Ground Overlays On Maps

Found a historic map of Boston collected by David Rumsey, and thought it would be nice to be able to put this map on a current map. As the image needs to be scaled, rotated and translated, I wrote a custom symbol (
OverlaySymbol) to enable the scaling, rotation and translation when the map extent changes. So all that is cool, but the problem was coming up with OverlaySymbol properties. So I wrote the OverlayEditor application that enables you to load the image and using a instance of Flex Object Handles, you can stretch, move and rotate the image. Once you are satisfied with the parameters, you can view the source code of a sample application that you can save and compile with a reference to the OverlaySymbol.as code. You can check out the application here. You can load an image of Mount Etna in Sicily. And like usual you can download the source code from here.
Comments
Very help bit of code, am using it to display image overlay of weather data.
However, I'm having a problem in that setting .source = next image to do an animation causes flicker a the old one unloads before the next one is loaded and ready.
I would usually overcome this be using a Loader to download next image and once ready to simply change the content. However, this doesn't work with OverlaySymbol as you actually use a URL on source.
Any ideas?
Cheers
Ian
I downloaded the OverlayEditor zip file and tried to compile it. But it is giving the following syntax errors:
C:\_pelin\programs\flex\OverlayEditor.mxml(65): Error: Attempted access of inaccessible method duplicate through a reference with static type com.esri.ags.geometry:Extent.
previewMap.extent = overlayMap.extent.duplicate();
C:\_pelin\programs\flex\com\esri\overlay\OverlayMap.as(104): col: 17 Error: Attempted access of inaccessible property m_staticLayer through a reference with static type com.esri.overlay:OverlayMap.
m_staticLayer.removeChild(m_objectHandles);
^
C:\_pelin\programs\flex\com\esri\overlay\OverlayMap.as(135): col: 13 Error: Attempted access of inaccessible property m_staticLayer through a reference with static type com.esri.overlay:OverlayMap.
m_staticLayer.addChild(m_objectHandles);
^
I am not sure what I am doing wrong here.