[OpenLayers-Users] Tiling Map Services

[Jon Blower]

Hi Christopher,

Thanks for this reply.

> There is nothing difficult about adding another data source of the form
> you describe to TileCache: it's simply a new layer type. TileCache
> doesn't care about the data, just that it's regular.

I still can't quite see how this would work.  I need to cache data,
not images, so I guess I would need to add tile rendering code to
TileCache in order to turn the cached data into images.  This could be
problematic as my tile rendering code is in Java, but TileCache is in
Python.  Unless TileCache can work with Jython?  This would require
TileCache to be compatible with Python 2.1 (or 2.2 at a push).

Having said this, it's probable that re-implementing the rendering
code in Python will be less effort than trying to replicate TileCache
in Java.

(Should I be having this discussion on the TileCache mailing list?
Apologies if so)

Cheers, Jon

On 3/22/07, Christopher Schmidt <crschmidt at metacarta.com> wrote:
> On Thu, Mar 22, 2007 at 11:05:19AM +0000, Jon Blower wrote:
> > Hi everyone,
> >
> > Most access to our WMS is through OpenLayers, which creates tiles of
> > images of fixed extents and resolutions.  There are various solutions
> > for increasing the efficiency of tiled map access, including
> > TileCache, Tile Map Service (TMS,
> > http://wiki.osgeo.org/index.php/Tile_Map_Service_Specification) and
> > Tiled WMS (http://onearth.jpl.nasa.gov/tiled.html).
> >
> > I don't think TileCache is suitable for my needs out of the box,
> > because I need to cache data arrays, not images (the client can change
> > the colour scale for rendering the same data into different images).
> > However, TMS and TWMS look like they might work for me.  I notice that
> > OpenLayers has a TMS layer class but, on the other hand, a TMS looks
> > very different to a WMS and therefore it would be significant
> > development effort on my part to create a TMS.
> >
> > Does anyone have a feel for how mature the TMS and TWMS specifications
> > are and how widely adopted (or otherwise) they might be?
>
> TileCache is the only open source tiling server I know of. It serves
> TMS, WorldWind, and WMS tiles if you ask for them. In general, I would
> highly recommend modifying TileCache, rather than writing your own
> reimplementation.
>
> There is nothing difficult about adding another data source of the form
> you describe to TileCache: it's simply a new layer type. TileCache
> doesn't care about the data, just that it's regular.
>
> Regards,
> --
> Christopher Schmidt
> MetaCarta
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> Users at openlayers.org
> http://openlayers.org/mailman/listinfo/users
>


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Dr Jon Blower              Tel: +44 118 378 5213 (direct line)
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