CPU usage doubles when hiding waveforms in LateNight-2.1-update

[ronso0]

Reproduce:
- choose LateNight 2.1 skin
- drag waveforms splitter so that you can see the scrolling waveforms
- play a track
> check CPU usage
- collapse scrolling waveforms with splitter
> check CPU usage again (here it roughly doubles on each core)
> spinnies, VU meters & time display become choppy
 (sound still plays without dropouts)

2.2.0-alpha-pre (build master r6459)
Linux 3.14.23-rt20 x86_64

[ronso0 (ronso0)]

In Tango lp:1746110 I could work around a waveform issue (no end-of-track warning without scrolling waveforms) by loading waveforms as Singleton and placing them twice in skin:
1 above decks as collapsible splitter item
2 invisible (height 0px, width 0me) below decks
This workaround doesn't solve this issue in LateNight skin.

Also the end-of-track issue from Tango bug doesn't show up in LateNight 2.1

[Be (be.ing)]

This happens with Deere too.

[ronso0 (ronso0)]

@be Do you mean when you comment them in decks? Because here i can't confirm with Deere. CPU usage is constant, no matter whether the waveforms are in decks or stacked above.

[ronso0 (ronso0)]

@be Sorry, didn't notice the splitter can be dragged to zero height

Fixed in https://github.com/mixxxdj/mixxx/pull/1512

[Swiftb0y (swiftb0y)]

Mixxx now uses GitHub for bug tracking. This bug has been migrated to:
https://github.com/mixxxdj/mixxx/issues/9121