Hosting and controlling "dynamic" WMS data in Neatline?

[ejred]

I have a rather open-ended question and I’d be interested in any experiences and perspectives people may have on it (also, if there are better places to ask this, please let me know):

I have a city map I’ve built, using a fairly sophisticated set of layers and styles hosted on Geoserver. The current front-end is a crude home-rolled webpage using Openlayers.

I would like a prettier container for it, one that would allow me to easily put context and analysis around the map, and which would also let me to highlight particular physical locations and attach images and text to them. It seems to me that Omeka and Neatline would in many ways be ideal for this. However, after dipping my toe in, I have the sense I may be bumping up against the limits of Neatline, and I wanted to get people’s thoughts on the best way to proceed.

In particular, my current map has several nifty features I would like to preserve in some form:

1. It presents a dynamic, user-defined, multi-variate choropleth map–that is to say, the user can select from a menu of data variables in three dropdowns (C / M / Y) and the map will be colored accordingly. Thus the data can be explored (and connections between variables adduced) visually. This is implemented using the ENV variable to pass information back to the SLD in Geoserver

2. It uses GetFeatureInfo to allow users to open a popup containing a drill-down of the data associated with the selected city block. This is pretty darn useful to make better sense of the choropleth.

3. My shapefile data is in EPSG:4326 spherical coordinates. If I do not reproject it to the x/y EPSG:900913, then–in my case at least–Openlayers renders the spherical data as a nice oblique angle view of the city. Leveraging this, it has an option for “2D” (900913) and “3D” (4326) views. The 3D view is augmented using an isometric geometry rule in the SLD, so that different city blocks are presented as “buildings” based on variables (density, materials, etc.)

Based on my dinking around so far, I’m not really sure how to accomplish any of these when my map is hosted in Neatline:

1. I don’t see any way to pass back ENV data to the WMS server in order to control the map styling dynamically; nor any mechanism to create widgets so that users can control the relevant variables (?) My experience is that trying to realize a similar effect using transparent overlays will not give the desired result. Clearly one could prepare a fixed suite of canned maps, perhaps treating each as its own exhibit. Still, this would be a pale shadow of allowing the users to choose any possible combination.

2. I didn’t see any mechanism for invoking GetFeatureInfo. I guess in principle I could do some kind of database transfer, turning my shapefile tables into Neatline records. I’m not sure whether that’s the best course of action, however. There will be hundreds of these. I don’t want them to appear on the map as icons, I just want the blocks to be clickable. Also, I DO want to add other Neatline records (which will have icons), corresponding to particular locations, offering images, text and analysis relevant to that spot. Mixing up the two kinds of clickable information doesn’t seem necessarily a good idea (?)

3. I also didn’t see any way to explicitly control the projection used for display, although I found I could control it indirectly by varying what coordinate system is spit out from Geoserver (does not work, however, for an overlay, since it is dependent on the underlying map data).

OK, so that’s where I’m at. What I’m wondering whether my assessment is correct, and how I can get the benefits of Neatline, while also keeping these other goodies?

• Are there widgets, plug-ins, config settings or options floating around, which I’ve not yet found, but which will allow me to do these things?

• Is it typical for people on more complex projects to edit the Neatline code? (I assume this would close the door on upgradability forever?)

• Am I just trying to stretch Neatline beyond its breaking point? Would it be realistic and more advisable to drop Neatline, integrate my own Openlayers-based map page(s) into the Omeka site, and figure out some way for users to click on the map and bring up Omeka records?

Thanks for reading this far!