[BUG] Rotate tool occasionally stops working until I view object from another angle

When I highlight any object in any viewport (level viewport highlighting actors, blueprint viewport highlighting components, physics asset editor highlighting physics bodies, etc.) and bring up the rotate tool by pressing ‘R’, I see the rotate tool handle on the object. Occasionally, when I try to grab an axis on the rotate handle, clicking and dragging does nothing to the object’s rotation, it looks like I’m not dragging my mouse at all. *I can only seem to get this to work by re-orienting my camera so I’m viewing the object from a different angle and then trying again * without doing anything else. **

This has occurred in dozens of different projects throughout engine versions 4.10, 4.11, 4.12, 4.13, and 4.14, and on different computers. I am utterly dumbfounded that this has not been reported yet as far as I can tell on Answerhub. This has been such a consistent bug for so long…

Hi janimationd,

I attempted to reproduce this behavior but I couldn’t get your results. I have also not experienced this issue while using the engine day to day, which makes me think it could be confined to your system. Have you seen this issue on another PC? If so, what are the exact repro steps starting from a new project template?

I have no idea how to reproduce this behavior unfortunately. It seems to strike randomly and when it does, it persists for quite a while, making it quite frustrating to position objects in my level. I have noticed it on different projects, different computers, and different engine versions. With these projects I have not edited engine source code or anything like that.

My way to “brute force” a fix to the issue when it pops up is to start trying to rotate the object while viewing it from different angles. On one occasion I was able to get it to start working again by changing my viewport’s distance to the object (zooming out).

Update: I was able to reproduce this in a clean project.

Steps:

  1. Create new project in engine version 4.14
  2. Import a custom 3D model as a static mesh
  3. Open the static mesh’s asset
  4. Create a simple collision body
  5. Rotate the collision body along one axis at increments of about 5 degrees at a time, releasing the mouse after each increment
  6. If you try this for a bit at different object and camera angles, you may see the reported behavior start happening. It started happening for me

Here’s a video of the behavior: UE4 Rotate Tool Bug - YouTube

Hmm, I followed your repro steps but I still was unable to reproduce the issue. Maybe it has something to do with the custom mesh you are importing? Could you post a test asset here for me to try?

This has been happening with almost any mesh I import, here’s the asteroid FBX though: Google Drive: Sign-in

Thanks for the asset. I was able to reproduce this behavior internally. I also found JIRA UE-39664 that reports a similar issue and depending on how it is fixed, it may also fix this issue in the process.

Cheers,

TJ