We are considering using ESRI's ArcGIS Engine to write an application with some GIS features. The GIS toolkit features that we are primarily concerned with are:
- 3D visualization: Blend elevation data with raster or vector data.
- Embed GIS functionality within a custom UI / application (QT4 preferred)
- Function without an internet connection (local data caching or geodatabase)
- Create new features (point, line, polygon) and store them in a geodatabase.
- Overlay images over map data and update them frequently.
- Good interoperability with C++
- Cross-platform: Windows, Mac, and Linux
The initial goals for this project are relatively limited, but will likely be expanded in the future -- doing some image processing that incorporates geospatial data, for example.
In addition to ESRI's ArcGIS Engine, we're also looking at using:
- NASA World Wind
- GRASS GIS
It appears that Intergraph has a large number of GIS software products, but it's not yet clear whether they sell an equivalent to the ArcGIS Engine toolkit.
Are there other options worth considering? Insights or opinions on the options already mentioned?
If you can drop the cross-platform requirement for Windows-only, then Manifold System would be a good choice. Very affordable and easy to use with modern development tools on Windows.