Decimate Mesh

Mesh DecimateMesh(Mesh mesh, float vertexReductionRate)

Generates new mesh with reduced vertex count.

vertexReductionRate - Vertex reduction percentage value in the range of 0.001% and 100%.

Note, Terrain To Mesh uses UnityMeshSimplifier (MIT License) for mesh decimation that may not be the perfect vertex reduction tool for the flat surfaces.