I was just wondering how the terrain maker in unity works. I know how to make terrain but how does the poly count work with it? If you were going to make a low poly game that you wanted to run fast on a slow computer would it be better just to model the terrain in Blender or something with a low count?
“Real” terrains perform much better than a mesh terrain and you get way more features.
To lower the poly count of the terrain, set the “pixel error” value in the terrain settings to a higher value. You can actually see the poly count go up and down in the Game Statistics window.
If you are optimizing for integrated graphics, make sure you do not use more than 4 splat textures, and then also use very conservative billboard distances, maximum mesh tree counts, detail densities and draw distances, etc.
Those things will do more to help on slower machines than reducing the poly count a bunch.
And you can modulate them for different quality settings so better machines get a better terrain, instead of everyone getting a low-quality one.
I see, I hadn’t thought that I could edit the settings (it seams pretty obvious now that I think about it though) 
Thanks for the post!
No realtime terrains by far don’t perform better.
But they offer a much higher degree of detail due to dynamically allocating it, thats why you normally take the hit of it.
But especially heightmap based terrains have some restrictions on what you can do, for example for anything with valley and overhangs, their use is rather restricted, you will need some very good modeller to get models to line up to the terrain texture well enough to not look wrong when creating the overhang etc
The heighmap terrain works with resolution so whatever is near gets more resolution more vertices and what is far away it uses less, apart from that there is is a splat map that you can compbine 4 textures or more in one. The splat map is one texture with 4 distinctive colours (or more ) wherever it sees yellow it throws the yellow texture wherever it sees blue it throws another and so on … This works in the background while you paint the terrain in the editor. IT is a really cool technique to create theoretically an unlimited variation of tiling textures. The other cool thing is that you can place trees and grass and porps just by painting in unity editor . and the trees are super optimized and the grass too. It is very easy though to get carried away and ruin your framerate once and for all …
Yes you can’t create caves with height map terrain , You can always go to one corner of your scene create a cave and teleport there with a nice fade in and fade out plus a few sparkling particles … , and for the entrance of the cave put a few stones or something with vast darkness in the middle … i usually create the concave objects first and then the terrain … then i squeeze them in the terrain , and then i apply the texture around to fit with the model. and if it still looks wrong, you put a bit of grass or a big stone in front !!! I think the trick is to have completely different materials for the cave like stone while your terrain is grass . If you use beast then it will look seamless with the lightmap,
If you want to create a cave on top of the terrain i suggest that you use your floor for the cave and not the heightmap terrain . Just sent you heighmap far down …