Fading Memories

Warning: no videos included, though they would help a lot. Also note that I'm using an Intel chipset in both my laptops (the big one also has an ATI chipset, but that doesn't work.)

Lukas recently discovered that Krita was taking about 100% of one of his CPU's cores. When moving the mouse over the canvas. Since X11 took about 60% of that CPU we immediately thought of painting issues, so I started testing with KWin's Paint desktop effect enabled. That effect overlays every rect that is redrawn with a color.

It quickly became clear that for some reason, updating the mouse position lable in the statusbar would update all of Krita's window: menu, toolbars, canvas, toolbox, dockers and statusbar. Curiously enough, Karbon only updates the statusbar. When I disabled the mouse position label in Krita, the CPU usage was gone.

Then I started playing some more, also on my other laptop and now in Ersingen for the KPresenter sprintlet, we tried the same on Thorsten's laptop. And I'm puzzled by the results:

On my X61t, the areas covered by the tooltips of the icons in the system tray is redrawn constantly, all on top of each other. If the panel is visible, and I make Krita full-screen, the area covered by the clock, underneath the Krita window, is continuously redrawn. This runs KDE 4.4.62, on OpenSUSE.

On my W500, the whole screen is constantly completely redrawn. No wonder Desktop Effects feel slow on that laptop! If I make Krita full-screen, no matter whether the statusbar is hidden or not underneath the Krita screen, the redraws are gone. This is KDE 4.4.0 rc3, on OpenSUSE.

On Thorsten's T60 (ATI chipset), we don't see the whole-screen redraws, but we do see a rectangle in the middle of the top-left quadrant of his screen, near, but not exactly at, the place where Thorsten keeps his clock that gets redrawn constantly. This is KDE 4.4.0 final.

But when we are testing KPresenter's animation framework, we see that we only redraw the shapes that are moving, so that's good! (Except when two shapes move, then Qt apparently decides to repaint the whole rect that contains the two shapes.

Well, I'm puzzled, so I'm posting this. Obviously minimizing repaints is trickier than I thought, and it seems especially difficult to limit repaints to the minimum necessary.

I'm keeping my promise to write a weekly update on what has happened in Krita. There's usually a lot to write about, and I'm trying to add some generally interesting things, some personal, some artistic, so it's not just a commit digest, but a little bit more.

But I'm wondering how to syndicate it -- Planet KDE is meant for personal blogs, and this isn't personal. I'm not sure about the other planets my blog is syndicated. And I've had complaints that having a pointer to the new issue on my blog is a bit spammy, and I think I agree with that. So I'm intentionally not linking to Krita.org this time :-) (But it's a good read!)

Does anybody have any bright ideas?

Update: I just learned that if I can teach krita.org to put the Last Week in Krita articles in an rss feed that's unique for what I post, i.e, personal, but from krita.org, I'm fine. I bet our webmaster can figure out how to do that, right Kubuntiac :-)

I've just published the next installment of Last Week in Krita. Lots of cool and fun stuff has happened! We are slowly getting the 2.2 feature plan implemented.

An application isn't complete without good documentation. Those fine folks at Linux Format docked a lot of points from Gimp when they reviewed their new release because the manual wasn't updated yet... Krita 1.6 had a pretty fine manual for a free software application, but given that Krita 2.2 is going to be so much better than 1.6, the manual should be ace, too. And almost nothing from the 1.6 manual is still usable, there have been so many changes.

We have to rewrite, and make it even better this time. There is no way I can do this on my and code, it's got to be a collaborative effort. And there should be video tutorials, as well, as part of the manual. So... Enter userbase.kde.org. It's the perfect central place for efforts of this kind. I've started an outline for a new Krita manual, a manual with more than just a description of every menu option and dialog, but one that focusses on concepts, getting things done.

Also: the first Last Week in krita of 2010 is out!

So today I booked two bed&breakfasts to handle the overflow of Krita hackers for the coming Krita sprint last weekend of February. We'll be seven, maybe eight developers and Peter Sikking. A weekend like this is usually more discussion, getting together and building a shared vision than hacking, but Cyrille, Sven and Lukas will stay on following the actual sprint for a whole week of what I suspect will be very intensive hacking.

Of course, an occasion like this should be marked by having its own t-shirt. The last dedicated Krita sprint was in 2005, and back then we had t-shirts designed by Nuno:

I gave the last surviving shirt to Cyrille during the Oslo KOffice sprint.

So... Is there anyone who wants to set the vestimentary tone for the 2010 sprint?

I missed the last two edition of Last Week in Krita, but my 2009 retrospective is up on krita.org. Summary: it's been a great year, and 2010 promises to be even better! But better read the whole thing...

Thanks to our latest donor, Silvio Grosso, we're at four thousand euros now on Pledgie: Help raise Krita to the next level -- which together with the donations people have made into my bank account directly, means that, even after Paypal has taken its cut, Lukas will be able to work on Krita for another month in the summer!

Here's a screenshot of Krita showing off a feature Silvio asked for that we never really highlighted before: using flake shapes, it's easy to add vector arrows to screenshots, to point out important items. In this case, the default color setting for a new image, which is what I'm working on currently:

Deep-felt thanks go to the more than 160 people who cared enough about Krita that they made this donation drive such an unbelievable success! It is a big vote of confidence and I am determined that we'll prove ourselves worth of it.

The Krita fund raising campaign went live on Monday. Tuesday night, Jos Poortvliet published his interview with me and Lukáš. Today it's Thursday night, and not only have we very nearly reached the campaign goals, we're now at €2,343.00, but I've also bursted out of my Paypal account! So from now on, new donations will go to Cyrille Berger's paypal account, until I've unblocked mine. Our ace webmaster, Kubuntiac has been telling me he warned me this had happened to others, but I simply hadn't expected so many people -- 89 already -- to care enough about Krita that they wanted to help us!

A great, big thank you! to you all!

I can only say that I'm totally floored and apart from the paypal issue, and, deo volente, it's now certain that Lukáš will be able to start doing what you all have decided is so very much worth doing: Make Krita fast!

As I promised, we're having weekly updates on what has happened in Krita on Krita.org, and last week's update has just been published: Week 48: Relative Quiet.

But don't let the title scare you from clicking on the link! It was still a way cool week for us! Quiet for Krita still means lots of development.

After two years and various attempts, Krita finally has a website of its own. And a really nice one, too. Thanks to Krita forum user Kubuntiac who did all the hard work and heavy lifting! Take a sneak peek at krita2d.org -- soon we'll point krita.org to the new location!

It's well integrated within the wider world of KDE websites: we have our forums at forums.kde.org, our tutorials go to userbase, developer information will go to techbase and the developer wiki. We've got a nice showcase with the most impressive images from the forum gallery. Also, the historical screenshots are back, rescued from the old koffice.org website.

I promise -- faithfully! -- that I'll try to make it a tradition to write a weekly "Last Week in Krita" entry for the frontpage. It always surprises me how much we get done in a week. More than seventy commits by seven people is not to be sneezed at! For now, there's some nice and uplifting content for you to read!

And... Watch krita.org for something really exciting later this week!