Hi, I’m trying to make a floating island with terrain. General idea is I want to cutoff some parts of the terrain which vertex height is below a constant (eg. y <= 0). I stucked at the point where I saw the limit of terrain system that the generated mesh is always square. Is there anyway I can achieve this?
I also looked into customizing terrain shader to not render some of these vertices instead of cutting them off but I’m not a shader guy so I’m not sure how to approach this solution.
Thanks
Honestly, I would approach it by not using Terrain. Use a mesh instead (created in your favorite 3D modeling program, or possibly with the new built-in ProBuilder tools, though I haven’t explored those much myself yet).
Thanks for your reply.
I’m trying to make procedural generated islands so I need to find a way in Unity. I know that I can create meshes at runtime but terrain editor has some useful built-in features eg. Alpha maps, LOD. So it would be great if it’s possible to use terrain in this case.
Hi- this is not possible with Terrain, however you could definitely use ProBuilder + Polybrush to achieve what you want. Or perhaps create a Unity Terrain for the “major” part of your island, then ProBuilder/Blender/etc to construct an edge around the island. 
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