4.15 Foliage don´t loock good
Unreal 4.15 added the ability for Foliage LOD dithering to be disabled on a case-by-case basis by unchecking the Dithered LOD Transition checkbox in the foliage materials. Note that all materials used on all LODs need to have the checkbox checked in order for dithered LOD transitions to work. When checked the transition of generated foliage will be a lot smoother and will look better than 4.14.
I haven't tried this out myself yet, but enabling the checkbox for every piece of foliage should make your foliage look even better than in 4.14! If you find out how to 'mass enable' this checkbox, please report back here for future reference.
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