Bitwise Evolution

Ubuntu 8.10 configured most everything properly, as mentioned in the previous post in this series, but it did not result in a functional pen.

The tablet screen is a wacom digitizer with a pen that has two buttons (eraser and a finger button), and the tablet can differentiate between touching and hovering. The linux wacom driver & tools are necessary to get this all working. While I didn’t find a single page with instructions that worked flawlessly, I was able to figure it out from a collection of links:

• The Linux Wacom project:
  • http://linuxwacom.sourceforge.net/index.php/minihowto
  • http://linuxwacom.sourceforge.net/index.php/howto/x11
• The Aliencam blog:
  • http://blog.aliencam.net/articles/aliencams-customized-ubuntu-setup-guide/

First off, you will need the latest version of the linux Wacom driver (8.2.1 at the time of this writing). The driver versions seem to be tied to your kernel versions, so this is quite important. The wacom-tools package that comes with Ubuntu is not sufficient (in fact, you’ll want to uninstall it if you have it already).

Once you have the wacom package downloaded, follow the directions for installing it in the howto (linked above). The wacom package uses a typical configure, make, make install process but there are a few kinks:

• configure (almost?) always succeeds, regardless of the dependencies you have yet to fill. The make step will simply not build all the things you need if this happens, but it won’t fail visibly.
• You’ll need to copy the kernel module into the /lib/modules/uname -r/kernel/drivers/usb/input/ directory manually (creating subdirs if necessary), before running make install. (This is outlined in the mini-howto.)

Once wacom is installed, you can begin working with the X.org configuration. This is fairly clearly explained at the aliencam blog linked above, or you can use my xorg.conf here.

After doing that, you should be able to reboot and the pen should be working. You can do things like configure the buttons with xsetwacom (and you’ll need that when it comes time to rotate the screen), but I kept getting this error when I tried to run xsetwacom:

I made a lucky guess, and fixed the problem with a quick ldconfig:

Update: There were some issues with the wacom calibration after a sleep/resume cycle if the laptop screen had been rotated during that prior wake cycle (this happens a lot more than it seems, given how complex that description is.) I’ve written up a workaround here.

I finally broke down and bought a Lenovo X61 tablet (with SXGA+ screen!), and it arrived this week. This is the first of a series of posts about getting it up and running with Linux.

First off, some specs:

• Lenovo X61 Tablet PC with XSGA+ (1400×1050) screen (not multi-touch)
• 4 gigs of ram
• 200gb SATA hard disk
• WIFI (Intel PRO/Wireless 4965 AG or AGN)
• Gigabit Ethernet (Intel 82566MM)
• Bluetooth
• Wide-area networking card (3G)
• Fingerprint reader
• Integrated SD card reader (Richoh R5C822 SD/SDIO/MMC/MS/MSPro)
• Intel Audio (82801H ICH8 Family audio controller)
• 1 PCMCIA (type-I?) slot
• 4-cell battery
• Ultrabay Slim (which will be holding my Ultrabay CD-RW / DVD drive from my old T42p)
• Intel Mobile GM965/GL960 video controller. (256mb video ram?)

I’ll flesh that list out more as I can find the details (eg: wireless chipset, video, etc..)

First off, I blew some time poking around in Vista of course :). The handwriting input app is phenomenal in a lot of ways. It works very well, training is well integrated, and it has worked with every input area I’ve tried. It could be better if it had contextual clues, and could tie into things like Eclipse’s intellisense. Overall, though, it is amazing how simple it is to use, and how aesthetically pleasing the handwriting actually is. There is a lot to be said for using a couple extra pixels to make the strokes taper off as you pull the pen away. It has QWAN.

That done, I started to move on to installing Linux. I’m giving Ubuntu 8.10 the first chance, and I thought I’d try using a USB-based install so I wouldn’t have to monkey around with the Ultrabase & drive. If you have an 8.10 system already, you can easily create a bootable usb ubuntu drive with usb-creator and an ubuntu iso. This takes perhaps 45min – 1 hour.

Booting was as simple as going into the ibm bios-like page (by hitting the ThinkVantage button on boot) and telling it to boot from another device, then selecting the usb drive (that I had already inserted). I split the existing 200gb partition in two with the ubuntu installer, keeping Vista in it’s 100 gig sandbox, and leaving the remaining ~100 gigs for Ubuntu to partition further (which it did, as two partitions: one for / and one for swap. /dev/sda5 and /dev/sda6).

I do wish it had said how much space was being allocated to each of those partitions though. The installer didn’t give any indication.

