Sure, no problem.

What are you trying to achieve?

If you're running the server, you can skip the bit about provider URLs and use one of the ones present in providers.json (and/or add your own provider to that).

Here's an example:

http://localhost:8080/mapimg?w=1500&h=1500&extent=37.955:-122.737:37.449:-122.011&p=trees-cabs-crime

That will produce a 1500x1500 image of trees, cabs, and crime for San Francisco (that particular style only covers SF). Note that the coordinates in the extent in the URL are latitude/longitude (where they're x/y when using it programmatically).

There's a second endpoint that accepts an extent and a zoom and will produce an image of whatever dimensions are correct:

http://localhost:8080/?zoom=12&extent=37.955:-122.737:37.449:-122.011&p=trees-cabs-crime

[georgecoltart]

Superb, I'm up and running now. My end goal is print-focussed, so this is ideal for generating my base layer. I was trying this with Mapbox but they have a tight restriction on their static map API (640x640), hence me looking for a self managed solution...

One thing I noticed on the JPEG maps is that I get a

Wrong JPEG library version: library is 90, caller expects 80

GMBP:mapstitch georgecoltart$ brew list jpeg
/usr/local/Cellar/jpeg/8d/bin/wrjpgcom
/usr/local/Cellar/jpeg/8d/bin/rdjpgcom
/usr/local/Cellar/jpeg/8d/bin/jpegtran
/usr/local/Cellar/jpeg/8d/bin/djpeg
/usr/local/Cellar/jpeg/8d/bin/cjpeg
/usr/local/Cellar/jpeg/8d/include/ (4 files)
/usr/local/Cellar/jpeg/8d/lib/libjpeg.8.dylib
/usr/local/Cellar/jpeg/8d/lib/ (2 other files)
/usr/local/Cellar/jpeg/8d/share/man/ (5 files)

Will I have to downgrade my version of JPEG? It looks like I have 8 installed, are you getting this your end after your recent updates?

[mojodna]

Hmm.. I'd reinstall jpeg if you haven't already. (And possibly reinstall cairo after, to make sure that it's linked properly.)

[almccon]

@mojodna The second endpoint you mention doesn't work right for me. If I run http://localhost:8080/mapimg?z=12&extent=37.955:-122.737:37.449:-122.011&p=toner I get a squashed image using the default 1500x1000 dimensions. It doesn't return an image of appropriate size using the native pixel size of the tiles at that zoom.

If I change the zoom parameter, I still get the same map.

[mojodna]

tl render is another option here. (There are probably more, but that's the version I've worked on most recently; when wrapping around the antimeridian, use values outside [-180, 180], as it doesn't contain logic to do that yet.)