EQ knobs in LateNight PaleMoon look different with Qt6.5.3

[JoergAtGithub]

Bug Description

In Qt6 builds, an additional light grey circle appears on the bigger mixer knobs, but not on the effect knobs.

Knobs in Mixxx 2.4 (Qt5):

Knobs in Main (Qt6.5.3):

Version

Main

OS

Windows 11

[ronso0]

I can not confirm this with Qt 6.2.3 Knobs look indentical.
Which Qt version do you use?

However, the template looks different than the rendering.
Might very well be that the current rendering is the result of a Qt bug which was fixed in your version, and now it is rendered correctly.

[JoergAtGithub]

I use Qt6.5.3 from our VCPKG buildenv.

[acolombier]

What would be the suggested fix here? Change the SVG so it keeps the "rendering bug" on newer Qt version or change it so it looks like expected on older Qt version?

[ronso0]

Change the SVG so it keeps the "rendering bug" on newer Qt version

Not sure how to do that 😆

The "fun part" of styling the knob SVGs was always trial, error, trial error ... because they were alomst never rendered like how it looked like in my editor (Inkscape) espacially if gardients AND transparency were involved.

change it so it looks like expected on older Qt version

👍
we need to test this with various Qt6 versions (Qt5 compatibility has no prio for 2.5++ IMHO)

[acolombier]

I just had a play and it looks like the rendering bug is caused by the linearGradient referencing the other linearGradient, due to the multiple transform. Seems like the side effect is that it changes the z-index and render above the the black and grey stroking. If you remove the gradient and use a flat colour, this is the closer option I could get on Qt 6.2.4

[ronso0]

Looking at the bug description again ( 🙄 ), the effect Meta knobs still look good.
So actually we Just ™️ need to scale up this smaller knob.

[acolombier]

I've changed my skin setting to have the super knob as well and remove the main mixer which was shifting component. I've used @JoergAtGithub's visual to compare the two looks. Besides fonts and colour tone (likely due to screen colour correction), I think this looks pretty good?

Kooha-2024-05-14-15-55-47.mp4

[acolombier]

@ronso0 do you think the above is a good enough fix? Should I create a PR for it?

[ronso0]

In the gif you posted the EQ knobs look exactly as in the Qt6.5.3 screen @JoergAtGithub posted in the description.
Am I missing something?

[acolombier]

Yes, this is a fade between Qt6.2.4 with my fix and @JoergAtGithub 's screenshot

Edit: Actually, it starts with Joerg's version, fade to my fix on 6.2.4 and fade back to Joerg's

[ronso0]

Sorry, I don't see a relevant difference. The ring is still there with const color, no gradient / fading to bg color top->bottom.

[ronso0]

I can try to scale the small knobs up and share that, but I can't test since I'm still on Qt 6.2.3 (where knobs look like they do with Qt5).

[acolombier]

I'm confused now, I though the look on Qt 6.5.3 was the one we wanted to keep, is that the other way around?

[Swiftb0y]

No, we wanted to keep the consistent Qt5 look (the one where it looks like the button are being lit from above and throwing a shadow below).

[ronso0]

Yep 😄 we want to keep the skeumorphic look from 2.4, with the gradients, soft edges etc.

So, since the small knobs (fx Meta knobs) still look as desired, I assume something in the big knob's SVG is broken/incompatible/Qt quirk fixed/new Qt bug that prevents the soft rendering from Qt 6.2.3 and earlier.

That's why I suggested to clone the small knobs and carefully scale the elements up (maybe shift/resize/reposition the gradients) to get the old look. (this assumes the knobs look as desired in the respective SVG editor, which they do for me in Inkscape 1.3.2 on Linux)

[JoergAtGithub]

@ronso0 I guess a fix for 2.5.0 is too risky?

[ronso0]

I'll try upscaling the intact effect parameter knob today and provide a commit for testing.

Testing should be straight forward, I don't see a risk. Would be really good shipping 2.5.0 with a nice GUI, this simply slipped off my TODO list.

[ronso0]

@JoergAtGithub could you please post a screenshot of the knobs in the Main/Headphone mixer?

I tried upscaling the fx knob but more tweaking is required to get the Qt5 look.
If the Main knobs look okayish I could work off those.

[JoergAtGithub]

Latest Mixxx 2.5 Qt6.5 100% system scaling:

Latest Mixxx 2.5 Qt6.5 150% system scaling (Windows default for my screen):

Latest Mixxx 2.5 Qt6.5 200% system scaling:

Mixxx 2.4.2 Qt5.15 100% system scaling:

Mixxx 2.4.2 Qt5.15 150% system scaling:

Mixxx 2.4.2 Qt5.15 200% system scaling:

[ronso0]

Okay, thank you!
So the smaller Main and effect Meta/Super knobs are still rendered as desired.

I'll try again.

[ronso0]

@JoergAtGithub did you notice that all knobs are blurred, like being rendered at 100% then being upscaled?
For me, with Qt 6.2.3 everything¹ looks crisp @200%
(and IIRC it also did with Qt5.12.8)

¹except the effect flow indicators (chevrons)

[ronso0]

I start to belive that in your version (6.5 on Windows) the issue is simply that the top (diagonal) gradient with the blur filter is not rendered. Maybe that can be replaced with a ring or whatever.

I'll try to fix this tomorrow or the day after, but it's hard since I don't see the bug. All I can do is try to get the sme look without blur filter and translucent gradient.

Should be (one of) the last 2.5 bugfixes.

[ronso0]

@JoergAtGithub could you please check if this change fixes the appearance (at least the blurry knobs):
https://github.com/mixxxdj/mixxx/blob/2.5/res/skins/LateNight/palemoon/knobs/knob_bg_regular.svg?short_path=e944cb4#L6-L7
change this

   height="34"
   width="40">

to

   height="68"
   width="80"
   viewBox="0 0 40 34">

edit: oh, unlike with buttons this doesn't seem to work for me, knobs are just 1/4 of the size now : /