Changing skin doesn't update every color in the editor timeline

[Gabixel]

Describe the bug: There are 2 (quite identical) ways to reproduce it: 1) Beatmap skin turned off (using skins):

• open the editor
• change skin (I don't know very much about skin colors, but I guess you need a skin that has its own set)
• result: the timeline changes the blueprint color only to nearby objects. If you scroll the timeline, you can notice all distant objects that change their color when scrolling towards them

2) Enabling Beatmap skin:

• similar to the previous way, open the editor with Beatmap skin turned off
• enable it
• (same result)

Screenshots or videos showing encountered issue: (the gif shows the second way)

osu!lazer version: 2020.1005.0

[peppy]

The reason for this is that skin changes are schedule to each individual DrawableHitObject in order to alleviate the load of applying the change. In gameplay this works fine, but in the editor the timeline is showing hitobjects outside of their normal Lifetime range.

Optimally, this would be something we can fix at a Playfield/LifetimeManagementContainer level to simplify things. @smoogipoo thoughts? We could probably add some kind of "LifetimeExtend" or "range" parameter that the editor controls in such cases.

Kind of overlapping behaviour with ScrollingHitObjectContainer, but not confident how this should be structured.

[smoogipoo]

It's not really overlapping, iirc SHOC doesn't handle LifetimeEnd - only LifetimeStart. So yeah maybe having support at LifetimeManagementContainer (which HOC derives from) is a nice way to go about it.

[peppy]

@smoogipoo I guess this may be covered by your incoming changes? Unassigning for now.

[smoogipoo]

Yep, lifetime extensions will cover this.

[peppy]

This has since been resolved.