[BUG] Large Differences Between Scroll Factors In A Chart Causes The Notefield to Stutter

48productions commented 1 year ago

Is there an existing issue for this?

[X] I have searched the existing issues and none matched.

Operating System

Windows 10

CPU

Ryzen 5 2600X

GPU

GeForce GTX 660Ti

Storage

No response

Game Version

4.18.1

Game Mode

I was using the editor!

Theme

Outfox: Simply Spud - latest Outfox: Soundwaves - from Outfox 4.19.0 RC01 SM5.1: Simply Love (a really old build)

Describe the problem

Changing from a very large to a very small scroll factor will cause the notefield to stutter in editor and gameplay. This reproduces on 4.19.0 RC01 and SM5.1, along with an older Outfox build circa November 2021 (apologies for not reporting then). Using a 60Hz monitor (I bet this would be more easily noticeable with higher refresh rates).

A few factors seem to influence the severity of this behavior:

A larger difference between scroll factors increases severity (stutters when going from factor 9999 -> factor 0.001/speed 1000 after 1/32nd note, less stutter when coming from factor 5000)
More time between the scroll changes increases severity (stutters when going from factor 1000 -> factor 0.001/speed 1000 after 1/2 measure, more stutter after 1 measure)
A slower BPM increases severity

A higher speedmod doesn't increase severity, but makes the stuttering easier to notice.

Speed changes are useful to keep notes readable, but are not required for reproduction (stutters when going from scroll factor 209715 -> factor 1 after 1.5 measures)

Describe what should happen

In an ideal world these stutters wouldn't happen, but I can't say I'm familiar enough with the engine to know if it's feasible to resolve this or not.

Relevant Log output

ProjectOutfox.MainLog.2023-01-14--12.08.07.log ProjectOutfox-Simply-Potato-SM5.ThemeLua.2023-01-14--12.08.09.log ProjectOutfox.Crash.2023-01-14--12.08.07.log

A demonstration chart and video were posted in the discord.

48productions commented 1 year ago

Update: It's been discovered that this behavior is present in StepP1 (SM5 beta 4, but not in StepPrime. The mystery continues.

Scraticus commented 1 year ago

this is a curious one, has any build of Alpha V been tried to see if it remains?

It likely needs a better calculation or effect to smooth the sudden changes, but let me know mate

TeamRizu / OutFox