I checked Gimp and Fractal Terrain, even though I don't use either one as much as most. I still prefer the Morgensen fractal generator; it's plenty flexible if you can get used to the lack of an interface (command line only).
Raster (bought) [e.g. Photoshop, PaintShopPro, Painter]
Raster (free) [e.g. GIMP]
Vector (bought) [e.g. Illustrator, Corel Draw, Xara]
Vector (free) [e.g. Inkscape]
Vector (Symbol driven) [e.g. CC, Dunjinni]
Online Generator [e.g. City Map Generator, Fractal World Generator]
Fractal Generator [e.g. Fractal Terrains]
3d modelling [e.g. Bryce, Vue Infinite, Blender]
Scanned hand drawn maps
Drawing Tablet and pen [e.g. Wacom]
I checked Gimp and Fractal Terrain, even though I don't use either one as much as most. I still prefer the Morgensen fractal generator; it's plenty flexible if you can get used to the lack of an interface (command line only).
Just to let you know, Waldronate, who mentioned trying Fractal Terrains Pro and Wilbur, is the actual developer to those applications. Might be good to try them out, Wilbur is free by the way.
GP
Gamer Printshop Publishing, Starfinder RPG modules and supplements, Map Products, Map Symbol Sets and Map Making Tutorial Guide
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