Sequence Save Thumbnail ignoring Tracks on Spawned Actors

When saving a Sequence that contains a Spawned Actor with tracks such as Transform or Attach, they are all ignored when the Thumbnail is captured. Often this leads to missing actors or misplacements in the Thumbnails making them much less useful. Normal behavior is restored if manual Asset Actions/Capture Thumbnail is used.

Here is a tiny DemoBug project.

[link text][1]

  1. Open Project. The only Level will be loaded.
  2. Open the only Sequence. Note the Thumbnails is already wrong. The Pyramid should be on the right as you see in the level, but it is on the left.
  3. Right Click on the Sequence in Content Browser, Asset Actions/Capture Thumbnail. Now it is correct.
  4. Save the Sequence from the Sequencer tab/Toolbar. The Thumbnail is wrong again. The Spawned Pyramid ignores the Transform Track during Save.

Hello Büke,

I have a few questions for you that will help narrow down what issue it is that you are experiencing.

Quick questions:

  1. Can you reproduce this issue in a clean project?
  2. If so, could you provide a detailed list of steps to reproduce this issue on our end?
  3. Could you provide screen shots of any settings/blueprints/sequences that may be involved?

Dear ,

There are no Blueprints or subsequences used in the project. Note that the correct behavior is available when manually using Asset Actions/Capture Thumbnail. This has to be reproduced by someone who is familiar with the Sequencer and its Attach feature. I am afraid the engineers of Sequencer, just are not doing these basic tests for some reason.

If it will help I will create an empty project with the bug and send it to you. Please let me know.

Dear ,

I created a tiny project that demonstrates the bugs. The bug is actually more generalized. Spawned Actors ignore all Tracks (not just Attach) during Sequence Save thumbnail captures.

  1. Open Project. The only Level will be loaded.
  2. Open the only Sequence. Note the Thumbnails is already wrong. The Pyramid should be on the right as you see in the level, but it is on the left.
  3. Right Click on the Sequence in Content Browser, Asset Actions/Capture Thumbnail. Now it is correct.
  4. Save the Sequence from the Sequencer tab/Toolbar. The Thumbnail is wrong again. The Spawned Pyramid ignores the Transform Track during Save.

The Close Dirty bug:
5. Close the Sequencer Tab. Even though it was just saved, now it is marked Dirty.

Thank you for testing and reporting that last bug.

I hope this helps.

[link text][1]
[1]: 192627-bugdemo.zip (20.3 KB)

I would like a more detailed set of steps as I have not been able to reproduce this issue described in your original post with the information provided. I have set up a sequence with an attached actor track and the thumbnail includes both actors (The actor I used for the initial track and the actor in the attach track). After taking a look at the thumbnail that was generated by default I then followed up with the suggested fix (using capture thumbnail). The resulting image for the thumbnail was not changed.

Thank you for attempting to reproduce the bug. The attachment has to cause a change in world position for it to appear differently in the thumbnail. I have simplified the reproduction and created a BugDemo project. I hope you can see my other replies here.

After taking a look at the project provided, I was able to reproduce this issue on our end. I have written up a report and I have submitted to the developers for further consideration. I have provided a link to the public tracker. Please feel free to use the link provided for future updates.

Link: Unreal Engine Issues and Bug Tracker (UE-47693)

Make it a great day

Thank you! Sorry if this comment will take away the Resolved status. :slight_smile: