For version IBM® Informix® 12.10.xC3, we've enhanced our support for spatial data. The most exciting enhancement is support of the round-Earth model. Basically, you can put in two sets of longitude and latitude coordinates and get out a distance or area in meters (or whatever linear unit you want). Here's the official description:
You can now calculate the distance and area for data that is based on the round-Earth model. If your geometries have a spatial reference system that is based on angular units, you can calculate distance and area in meaningful linear units. Specify the appropriate unit of measure to convert angular units to linear units in the ST_Area, ST_Buffer, ST_Distance, ST_Length, and ST_Perimeter functions. You can specify predefined units of measure or define your own units of measure. The SE_Nearest function calculates distance between geometries that are in geographic coordinate systems by applying the linear unit of measure of meters.
Also, we've included the following enhancements:
- You can now transform spatial data between spatial reference systems that are in different geographic coordinate systems. Previously, you transformed data only within the same geographic coordinate system.
- You can now choose from many more predefined spatial reference systems instead of defining most of the systems that you need.
- Informix spatial data types now conform to the OpenGIS Simple Features Specification for SQL Revision 1.1 and the ISO/IEC 13249-3 SQL/MM Part 3: Spatial. The Informix spatial solution is based on the ESRI SDE 10.2 Shape and PE libraries.
See the Spatial Data User's Guide for details.