Mesh\Delaunay 2.5D (XY plane)
Menu
This tool is accessible via the 'Edit > Mesh > Delaunay 2.5D (XY plane)' menu.
Description
Computes a Delaunay 2D1/2 triangulation on a point cloud.
The point cloud is simply projected in 2D on the (XY) plane. Then the corresponding 2D points are triangulated and the mesh structure is applied to the 3D points.
By default the 2D Delaunay triangulation is done on the cloud convex hull. Therefore CloudCompare will ask the user to specify a maximum length for the triangle edges. This allows to remove the biggest triangles (generally on the boundary) that are not necessarily meaningful. If this value is left to zero, then all the triangles output by the Delaunay triangulation will be kept.
This works very well with rather flat clouds and properly oriented (i.e. with the Z dimension as the vertical one). If the point cloud is not properly oriented but is still rather flat in a direction, you should consider using the other version of this method Delaunay 2D (best LS plane).
Note: for 3D triangulation, refer to the qPoissonRecon plugin.