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Archive for August 28th, 2008

Hackweek: Drawing the Lower Case Characters

August 28th, 2008 by

In my previous post, I talked about the majuscles. Now it’s time to implement the minuscles, or the lower case characters.

This time, I omitted the sketch and try to implement it directly in FontForge. I think, it worked pretty well, but judge it yourself:

First draft of the lower case characters

It’s a first draft. Of course, I have to adjust a lot of things. The font is far from finished or being perfect. 🙂

After this, I have to find a good name. Any suggestions? Robert thinks, Toms Mono is a funny name and I should keep it. 😉

Button Order in YaST: Trying to Make Peace with Both Worlds

August 28th, 2008 by

KDE and GNOME have different button orders. Like many desktop-related issues, this has been a subject of heated debates time and time again.

Where KDE uses something like this:

GNOME would use something like this:

Which one is right? Which one is wrong? There is no real answer to that; it will always be more a religious debate rather than an objective discussion.

YaST Button Order

So, which button order to choose for YaST?

For historical reasons, we used the KDE button order. But this has repeatedly started the same heated discussions as for KDE vs. GNOME, with the same results — which is, no tangible result, only something along the lines of “because we says so” (and didn’t you always hate it as a kid when mom or dad said that?).

YaST should not favour one of the major desktops over another. YaST should work well for all users. So, YaST should adapt to the environment it runs in.

YaST comes in different flavours. There is the graphical version: The YaST Qt UI (user interface) engine (Side note: The YaST Qt UI is not in any way KDE specific; Qt just happens to be a great toolkit for making graphical user interfaces, and KDE happens to use it, too. There is not one single line of KDE-specific code in the YaST Qt UI.).

There is also the text-based version, the YaST NCurses UI.

As an alternative graphical UI, there is also the YaST Gtk UI which uses the same widget toolkit (Gtk) as GNOME. That brings YaST closer to the GNOME crowd. At least, that’s the theory. Yet, that alone didn’t improve the situation in any way for this button order issue:

YaST dialogs are specified in a subset of the YaST-specific YCP scripting language. Those dialog descriptions include input fields, list boxes, headings, etc. as well as the logical arrangement of all those user interface elements (widgets, even though that term has seen a lot of misuse recently). And buttons, too, of course.

So, the arrangement of buttons was still fixed. The YaST Gtk UI couldn’t really do anything about changing that button order so it looked more GNOMEish.

This is now different. We introduced a new widget ButtonBox that abstracts exactly that. A YaST module developer now only specifies “there is a ButtonBox, this is where I put my buttons, and the ButtonBox will arrange them as appropriate”.

…for users…

So now it is possible for the first time to use the proper button order for each environment: GNOME button order for the Gtk UI, KDE button order for the Qt UI.

But there is more.

…for power users…

The Qt UI can now demonstrate the fact that it’s not KDE specific. It checks what environment it runs in and uses the appropriate button order: GNOME button order when running in GNOME and KDE button order for KDE (or other window managers).

It checks the $DESKTOP_SESSION and $WINDOWMANAGER environment variables to figure that out. But of course power users can still override that and set the $Y2_BUTTON_ORDER environment variable to “KDE” or “GNOME”.

…for YaST developers…

Of course, such a change doesn’t come over night. There is a very large amount of YaST code. I counted 69 .desktop files in my /usr/share/applications/YaST2 directory; that corresponds to 69 YaST modules. On my machine I have 432000+ lines of YCP code below /usr/share/YaST2 . Now try to figure out how many YaST dialogs that might be, and how many of them need to be converted to use that new ButtonBox mechanism.

Obviously, it’s a lot of stuff to change. So the change should not hurt the people doing the change more than it absolutely has to. Don’t forget, it’s not just working hours that have to be paid; it’s also working hours that can’t be spent on implementing other features or on fixing bugs. And any change (even more so changing code at so many places) means a possibility to introduce new bugs.

…trying to be smart…

So this ButtonBox mechanism was made to be smart, to re-use existing information (things that are already there in the code), to make good use of existing conventions.

In principle, using something like the ButtonBox means having to tell it which logical role each button has so it can be arranged according to the current button order’s conventions: Which button is the positive confirmation of a dialog (it might be “OK” or “Continue” or “Yes”, but it might also be someting like “Save” or “Print”), which one is the “safe escape” (“Cancel”, but sometimes also “No”), which one is the “Apply” button or the “Help” button, and which ones are just “other” buttons. Remember, YaST is being translated into some dozen languages, so just hard-coding the English button labels won’t do.

But we already have a mechanism that maps (translated!) button labels to function keys, and that mechanism does something similar: There is a list of commonly used button labels and what function key is to be used (in the NCurses UI) for them. For example, “OK”, “Continue”, “Yes”, “Next” all map to the F10 key, “Cancel” to F9, “Help” to F1.

Extending that thought some more, it makes sense to assume an “okButton” role for buttons that are otherwise assigned the F10 key, “cancelButton” for buttons that get the F9 key, etc.

Buttons in YCP each are assigned a widget ID. That ID is the “handle” by which a button is being referenced; this is what the YCP application receives when it is informed that the user clicked that key. When specifiying a layout with buttons, this looks (slightly simplified) like this:

         `InputField(`id(`name  ), "Name" ),
         `InputField(`id(`street), "Street" ),
               `PushButton(`id(`ok    ), "OK" ),
               `PushButton(`id(`apply ), "Apply" ),
               `PushButton(`id(`cancel), "Cancel" )

As shown in this example, a button with the “OK” role typically has an ID like `id(`ok), a “Cancel” button has `id(`cancel), an “Apply” button has `id(`apply). So this information is used, too, to figure out what role a button has.

Of course, there are still situations where the system needs to be explicitly told what button has which role: It’s hard to figure out in a generic way that a “Print” button or a “Save” button has the “okButton” role in a dialog. In that case, the YCP developer has to change the code to look like this:

`PushButton(`id(`print), `opt(`okButton), "Print" )

…the normal case…

But in many cases, the migration is as simple as replacing the `HBox() (the horizontal layout box) holding the buttons with `ButtonBox():

         `InputField(`id(`name  ), "Name" ),
         `InputField(`id(`street), "Street" ),
         `ButtonBox(        // This is the only line that changed
               `PushButton(`id(`ok    ), "OK" ),
               `PushButton(`id(`apply ), "Apply" ),
               `PushButton(`id(`cancel), "Cancel" )

…taming the masses…

Just imagine doing only this little change in 432000+ lines of code – of course, only where such a `HBox() contains `PushButtons, not just blindly replacing all `HBoxes. And just changing it is not all there is to it; each dialog has to be tested, too. And that alone is not so trivial: A dialog might easily only be shown in very exotic cases, so the developers doing the test have to recreate each of those exotic cases just to see the dialog.

You see, masses of code are a dimension of complexity all of their own. Little things that look trivial to do gain a whole new meaning. Everybody can do this change in one or two places, but try to do it in someting as big as YaST — without introducing new bugs that would wreck other people’s system.

Yet, we do those kinds of changes, typically unnoticed by the user community. And those little things are what, if added up, make or break a system’s quality.

We don’t take such decisions lightly. But we felt that in this specific case (the button order) the gain would be worth the pain: Users should feel at home in the tools we provide. And having the buttons where you are used to is part of this feeling at home.

Further Reading


HackWeek III Day 3 – Diary Of An Outsider

August 28th, 2008 by

Day 3 started off relatively early in comparison to day 2, why? Because I was continuing my ChatWeek with a fairly important chat with a fairly influential person.  The person in question was non other than Jeff Jaffe, Novell’s CTO.  Fellow Community member Pascal Blesser and myself were invited to have a relaxed discussion with Jeff about openSUSE and Novell and bring up any issues/comments/etc that we may know of.  We spoke with Andreas Jaeger and Michael Loeffler yesterday about the impending meeting, and discussed at some length some of the items not just because we hoped to bring them up with Jeff, but because we felt they warranted discussion regardless of who it was in front of.

The meeting with Jeff went well, and we appreciate the opportunity immensely to be able to speak fairly frankly to Jeff (no, neither of us swore or threw any furniture in the style of a Rock Star).  We didn’t manage to go through all the points we would have liked, but we certainly got through the big burning issues that we had.  After almost 90 minutes Jeff had to leave and do the rounds to see how HackWeek was progressing from the “shop floor”.  This meeting wasn’t a marketing blah blah meeting but a definite participation on all sides; there were times when disagreement happened but as the atmosphere was relaxed it was pretty easy to move on.

