Embedded GIS for census mapping
Figure 1: State Layer Distance between features can be measured. Features can be labeled based on some attribute and text can be splined along the feature. Text (such as title) and other graphics (that are not in the spatial layer) can be added to stress on important events or landmarks with appropriate symbols and thus enhance the readability or take a print. Features can be searched based on attribute values or spatial proximity. Moreover this search can be extended over more than one layer, e.g, one can find all towns within 10 km of national highways. Other spatial layers can be added to the display to enhance understanding (say water bodies or roads layer) and .visibility of layers can be toggled. Symbology of each of these layers can be modified to suit the user's needs. The map contents can be exported to a Windows Bitmap or emf format. It can also be printed. Data The data may reside anywhere on a network. It may be stored in any database that can be accessed through Visual Basic. This is because the current implementation uses MapObjects through Visual Basic. A similar application could be developed with VC++, Delphi and PowerBuilder also.  Fig 2: District Layer Platforms This application is developed in Visual Basic. Currently, it can be added as a plug-in to any existing windows application that can call a DLL.It may be any windows application which is querying a database. The spatial viewing capability is provided through MapObjects. Developed on Windows NT and tested on Windows 95, Windows 98 and Windows 2000  Fig 3: Town Layer Conclusion The stated objective can be met in a number of ways but Visual Basic and MapObjects were chosen for a number of reasons - Visual Basic has a user-friendly GUI. MapObjects is easy to use, seamlessly integrated with Visual Basic application and cost effective. This is meant to be used at many places by many people so licensing issues have to be looked into,hence ArcView was avoided. This is an ideal solution for users who have database applications and want to add a spatial component with a few GIS operations. If the database is very large and better performance is expected in terms of speed at an extra cost, then SDE can be used. In that case, since both spatial and non-spatial data is stored in the same RDBMS, all the RDBMS facilities would be taken advantage of and the application would give enhanced performance. Reference
 Fig 4: Classification of districts based on Total Population Data not available for Jammu Kashmir
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