This appears to have been a secondary area for CC3+ cartographers until recently. However, we've received some queries lately asking whether we know of sources for good symbols (objects) and fills (textures) for such maps. Actually, there's quite a bit of good stuff there already, but some folks haven't found it yet. However, only some of it is free. If you want a good set of tools for such maps, I'd suggest that you:

1) Buy the CC3+ Symbol Set 3 (modern) and install it.

2) Buy the CC3+ add-on Cosmographer and install it.

3) Download the free Cosmographer part of the Dundjinni Archives for CC3+ and install it. (You need Cosmographer first!)

After doing that, your screen in Cosmographer mode will look like this, and you'll have a sound library of the symbols and fills you're seeking:

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