I have worked on maps for several years.
Maps are square images and use the circular portion of the image only. The corners are ignored. E3 will accept several formats. I discovered the use of transparent maps, and found ways to work with them. It is a vector method and may not work under certain conditions. None of this is documented and you get what you get.
A couple of maps for your resources. Things seem to standout as maps. I couldn't resist the headlights.
Rich
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