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The progress bar should accelerate as it nears completion
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There exists a body of empirical evidence that suggests users have a preference for progress bars that accelerate as they near completion. The same body of evidence suggests that any pauses in the progress process, but especially late pauses, have a profound negative impact on how users experience the process as a while.

The best paper on this subject is

So the progress bar should ideally accelerate and never stops.
Some things we could do to achieve this are:

  • Make the loading of VisualEditor correspond to the first 40% of the progress bar, giving us the remaining 60% as breathing room.
  • If everything loads super-fast, then the remaining 60% are filled in instantly.
  • If a part of the loading process starts taking long, we can start utilizing the 60%.
  • As a last resort, slow down progress exponentially in lieu of pausing.

The 40% / 60% numbers are guesses; some experimentation will disclose the best values.

Event Timeline

ori created this task.Apr 6 2015, 12:41 AM
ori assigned this task to Esanders.
ori raised the priority of this task from to Needs Triage.
ori updated the task description. (Show Details)
ori added a project: VisualEditor-Performance.
ori added a subscriber: ori.
Restricted Application added a project: VisualEditor. · View Herald TranscriptApr 6 2015, 12:41 AM
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The only problem here is the second half corresponds to the converter which is slow because of heavy client-side computation so it may be unavoidable to have any animation stutter.

Tried and failed to add this to the #OriLivnehMindControlDept project.

Change 209869 had a related patch set uploaded (by Esanders):
Improve progress bar

Jdforrester-WMF triaged this task as Medium priority.May 11 2015, 3:03 PM
Jdforrester-WMF set Security to None.
Jdforrester-WMF edited a custom field.

Change 209869 merged by jenkins-bot:
Improve progress bar

Prtksxna added a subscriber: Prtksxna.EditedNov 16 2015, 11:18 AM

Would it be helpful to add this functionality in ProgressBarWidget's setProgress method? An interpolator like the ones in the paper?