Hi, is anyone creating a GIS app with Xith3D. I got questions if your willing to help. Thanks guys.
Roger
Hi, I am about to implement an interactive 3D client for Web Mapping Services. I did simliar stuff a while ago with Java3D but think it’s time to try Xith3D 
!
So I ported my client and am very happy 
about it! I think Xith3D will become a great API (not only for games!). BTW, to all the devs: Two thumbs up!
One crucial point for us will be offscreen and stereo rendering. Any chance to get it up and running in the next couple of weeks/month?
What are you up to, Roger?
gismo
I’m trying to create an enviroment for tracking assets in a GPS based coordinate system. Still gotta get city maps and hopefully some topology data to create height maps, but I’m still in the early phases. For example, I don’t know how to take a map and assign it to a GPS coordinate system. Thats what I’m working on.
Roger
[quote]Still gotta get city maps and hopefully some topology data to create height maps, but I’m still in the early phases. For example, I don’t know how to take a map and assign it to a GPS coordinate system.
[/quote]
There are quite a few GIS packages out there. I am sure you heard about ArcView/ArcInfo which are designed for exactly that purpose. But there are also a lot of other free GIS packages available (you might wanna take a look at http://www.freegis.org. If you are interested in Web Services, check out http://deegree.sourceforge.net/
Do you want to write your own app or are you just interested in getting the maps done? Should it be interactive and/or in 3D?
gismo
No, I was unfamiliar with those. I would like it to be interactive and in 3D. I’d like to box the maps in a cube and texture map weather conditions on the cube sides…but I’m not there yet.
Roger
[quote]I’d like to box the maps in a cube and texture map weather conditions on the cube sides…
[/quote]
I think the most difficult part is getting the data. How to texture cubes is explained in the Xith3D tutorials and examples…
[quote]but I’m not there yet.
[/quote]
happy coding ;),
gismo
Without going into too much detail, I am working on a GIS project in Xith for work. So far we can load terrain data and vector data for overlays like roads, oceans, etc and you can fly around and look at various features. I don’t really see how this applies to Xith exactly, yes we’re using it for GIS, but Xith can be used for anything. If you’re looking for resources, be sure to see www.vterrain.org, there’s a lot of good info there. If you have any questions, ask away…
Also, check NIMA (www.nima.gov) for access to government terrain data. They have VPF and DTED data available.
Thanks, I’ll definitely check out those sites. And I will definitely ask tons of questions. Thanks for you help. I appreciate it.
Roger
Is it possible in xith3D, to scale the coordinate system to GPS coordinates based on the bounding values for a GPS map?
Roger
I am not sure if I understand you right, Roger. Basically you can do pretty much everything within xith or at least with java. You just should be aware what you like to achieve and what the cost for that are.
We are using two approaches related to coordinate systems. The first one scales down the real world coordinates of a map to fit into specified Xith coordinate bounding box (for example a box of 10 units). But be aware that his could lead to problems related to accuracy (z-buffering, collision detecting, picking …). The other one simply maps one real world unit to one unit in xith coordinate space. If you got very high coordinate values, then you should use a org.xith3d.scenegraph.Locale to offset you data.
[quote]So far we can load terrain data and vector data for overlays like roads, oceans, etc and you can fly around and look at various features.
[/quote]
I know that this is not really related to xith, but integrating vector data into the terrain is our next goal. Right now we load terrain data and drape different maps (topology, soil, orthophotos,…) on top of it.
How do you integrate features in your terrain? We are about to implement an algorithm from Lenk (http://www.ipi.uni-hannover.de/isprs-wg2-4/oeepe01_pdfs/lenk_paper.pdf). This algorithm is superfast and looks pretty cool. It “seams” the data into the terrain. Do you use a similar approach or know of other methods to do this?
gismo
When I say “features” I just meant you can fly down and look at the mountains, the roads, that sort of thing. All of the geographic features we have are just textured onto the terrain, which works fine for roads, oceans, etc. We do have “stuff” in the world, represented as 3d models, but they are all mobile and not fixed features. We don’t have cities and things like that, although we can stick a VPF blob on there and say “thats where the city is”. I’d like to have 3d features in the sense you are talking about and the paper you linked too looks like a good start.
As for rogertx’s question, all you need to do to represent very large areas of terrain is to find a mapping into a smaller space. You have to do unit conversions from real world coordinates to 3d world coordinates. These are just static methods in a utility class that do the transform. How complicated that is depends on your requirements in terms of resolution, accuracy, precision, and the types of real world units you’re working with.
It would be nice if there were a toolkit specifically for GIS-related tasks in Xith. It would have, for example, a more robust and customizable Terrain class and maybe loaders for different vector and raster data.