Thanks, @Helvetosaur, for the suggestion. However, to be honest, that data doesn’t seem to add anything. With the HGTs, I already have that. In the meantime, I find VTBuilder to be quite a nice tool to generate height maps. When importing HGTs, it puts them in the right position on a world map. I then select a region with the Area Tool, and Sample Elevation then allows me to merge the area that I selected into one rectangular layer. This layer I export to BMP, and then it’s ready for
Now, I’m looking for areal images as texture.