Afterwards I tried (relatively unsuccessfully) to get on with my project and edit the footage from the previous day.  Why oh why is video editing not simple?  Either applications are just way way way too difficult or just unbelievably unstable to the point of uselessness.  Hopefully tomorrow will be more successful when I pressgang Thomas Schmidt into helping me 🙂

For ALL participants of HackWeek: SudoWrestling, a great Linux focused podcast and blogcast (sometimes they can’t be bothered to talk, strange considering they’re women 😉 ) would really like to hear from you about your projects.  Now is the time to blow your own trumpet and chat to these two lovely Linux loving lunatics.

HackWeek III Day 2 – Diary Of An Outsider

August 28th, 2008 by

So the fun and sun in Nurenberg continues 😀

Again day 2 started off very much as day 1 – lots of discussions.  This is not a bad thing, and maybe Novell would consider sponsoring a ChatWeek (it could be condensed into 2 or 3 days), it is a fact that communication is the one major stumbling block that any company/community suffers from and Novell and openSUSE are no exception to this.

We started with general discussions and continuing some of the discussions we had over dinner last night.  After lunch we then continued our discussions on openSUSE and what/how things could be improved – highly productive and very inspiring to get internal and external community members to speak honestly and bluntly about their thoughts and ideas. 

Note to the community (yes, all of you!): If you have thoughts on what or how to help imporve anything within the openSUSE universe speak up!!  If you’re not sure who or how to do so, the key contact details (in no particular order) are Zonker, opensuse-project mailing list, #opensuse-project irc channel and of course the openSUSE Board.  One of the advantages of openSUSE is that you can pick things up and run with them, if you need any help just ask and people will rally around (sometimes it takes a bit of time but it does happen, honest).

After all the discussions I had just enough time to grab a drink before the first openSUSE Marketing Team irc meeting took place.  This was shorter than I would personally have like, but that was down to one very important reason – the HackWeek BBQ!

The BBQ was and is a great opportunity for people just to chat on all levels, and general have fun with some fine food and some fine Bavarian Beer – Pascal will certainly disagree with me on the last point, but then again he is kind of correct; being Belgian he is used to a much wider variety and quality of beers, just go to FOSDEM to find out 😉  You can see a montage of the video that I took over here – yes I know it’s evil flash!

The party atmosphere went on long into the night and everyone managed to enjoy themselves. Thank you SUSE for the fine food and beer, and thank you Pascal for bringing some prized Belgian beers for comparison with the Bavarian ones.

Hackweek Days 2 and 3

August 28th, 2008 by

Jan-Simon and Stephan On tuesday a couple of developers met to discuss cross-platform building in the openSUSE build service.

In the evening we had a BBQ and there Jan-Simon and Stephan discussed the openSUSE weekly news that Jan-Simon then wrote on wednesday – this time from Nürnberg.

Pascal left on wednesday and told me that he really enjoyed “Chatweek”.  He – and others including myself – used the chance to meet each other for many discussions.

I took part on wednesday afternoon in a rather long discussion on the different security defaults of server and desktop products, e.g. how to setup a laptop so that it allows a logged in user to install patches and a server that only the admin can install patches – and do this right out of the box.

Hackweek Visitor

August 28th, 2008 by

Yesterday afternoon, Hackweek III was running on full throttle, suddenly Jeff Jaffe, the CTO of Novell, stepped into our office. No meeting appointment, no big words, just a “What are you guys working on in Hackweek?”. Well, everybody who ever was working as an employee might understand that having the boss of the boss of the boss stepping into the office spontanously can be a bit exiting, but that is just the first two seconds. I think it is cool if executives do that.

In the company I worked before S.u.S.E. the owner always visited us on friday afternoons and sat on the developers desk. He was somehow geeky and was simply interested in tech talk. That made me nervous in the beginning, but later it was fun and informing. It was a great opportunity to present good ideas or concerns and on the other hand he gave a lot of first hand information what customers say, how the fairs went etc. In this kind of situation we convinced him finally that our under-cover Linux port of our solaris based product was way better for all customers than the Windows version most customers (and thus the executives) asked for.

I was hacking on my KDE application Kraft when Jeff asked, which is certainly not for the enterprise market. But given that applications are the key to pull people to linux we agreed that it is a cool Hackweek project 😉 I forgot to ask him what he is hacking on 🙂