Importing georeferenced mapping raster imagery into the active AutoCAD drawing is being performed by means of few simple wizard-driven steps. The primary use of this wizard is to bring an image into the DWG and adjust the position of the image relative to your model such that the model will lie in the proper scale and position on the earth's surface.

Import Map wizard drives you through the following steps:

1. Specifying area of interest
2. Selecting map provider and type
3. Assigning spatial reference system
4. Raster imagery post-processing
5. Specifying resulting imagery location
6. Resulting raster imagery properties

Raster Imagery Cache

TopoPlanner uses specialized image-caching techniques to provide fastest georeferenced raster imagery access possible. There's specific cache portion (catalog) for each mapping provider, map type and zoom scale. TopoPlanner queries following resources, in particular order provided below, while trying to provide requested map data:

1. Local raster imagery cache - this is the fastest executed query but also quite local in scope, based on imagery data stored on the local computer's hard-disk. Local cache can also get purged completely, or based on specified date span.
2. LAN-based raster imagery cache - it is possible to define network-wide raster imagery cache storage accessible by multiple concurrent users. This capability is a quite bandwidth-saving option for large organizations using centralized, pre-populated  imagery cache.
3. Internet - if there's no results from the queries during steps 1) and 2), TopoPlanner turns to the specified Internet-based mapping provider and fetches the data, populating one of the two previously described caching targets.

Raster cache catalogs are organized into raster pyramids. Raster pyramids are reduced resolution representations of imagery dataset used to improve performance. Pyramid levels consist of raster tiles arranged by scale. Pyramids can speed up the fetching of raster data by retrieving only the data at a specified resolution that is required for the selected area of interest. TopoPlanner chooses the most appropriate pyramid level automatically based on the specified display scale.

Common Map Types

There are "common" sets of map types provided by most map vendors: