Hi, I am using PCL to load my STL file into a Polygonmesh. My main aim is to group the polygons of same surface into one and extract the point information from it. For example, I have an object with 5 faces (lets say curved faces with many polygons) I want to group the polygons of one face into one mesh by this I have to get 5 different meshes.

I have been searching in the internet for surface reconstruction but all of them are starting from PointCloud data and then Normal estimation, cluster extraction and segmentation. I think since we already have the mesh there is no need for this procedure i guess. I am not sure how to work further with this requirement.

Any ideas would be much appreciated. Thanks in advance.