I am afraid we don't will be able to import heightmaps in GGMax, at least no atm.
Although we can bring heightmap to GGMax, and work with it as terrain mesh. I myself have some vids about in my thread, forest, wet mud, snowy terrain, mountains, island, etc. But yes, I understand the thread goal, and yes, it would be nice to have a heightmap import feature in GGMax.
Quote: "I'm playing with an editing tool I am writing"
Although the terrain system is undone yet in GGMax, you do fine starting early, so you can analyze all the steps till getting the fully functional terrain system in GGMax, I guess you are saving your tool builds for each GGMax version, just for sake of comparison, and just for debugging purpose, and for your library.
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