[mapserver-users] mapcache

thomas bonfort thomas.bonfort at gmail.com
Wed Feb 1 06:56:59 EST 2012


On Thu, Jan 26, 2012 at 19:30, John Callahan <john.callahan at udel.edu> wrote:
> I'm giving mapcache a try but with no luck.  Well, some luck.  The module
> loads fine and the demo (vmap0, http://127.0.0.1/mapcache/demo/wms) also
> works fine.  I see the tiles being generated on disk.  Great.  However, the
> problem comes in with my own data/services.  A few questions may help me
> determine the problem.
>
> - in the source element, how do you define multiple layers?  Comma separated
> or separate <layers> entries?

<layers>layer1,layer2</layers>

>
> - in the tileset element, can you have multiple grid entries?  It doesn't
> seem like it from reading the documentation but the sample tileset shows
> both the "g" and "WGS84" grids.
which doc part does not show this?
http://www.mapserver.org/trunk/mapcache/config.html#tileset

>
> - for cache type attributes, what are the possible values?  The docs show
> several possibilities (disk, sqllite, memcache) but the sample shows
> type="tiff" which is not listed on the doc page.  Can other file extensions
> be used here?
http://www.mapserver.org/trunk/mapcache/caches.html

>
> - when I define a FORMAT with name and type, how does that get used?  I see
> that is called in the tileset but how does that relate to the image type
> under getmap/params/format?

The format is used when recompressing individual tiles after having
cut a larger metatile. It is also used when combining multiple tiles
into a single image for a getmap request. If you want to force a
specific format to be sent to the source wms server when creating a
tile, you can add a <format>foobar</format> to your source definition
(at the same level as the <layers> parameter). Both formats don't have
to be equivalent, it is actually a good idea to request the images in
png from the source wms server even when using a jpeg format for the
the tileset, as this will avoid a double jpeg compression (once on the
wms server, once on the mapcache server) when storing an individual
tile to the caches.

regards,
thomas

>
>
> The doc page I am referring to is
> at http://www.mapserver.org/trunk/mapcache/config.html.  I'm sure I'll have
> other questions as I work my way through.  Thanks for this awesome addition
> to Mapserver!
>
> - John
>
> ***********************************************
> John Callahan, Research Scientist
> Delaware Geological Survey, University of Delaware
> URL: http://www.dgs.udel.edu
> *************************************************
>
>
> _______________________________________________
> mapserver-users mailing list
> mapserver-users at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/mapserver-users
>


More information about the mapserver-users mailing list