Unexpected Glitch Using Override On VC Slider or Simple Desk Fader

The issues found when using the Virtual Console
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AllanR
Posts: 51
Joined: Tue Jun 02, 2015 4:29 pm
Location: Scotland
Real Name: Allan Rhynas

I've been trying out the new "Override" feature of a VC slider, with unexpected results. (QLC+ v4.11.0 on Linux Mint-C v18.2).

The DMX Monitor displays a glitch when a simple cue-list is executed AND a VC slider override is set. I don't have hardware to hand to check this fully, but the DMX Monitor is usually correct. The attached workspace demos the issue, it comprises a simple 4-channel generic dimmer and three scenes: 1) All off, 2) All 50%, 3) All 100%. To reproduce the glitch:

1. Open the sample Workspace, then open DMX Monitor.
2. Select VC tab, switch Operate Mode on.
3. Start the Cue List (looped).
4. With mouse L-click on any fader (e.g. Dim-1.1), raise a little and return to "0". Cross at bottom should now have red background.
5. Observe the DMX Monitor - the overridden channel snaps ON at the end of each scene to the scene value it would have been if not overriden, then decays back to zero at the cue fade-out time.
6. I expected it to remain at the overriden value at all times, in this case zero.
7. Whilst the Cue List is running (looped) select the Simple Desk tab, and observe the fader movements, it displays the fader levels including the glitch.

NOTE: The glitch is still present if manually advancing the Cue List, but is not present if blended+linked cue faders are used to advance the cue list.

A practical usage example would be where you wish to turn off a tungsten fixture mid-performance e.g. flickering due to intermittent connection.

A further observation is that a Simple Desk fader override causes the same glitch to appear on the DMX Monitor. This is confirmed on QLC+ v4.10.5b, Win7.

Have I misunderstood the functionality of slider override operation or is this a bug?
Forum-issue_Slider_Over-ride.qxw
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siegmund
Posts: 703
Joined: Mon Nov 02, 2015 11:03 am
Location: Germany
Real Name: Lukas

I can confirm this issue using the latest sources on Xubuntu 14.04 64Bit.
mlohrey
Posts: 243
Joined: Mon Apr 20, 2015 5:07 am
Real Name: Mark Lohrey

This is an issue identified here:

viewtopic.php?f=18&t=10004&start=60

At this stage there is no solution.

As shown by this diagram created by Massimo
https://docs.google.com/drawings/d/1KGh ... sp=sharing
Fades are processed last in the chain of events and create the anomaly you have discovered.

I am sure Massimo is considering a better implementation of fades in Version 5 as it would also solve some other fade related issues for those of us who are theatre users ;-)
AllanR
Posts: 51
Joined: Tue Jun 02, 2015 4:29 pm
Location: Scotland
Real Name: Allan Rhynas

Thanks for the confirmation. Yes it's best to focus on QLC+ 5 development, but at least I understand what's going on.

On the positive side, the Override feature is still very useful for tweaking live scenes then DMX dump of new values. Previously only intensities could be raised, now they can be lowered too. Really good for theatre use.
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