Smooth Scrolling Targeted For X.Org Server 1.12

[RealNC]

Even if it's fast, there is always a lag. Lag makes it feel sluggish. If you scroll a lot, you spend a significant amount of time waiting for the animation instead of doing what you want to do.

This doesn't happen on my system. Thus my assumption that your system might be slow.

If I scroll with the wheel, the animation stops at the same moment I stop scrolling the wheel. There's no lag, or "catch-up" animation. It's exactly the same speed as with soft scrolling disabled and takes the same amount of time to reach the document position (the slow-down effect at the destination only takes a few milliseconds.)

Thus, you're seeing a different effect than I am.

[BlackStar]

@pingufunkybeat: these patches have nothing to do with what Firefox/IE call "smooth scrolling". Firefox/IE actually do scroll animation, where they render a fake animation for each scroll event that arrives. On top of that, they add some random acceleration/decceleration which make things really ugly (I also prefer disabling this so-called "smooth" scrolling).

These patches do something completely different: they enable continuous scrolling for high-resolution input devices. Imagine a touchpad with gesture support or a mouse with a non-indented scroll wheel that flows smoothly as you rotate it (newer apple/microsoft/logitech mice have such wheels).

The capabilities of these devices cannot be represented under core X. The problem stems from the fact that X11 has historically reported scroll events as discrete, zero-duration button events. This may have made sense originally, but these devices do not work like this: scrolling is a single, continuous motion, rather than multiple discrete events. In other words, if the mouse cursor moves on the x-y plane, scroll events should be mapped to a continuous z axis (or z+w for freely rotating wheels/balls).

Without these patches, the smallest scroll amount possible is 1 line multiplied by you scroll speed setting (typically ~3 lines per scroll event). With these patches, you can now scroll everywhere from 1 pixel to however far you wish.

There is no additional lag. The scrolling is still instantaneous but *extremely* more accurate, because your finger movement now corresponds one-to-one with the scrolling on screen. The result trully is amazing.

Looking forward to this!

[pingufunkybeat]

Even if it's fast, there is always a lag. Lag makes it feel sluggish. If you scroll a lot, you spend a significant amount of time waiting for the animation instead of doing what you want to do.

I scroll when I'm reading, and scrolling animation interferes with reading.

But I guess that the young generation who grew up with GUIs sees things differently and I might be showing my age.

[RealNC]

Then I think it's because your system must be slow or something. Scrolling is very fast and does not slow you down. It's also the reverse of what you say: it *is* a good visual indication of where you land when you scroll the wheel.

Soft scrolling only feels slower on systems that perform this operating in a slow manner, where it feels like GUI lag.

[pingufunkybeat]

In my experience, the lack of this feature is one of the things people use to make fun of just how bad the Linux desktop experience is.

I wouldn't take such people seriously. My gripe with the scrolling is that it makes you slower and you don't have immediate visual feedback of just where you end up once you use the scroll wheel. It was cool back in the 90s, when it was a "wow" factor, but for me, it is annoying. If I scroll a page, I want it to stop scrolling the very microsecond I stop scrolling, and I want to know (by feeling) exactly where I've scrolled to.

This is my gripe with many modern GUIs. You spend lots of time watching animated things and catching them around the screen, when you know exactly where you want them. You spend lots of time reading menus and dialogs and looking for the right thing to click, when you know exactly what the option/file you're looking for is called.

At the same time, you are right that smooth animations in general, when implemented well, can improve usability. So this patch will probably enable some other, better, effects which improve usability. And that's a good thing.

It's just that the "browser scrolling smoothly when you press page down" gimmick stopped being cool about 15 seconds after it was introduced. It slows you down, as it's nauseating to read scrolling text on a monitor.

IMHO, of course.

[elanthis]

It's always great to have new features, but I thought that everybody and their grandma immediately disabled this useless and annoying "feature" within 15 seconds of starting to use a new computer.

In my experience, the lack of this feature is one of the things people use to make fun of just how bad the Linux desktop experience is.

It can be annoying when implemented poorly, but when implemented properly it is a huge usability boost. Animations that illustrate where something that moved has actually gone makes a huge difference in your ability to efficiently use any UI.

(On an off-topic note, this is one of my biggest gripes with the Roku UI. You click a button, there's some lag, a sound, and then your screen is laid out differently. If someone else is using the remote, for instance, it's very disorienting and at times difficult to tell if they're moving left or right through the queue, leading some confusion like "go back to the left... i mean forward to the right... i mean, back to wherever you were, you passed it.")

[GreatEmerald]

Oh wow, I can disable that for the time being. Awesome! Thanks for the tip!

For those who would like to know how: Go to about:config, search for general.smoothScroll and doubleclick it.

[pingufunkybeat]

It's always great to have new features, but I thought that everybody and their grandma immediately disabled this useless and annoying "feature" within 15 seconds of starting to use a new computer.

I refused to use IE long before the browser wars got started precisely for enforcing this dumbass behaviour.

[TheCycoONE]

Assuming the patches are related to this year old thread " http://www.mail-archive.com/[email protected]/msg06390.htm" it has more to do with input event resolution than GUI controls.

Opps, cut off the url and didn't catch it in the edit timeout:
http://www.mail-archive.com/xorg-dev.../msg06390.html

[GreatEmerald]

Awesome, and about time indeed. Lack of it is basically the thing that I dislike the most on my Linux installation so far (followed by very slow Flash performance), so fixing it will go a long way indeed.