Thanks for your help! I can always count on the pros at DM. :) I'm still a bit unclear about how the 3-D rasters (lat,lon,time) should be set up in the mapfile. Is there a way to define a 3-D layer in the mapfile? Or should I do something similar to what I would to set up the n-D WMS (with a tile-index)?
Thanks! Sam On 10/24/07, Yewondwossen Assefa <[EMAIL PROTECTED]> wrote: > > Samuel Hiatt wrote: > > Can anyone help with this last question? I'm hesitant to start hacking > > at this 'cause I don't really feel like re-inventing the wheel... > > again. Is anyone familiar with the mechanism that is used when > > mapserver gets a WMS request with a TIME parameter? Maybe the solution > > lies there. > > > > > The metadata tags required to make 4D WMS layers work all have "wms_ > > ..." at the beginning. I imagine that extending this functionality to > > any type of mapserver request (WMS, mapscript, CGI) would be very > > valuable (if it doesn't exist already). > > > > As explained earlier, the wms will take the time parameter and > transform it to a valid time expression and set the FILTER element of > the layer with that expression. > > wms_xxx tags are there to hold information so that this tarnsformation > can be done (hold information such as which is the time field on the > layer, extents of valid time, default valid time ...). Most of these > things are specific to the wms specification > > In you case, if you are using scripting, you should do the same > operation of transforming the time parameter to a valid time filter and > set it on the layer (time parameter like 2004-10-12 could be transformed > to (`[time_field]` eq `2004-10-12). Although the underlying code exists > in MapsServer to parse different kind of time values, there are no > currently mapscript functions that would do that for you so you need to > write your functions. > You map file does not need to have any wms_xxx parameters. It is a > regular map file and the time is just another type of expression that > can be used on the FILTER element of the layer (or on the class object) > > Hope this helps. > > Best Regards, > > > Thanks for your help. > > > > Sam > > > > > > > > > > On 10/12/07, *Samuel Hiatt* <[EMAIL PROTECTED] > > <mailto:[EMAIL PROTECTED]>> wrote: > > > > Thanks for the help. > > > > It should be very easy to filter my files for time. What should my > > mapfile look like for the 4D layer? The same thing as for a 4D wms > > layer, with the tile index and wms_* metadata tags but I would use > > mapscript to screen the files? Do you know of a way I might reuse > > the screening code that is used for 4D WMS? > > > > Thanks! > > Sam > > > > > > > > > > On 10/12/07, *Yewondwossen Assefa* < [EMAIL PROTECTED] > > <mailto:[EMAIL PROTECTED]>> wrote: > > > > Samuel Hiatt wrote: > > > Hi! Thanks for the reply. > > > > > > So I suppose when I make a WMS request with TIME Mapserver > > applies the > > > filter behind the scenes, finding which feature in my > > tile_index.shp > > > represents the correct time and then processes the raster > > pointed to by > > > that feature? So if I want to implement the same kind of > > thing with > > > mapscript I'd have to write the filter myself? > > > > > That is correct : assuming that the underlying data can be > > filtered > > using a time field, you need to know the attribute and build the > > time > > expression and set it using mapscript. > > > > > The reason I am interested in doing this is to extend > temporal > > > functionality to ka-map. I may end up abandoning that > > approach and > > > moving to a javascript WMS client (like OpenLayers of > > MapBuilder) instead. > > > > > > Thanks for your help. > > > > > > Sam > > > > > > > > > > > > On 10/11/07, *Yewondwossen Assefa* <[EMAIL PROTECTED] > > <mailto:[EMAIL PROTECTED]> > > > <mailto: [EMAIL PROTECTED] > > <mailto:[EMAIL PROTECTED]>>> wrote: > > > > > > Hi there, > > > > > > The Time parameter that is sent with a WMS request is > simply > > > converted > > > to a time expression and set on the filter object of the > > layer. In the > > > case of wms. the metadata wms_timeitem will be used for > the > > > attribute name. > > > if you are using mapscript, you would need to build the > time > > > expression manually and set the filter parameter. Please > > refer to > > > http://mapserver.gis.umn.edu/docs/howto/wms_time_support > > (section 2.5) > > > to see how time parameters are interpreted. > > > > > > Best Regards, > > > > > > > > > Samuel Hiatt wrote: > > > > I am excited to see that Mapserver supports 4D raster > > layers for WMS, > > > > but I am curious if this functionality can be extended > > to mapscript > > > > calls as well? For example, if I set up a raster layer > > with a TIME > > > > dimension then will it be possible for me to request an > > image for a > > > > specific time with mapscript? Or would I have to do > > this with a > > > WMS call? > > > > > > > > Thanks! > > > > > > > > Sam > > > > > > > > > -- > > > > > ---------------------------------------------------------------- > > > Assefa Yewondwossen > > > Software Analyst > > > > > > Email: [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED] > > > > <mailto: [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>> > > > http://www.dmsolutions.ca/ > > > > > > Phone: (613) 565-5056 (ext 14) > > > Fax: (613) 565-0925 > > > > > ---------------------------------------------------------------- > > > > > > > > > > > > -- > > ---------------------------------------------------------------- > > Assefa Yewondwossen > > Software Analyst > > > > Email: [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]> > > http://www.dmsolutions.ca/ > > > > Phone: (613) 565-5056 (ext 14) > > Fax: (613) 565-0925 > > ---------------------------------------------------------------- > > > > > > > > > -- > ---------------------------------------------------------------- > Assefa Yewondwossen > Software Analyst > > Email: [EMAIL PROTECTED] > http://www.dmsolutions.ca/ > > Phone: (613) 565-5056 (ext 14) > Fax: (613) 565-0925 > ---------------------------------------------------------------- > >
