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Problem: Performance issues related to coordinate system (projection) info

Solution or Workaround

Description

A couple of issues that affects the performance of projections.

Cause

These are known issues.

Solution

Check the map control's coordinate system property. If it is set, a conversion takes place each time the MapLayer is drawn to the screen.

If NADCON support is installed for MapObjects 2.0, then each time a layer with coordinate system info is loaded (from SDE or otherwise), each of the files in the PE_GRIDS directory is accessed. This can be a very slow process (depending upon the client PC), and can be even slower if a virus checker is running on the client. This happens regardless of whether the map control has its own coordinate system set or not. The delay caused by this occurs before the features begin to draw to the screen, but should only happen once (when the layer is loaded).

This latter delay can be avoided at MapObjects 2.0a by renaming or removing
the PE_GRIDS directory.