I have a high resolution elevation map and need to convert it to XYZ points. Simple conversion generates a lot of points in flat / constant slope areas which are redundant for 3D terrain generation. The goal is to reduce number of points by sampling only the points when there is a significant "break" in terrain surface. This would be equivalent to mesh simplification in other software.
I was looking into filtering points by Terrain Ruggedness Index, but from what I understand this index indicates the uneveness of the terrain, not change in gradient.