Creating a Map with Load-on-Demand

Note Make sure you have downloaded the files into the <wacodir> and <cadrgdir> directories before starting this example.

In this example, you are going to create a map having the load-on-demand functionality. The geographical area is the region of Waco, Texas in the United States. Several files will be loaded:

• The first map file, waco.ilv, is vectorial. It contains the towns and roads of the region. This map file will be visible at any scale and provides the base structure of the map.

• The second file demonstrates the load-on-demand functionality. You will use a CADRG (Compressed ARC Digitized Raster Graphics) scanned map file of the Waco, Texas, region. Its format is especially suited to the load-on-demand functionality and is one supported by Views Maps. The information will be visible according to the scales you set.

• The third file is extremely large and will serve to demonstrate the excellent response times when manipulating a map with load-on-demand.

For further information on the CADRG format, see the section The CADRG File Reader.

This example shows:

• How to create a map using the load-on-demand functionality

• How to enhance a Views file with load-on-demand

• The performance of load-on-demand