- Easing function for slide-in changed to InQuad
- Easing function for slide-out changed to OutQuad
- Opacity is now interpolated, too.
Have you tested this with the autohide panel. I doubt it will look good.
We want that for newly appearing windows in the middle of the screen, but not for a window that clearly comes in from offscreen.
Not right now, I am not at home at the moment. I can provide a before/after gif later.
Unrelated to your comment:
The comment here needs to be changed. It says InQuart, as I was experimenting with different easing functions before settling on OutExpo.
It is true, that it may be inconsistent with other animations, as it a quicker (longer distance in the same time) animation in comparison.
I was looking around in the Human Interface Guidelines and didn't find a section about motion. We could create a meta task, which covers motion in Plasma in general. In my opinion most animations in Plasma feel a bit old (I am probably used to faster animations mainly from the Material Design Guidelines).
I looked into this here, as this was the first animation I wanted to change.
I really like most animations in Android (Pie) as they feel modern and polished. I may experiment with AOSP-like animations in the future.
Here you go. It is only 30fps and very small.
The first two are with the old animation. the last three are with the new animation. As I am running on the proprietary nvidia driver it may look choppy, but it runs smooth on my laptop with Intel graphics.
The main problem I see is that it's too rapid, imho. It's not very pleasant to watch how some entity moves too rapidly.
I'd like to see some analysis of what's wrong with the current choice of easing curves, how it can be fixed, and why we picked this easing curve instead of that, so we have a "bigger picture" of what should be done.
I can only speak from experience. I don't know if there are any scientific studies that look at user experience with a focus of animation.
So this is my own opinion:
Animations should be quick and clear. An object should animate in a clearly comprehensible way. That means that an object should not appear out of nowhere. It should rather come from a place the user can't see. As we have four screen borders we could just let the object translate from a screen edge, similar to how one would open a drawer in the real world. Of course this is similar to the Material Design Guidelines as this is about comparing design to the real world. Now to this example:
Let's say we have an application launcher menu in the bottom left of the screen. When I click it I expect it to come out of the lower screen edge on the left. Now thinking in the real world: When I open a drawer it does not fade in and only travel a specific short distance. I can see it open from 0% open to 100% open without any jump. Therefore the application launcher should act like a real drawer. Now let's talk about the timing of the animation. I don't open a drawer in just 150ms like in the slidingpopups effect. These 150ms may be tweaked to a bit longer, while staying snappy. There is a range of time where an animation has the perfect length. But that depends on the distance and easing and should be further investigated.
- Animations should resemble their real world counterpaths (e.g. Sliding Popups -> Opening a drawer in the real world)
- Timing should be investigated
- Timing depends on distance and easing.
I recently set up a proper working environment again and started tinkering with different easings and slide-lengths. I decided to make a compromise between the old animation and the one I proposed before.
So, I've been running your patch for a while and have to admit that disappearing animation looks better. However, I advise you and VDG to analyze (perhaps update hig as well?) our choice of easing curves in default effects, e.g. morphing popups, sliding popups, fade, etc, and based on that pick better curves.
Let's make this InQuad to be consistent with most other animations in Plasma, and conform to the emerging guidelines in D25343.
Whoops. Looks like I forgot about this. I guess there are people here with more time to work on this than me. Thanks for the reminder, though! I would be happy if you or someone else takes over this.
I commented on D25343 about this. Also note the following inline comment. If we decide on (really) "OutQuad" for slide-in and "InQuad" (or "OutQuad" in code), we just need to adjust L467. Maybe we should also add a comment at L506 that the easing curve will be reversed.
Technically the "OutQuad" here turns into "InQuad". In L504 the animation is reversed, which also reverses the easing curve.