Yes, Quadspinner Gaea was very helpful.
GlobalMapper had first allowed me to define a real world region of LIDAR data about 1.5 square km. Data that was itself classified as “ground” data as well as “unclassified” data (meaning trees) that I exported as two extremely hi res heightmaps. Each of them about 2GB, far too big to do anything with in Unreal.
Gaea allowed me to do two things. One was to take the ground LIDAR tif and view it in 3d, and scale the height and export it as a much smaller heightmap that Unreal’s landscaping tool could use, I think approximately 1500 x 1500 (although the way that Unreal’s landscaping tool works, you do not get to pick the exact dimensions you want, so it was probably more like 1524 x 1524 or whatever Unreal’s landscape system wanted that was close). It also can export an actual mesh model of the terrain.
The other thing Gaea did was to allow me to generate a 1500 x 1500 “tree map” from the unclassified LIDAR data that was a black and white mask that I used with the Unreal Landscape tool to create a tree layer, where the Unreal Foliage tool would only instance where real world trees would be. It looked interesting.
I will not describe the many experiments in landscape texturing that I did based off what I learned in the Robon tutorial, beyond saying that I wanted to go beyond raster satellite imagery which would not have enough texel density to look convincing at human scale.
In other words, I wanted realistic landscape a player could walk across.
But if I were making, say, a flight simulator where the view is at a great distance I would not really have needed Gaea, I would just have gotten the heightmap and raster from Global Mapper, worked with them in Photoshop, and applied them in Unreal Landscaping.
So just be aware that if you do not need to get into true environmental landscape design, you might not actually need Gaea. But it is a really interesting tool with a trial period and all.