This is a “wouldn’t it be nice” post– i.e. a I-don’t-have-time-to-write-it-and-everything-else-on-my-list post. Wouldn’t it be nice if in addition to returning GeoRSS, WFS, OGC, KML, etc. GeoServer returned a POV-Ray file? It could be returned as part of a simple GET post like this:
Vector symbolization could be a POV-Ray approximation of the WFS render styles using coordinates and POV primitives. Also, a PHP script could consume this return, and run a command line version of POV to render the file in a webserver implementation. This second part I’ll probably actually write with just a DEM and image overlay, but it would be cool to have the vector symbolization as well as part of another GeoServer protocol. Of course, I recognize this is not a OGC protocol… . Alternatively, a PHP script to consume WKT and convert it to a POV-Ray file might be easier than incorporating it in GeoServer.
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I’m not sure what the client app would do with it, other than display it as a graphic (unless it had the perspective parameters, and the client app was smarter than your average browser). But just displaying it is ok; there’s lots of good info in a 3d perspective.
If you just want to render a perspective scene, then have GeoServer render a WMS image (with burned-in vectors) and WCS DEM (can it?). Have the web server convert them to something POV-ish,use POV render to an image, and send to the client.
And maybe a parameter like request=GetPerspective or request=GetAnimation would be more appropriate…
If a more “interactive” experience is desired, how about extending VTP’s ActiveX plugin (http://www.vterrain.org/Doc/vtocx.html) to get content from a web server?