How to select a 3d line or point in the editor

Hi. How can I select a 3d line or point (handles) in the editor?
I have used HandleUtility.GUIPointToWorldRay. It is OK for 2d space or projected space like x-z but I want to select elements in any view direction.

To find the target point or line, I compute the distance between the mouse position (world space) and all elements and get the index with min distance, finally checking with some threshold