Page MenuHome
Create Task
Maniphest T84705

VSE: snapping source strip right handle will incorrectly offset attached transform strip keyframes
Closed, ResolvedPublicBUG
Actions

Description

System Information
Operating system: Debian 10
Graphics card: Radeon HD 7950 + GeForce GTX 1060

Blender Version
Broken: 2.90.0
Worked: 2.83.3

Short description of error

When extending a strip via snapping of its right handle, if it had an effect strip with keyframes, those keyframes are incorrectly offset beyond the source strip boundaries.

Exact steps for others to reproduce the error
With the attached .blend file, press shift + S to snap the right handle of the source strip to the playhead. It will change the transform strip keyframes to be incorrect.

I also attached a crude PoC patch which fixed my own use case. It's in no case intended to be usable as it is but just a hint at the piece of code probably responsible for the incorrect behaviour.

blender_vse_bug_transform_strip_offset_when_extending_source.blend812 KBDownload

blender_vse_bug_transform_strip_offset_when_extending_source.patch1 KBDownload

Revisions and Commits

rB Blender
D10116rB5501a5de32db Fix T84705: Snapping strip handle offset animation

Related Objects

Event Timeline

Olivier Jolly (zeograd) created this task.Jan 14 2021, 12:06 PM
Germano Cavalcante (mano-wii) changed the task status from Needs Triage to Confirmed.Jan 14 2021, 9:47 PM
Germano Cavalcante (mano-wii) changed the subtype of this task from "Report" to "Bug".
Germano Cavalcante (mano-wii) added projects: VFX & Video, Video Sequencer.
Germano Cavalcante (mano-wii) added a subscriber: Germano Cavalcante (mano-wii).

I can confirm the problem, in fact I don't think the snap on just one side of the strip should affect the f-curve. The behavior would combine better with that of transform.
For a better review of the patch, I recommend submitting it through the https://developer.blender.org/differential/diff/create/

Olivier Jolly (zeograd) mentioned this in D10116: PoC fixing regression introduced in 2.90.0 where snapping handles of a strip incorrectly changes related transform strip keyframes.Jan 14 2021, 10:54 PM

I've created D10116 as advised. I also included the fact that either handle snapping won't change the related strip keyframes.

Germano Cavalcante (mano-wii) added a revision: D10116: PoC fixing regression introduced in 2.90.0 where snapping handles of a strip incorrectly changes related transform strip keyframes.Jan 15 2021, 2:04 PM
Richard Antalik (ISS) closed this task as Resolved by committing rB5501a5de32db: Fix T84705: Snapping strip handle offset animation.Jan 25 2021, 6:00 AM
Richard Antalik (ISS) claimed this task.
Richard Antalik (ISS) added a commit: rB5501a5de32db: Fix T84705: Snapping strip handle offset animation.