LODGroup inspector slows editor

When LODGroup is visible in inspector (even collapsed) and scene camera is moving, all inspectors are being constantly repainted. This causes issues with features like SHIFT+F (lock camera onto moving object).

It becomes really big issue, when there's many components on the game object, because ALL are repainted every frame.

Simple repro steps:
1) Create empty game object
2) Add 30 components (e.g. BoxColliders, AudioSources)
3) Open profiler, select editor profiling and start profiling
4) Rotate scene view - performance is good
5) Add LODGroup (no need to setup LODs or anything)
6) Rotate scene view - performance is terrible

Problematic code:

Code (CSharp):

1. // UnityEditor.LODGroupEditor
2. public void Update()
3. {
4.     if (!(SceneView.lastActiveSceneView == null) && !(SceneView.lastActiveSceneView.camera == null) && SceneView.lastActiveSceneView.camera.transform.position != m_LastCameraPos)
5.     {
6.         m_LastCameraPos = SceneView.lastActiveSceneView.camera.transform.position;
7.         Repaint();
8.     }
9. }
10.  

My opinion is that this code is here to update LOD "slider" when scene view camera position changes.

How to fix it:
1) When component is collapsed, don't call Repaint
- LOD slider is not visible anyways
- simple modification of code above to detect whether component is collapsed

2) Don't detect position change, detect distance change
- since LOD slider depends only on distance, detecting distance from camera makes sense
- add threshold and repaint inspectors only when change is bigger than lets say 1-2%
- this would completely fix the issue for SHIFT+F lock mode and camera rotation

3) Call repaint with lower frequency
- not ideal - stuttering, but still better than constantly slow performance
- additionally fixes the issue for cases like zooming, panning...

 

Yep, seeing this also

 

The issue is still there and I can confirm that my guess above is correct.

Unity team, please fix this issue.
Simple check for component being expanded would solve the issue for 95% of use cases.