2 questions, second one is more important to me.
I have made terrain in World Machine. A diffuse and hightmap both 4k. I use adaptive subsubdivision (2.78) and get decent results in the distance but I can’t seem to get good detail on the ground in front of the character. Should I be using True displacement or Both displacement? Bump seems to work better but seems to make things look artifiact-y, like it’s using sharp shading instead of smooth. I see squares on the ground rather than smooth like it should be?
Second problem. I was hoping to mix a smaller tiled displacement texture into the large displacement to maybe solve the first problem by adding detail the adaptive sub could use. I’ll post a picture of the node setup. I tried MixRGB using multiply, mix and overlay but it didn’t seem to work, the squares from the first problem are still present.
Also just another quick question, is there a way of telling Blender to use less detail in the back and more in the front or is it locked atm?
Thank you and apologies if this is hard to follow, I’ll gladly clear anything up, really stuck on this and it’s holding me back from progressing with my project so ANY help would be extremely appreciated. First time poster long time lurking too 
(extra info: the terrain is 1 kilometer wide (0.6 miles), the node setup is just a rough example of what i’m trying to achieve, it’s not quite working)
