High CPU usage issues solved in the Silverlight MultiScaleImage control

Good news for all Bing Maps developers with windows update 979202 solving a major performance issue.

CPU usage is high when you use the Deep Zoom feature in Silverlight 3. This problem occurs when the Deep Zoom feature cannot load or decode a tile. The problem persists even if you minimize the Web browser in which the Silverlight 3 application is running.

This would occur if you had either :

1. a custom tile layer that would return 404 errors when tiles were requested (typical for a simple file system on edge tiles that don’t exist but are still requested by the control) or
2. if you disabled the coverage map of the base layers and zoomed into the non-covered area.

Additionally my tests prove that an additional problem with animations causing the MSI control to redraw have also been solved.

This is great news and allows us to do some clever things with dynamic tile layers and animated icons on the map without major performance hits. I hope to share some of these with you in coming posts.