HandleUtility.ClosestPointToPolyLine and PerspectiveView

Hello,

I am using HandleUtility.ClosestPointToPolyLine() to get the projected mouse position on a 3D polyline.
But the output point doesn't seem to be exact when the scene view uses perspective projection.

For example, with this simple editor:

Code (CSharp):

1. using UnityEngine;
2. using UnityEditor;
3.  
4. [CustomEditor(typeof(MyScript))]
5. public class MyScriptEditor : Editor
6. {
7.  
8.     Vector3[] polyLine = new Vector3[] {
9.         new Vector3 (0.0f, 0.0f, 0.0f),
10.         new Vector3 (3.0f, 0.0f, 0.0f),
11.         new Vector3 (4.0f, 2.0f, 2.0f),
12.         new Vector3 (0.0f, 3.0f, 6.0f),
13.     };
14.  
15.  
16.     void OnSceneGUI ()
17.     {
18.         Handles.DrawPolyLine (polyLine);
19.  
20.         Vector3 mouse = HandleUtility.ClosestPointToPolyLine (polyLine);
21.  
22.         Handles.DrawSolidDisc (mouse, -Camera.current.transform.forward, 0.1f);
23.  
24.         HandleUtility.Repaint ();
25.  
26.     }
27. }

With the scene view in isometric projection, the disc is drawn under the mouse cursor (expected behavior):


But in perspective projection mode the disc is not under the mouse cursor (wrong behavior):


Is there a way to get HandleUtility.ClosestPointToPolyLine() working correctly with perspective projection?

I know there are HandleUtility.PushCamera(), HandleUtility.PopCamera() and Handles.SetCamera() but I don't really understand how to use them and if those methods can help to solve my problem.

 

I have finally decided to fill a bug report, the case number is 694657.