This is with multiplier set to 50. (Distance based) can now capture all the tiny details (no particular details on this sand though) 
Notice the cracks though.
Still locked at 120FPS. 
You can probably make those cracks go away by fiddling with your displacement direction and also include a height-threshold in your distance falloff so when you get less tessellation, the height also lessens. It’s been a while since I played with this. Can’t be more than a year but it feels like a decade. I’m old :o Glad you got it working!
That should definitely do it! and easy todo. I’m gonna post the results soon. Thanks!
Yea you may even have to fade out the height a bit before the tessellation since it doesn’t hand the change very well.
Of course I could be wrong about this (I haven’t read all the code) but I don’t think crack free tessellation does anything useful. At least I have never seen it do anything in all the years it has existed. I have only seen it break over features.
I have faded out the displacement mapping to 0.5 (so it doesn’t go inwards/outwards) at a radius a little smaller than tessellation and it works great now. No more cracks. 
Geh I can’t believe I didn’t think of fading out the height when I was trying to get this working nicely.
I do remember performance being surprising good even with tesselation up to and over 32 (on AMD 7850) as long as the fade distance was reasonable (with dynamic lighting/shadows).
Another thing that might be a nice idea is masking out tesselation for landscape areas that have lots of grass, never got around to it =
For performance it’s better to use mesh that has some amount vertices and limit tesselation factor to 15. Otherwise AMD based cards are suffering.
Are you guys still using this approach for bypassing the tessellation limit? I’m on UE 4.18 and managed to increase the limit somewhat via this modification to FlatTessellation.ush:
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< CompositeTessellationFactors = clamp( CompositeTessellationFactors, 1, 15 );
---
> CompositeTessellationFactors = clamp( CompositeTessellationFactors, 1, 1000 );
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< [maxtessfactor(15)]
---
> [maxtessfactor(1000)]
However, I’m still hitting some limiter somewhere: the tris tessellate now somewhat more, but when viewed close, the tessellation still stops quite early. I’m working with landscapes. Here’s a landscape viewed straight from above from an altitude of 30cm:
This seems to be the maximum amount of tessellation I can get, no matter how much I crank up the tessellation multiplier (both with adaptive tessellation on or off).
I’m resurrecting this thread because I came across the same problem as @hiili . I was struggling with getting more tessellation on my terrain for hours until I happened upon the answer in another thread. I had my landscape component size set to 1x1 sections and 31x31 quads which was way too low to get good tessellation/displacement results (even at the 15 multiplier limit). All you have to do is go into the landscape mode, select manage, use the dropdown to select change component size, and then increase the section and/or components. Make sure to select “resample” beneath so that any painting you’ve done will remain on your terrain. This can get pretty intensive really quickly so I suggest increasing each of the sizes incrementally until you’re happy with the result. I’ve attached a picture of the window in UE4.
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