Installation from booting the installer from usb to booting into the installed system took right about 30min. I’m impressed :)

Out of the box:

• The screen is the proper res
• Wireless looks like it might be working (I have to AP to verify)
• Sound works
• the pen does not
• Screen rotation does not work
• closing the lid shuts off the screen, but does not put the laptop to sleep.
  • This was easily fixed in the gnome power-management settings, and hey, it resumes too!
• putting the laptop in tablet mode seems to have no effect (at least it doesn’t shut off the screen ;)
• Some power management is clearly working (screen dims when unplugged)
• bluetooth was detected, but I have to way to test it.
• Dual-booting seems to work just fine, although there are two entries for Vista in the grub menu, and the first boots into the Rescue and Recovery system. Vista also had to do a chkdsk, and reboot before it would load.

More information as I figure it out :)

I desperately needed to find out why the tutorials I’ve been following for an Eclipse PDE task today kept referencing a startup.jar file that I could not locate.

A couple google searches later turned up this link:

http://dev.eclipse.org/newslists/news.eclipse.platform/msg62159.html

The poster in that thread had the same problem (back in Feb. 2007), and found the answer, but none of the content in that thread makes it trivial to locate the answer again.

The responder (with the answer) simply included a link to another mailing list:

http://dev.eclipse.org/mhonarc/lists/cross-project-issues-dev/maillist.html

Notice that that page is not constant. Today, it shows the most recent posts as of October 31st, 2008. In order to figure out what had happened to startup.jar, I had to take into account the OP’s response (”Ok so this is very recent.”), the timestamp on the messages (Mon, 12 Feb 2007) and then navigate the mailing list archives to find that time period, and start reading.

Please don’t put people through this sort of crap. It’s generally not difficult to find permlinks to a given email, or include a quick note with the actual answer. I have the answer now (startup.jar was replaced with org.eclipse.equinox.launcher in 3.3), but there is no way that I can tie that answer to the conversation I’ve linked to above.

For the purposes of Google:

If you’re having this problem:

I’m trying to do some automation, but I’m running into a problem with the 3.3 integration build.

java -cp plugins\org.eclipse.platform_3.2.100.v20070126\startup.jar org.eclipse.core.launcher.Main

doesn’t do anything. It doesn’t say anything. The only information I’m getting is an exit status of 13.

Then you need to use “java -jar plugins/org.eclipse.equinox.launcher_1.0.0.v20070207.jar” (adjusting the version numbers for your installation).

(Edit: If you’re reading this after OSGi R4.2, then there is almost certainly a better way to accomplish the same thing)

I’ve been digging into OSGi a bit over the last week or so inorder to create some Eclipse plugins that will automatically discover eachother, and I’ve been generally impressed with the framework on the whole. The documentation is a bit lacking, but there are some good blog posts about it. (Specifically [Neil Bartlett's introduction to OSGi][intro].)

One thing that bugged me is the repetition needed when you implement the CommandProvider interface to add commands to the OSGi console. CommandProvider defines one method you must supply:

OSGi then uses reflection to extract each of the methods that starts with an ““, and supplies those methods to the command environment as new commands. (The “” is trimmed, and the name of the method becomes the command name.) General practice is to include the name of the method in the return value of getHelp(), along with a description of what the method does, eg:

This seems like a pain to maintain, so I took a quick look at annotations, and propose a new syntax:

Here we’ve extracted the getHelp() method into a new superclass, so our SampleCommandProvider now extends an abstract class instead of implementing an interface. It also makes use of an Annotation, which we need to define:

Finally, we just need to define the superclass that implements getHelp():

Note that the actual reflection on the class only happens once — all subsequent calls to getHelp() use a cached copy of the documentation.

[intro]: http://neilbartlett.name/blog/osgi-articles/

The venerable Joel Spolsky asked recently why someone hasn’t made a device that clips to the back of a desk and:

* It’s a power strip
* It’s a network hub
* It’s a USB hub
* You clamp it onto the back of any desk

The idea being that:

This would make it easy to plug in laptops, USB peripherals, and all your rechargers at your desk without crawling around on the floor.

He links to a device that does some of this, and runs ~$150/device. At that price, I think a better solution is a docking station–when you get down to it, I don’t want to plug in 4 things every time I sit down even if it doesn’t involve crawling under the desk (power, video, usb, ethernet and possibly audio). I think it’s unlikely that all the features needed above are really necessary when you just show up for a meeting, or hop over to your coworker’s office for a short hacking session. Many conference rooms these days already have tables wired for ethernet / power and svga video to a projector.

Joel Spolsky and Jeff Atwood just launched the public beta of Stackoverflow today, with the intent of building a community for high-quality technical questions and answers. I’ve been using the site for about three weeks now, during the closed beta, and I’ve noticed a disturbing trend that was outlined in Joel’s announcement post today:

Want to know an easy way to earn reputation? Find a question somewhere with several good, but incomplete, answers. Steal all the answers and write one long, complete, detailed answer which is better than the incomplete ones.

The site presents an interface where much of the functionality is hidden from new users. You can’t comment on posts, for example, until you’ve earned 50 “rep”. Voting up takes 15 rep, voting down takes 100 rep, and each downvote you place will cost you one rep. You gain rep by posting questions and answers that other users vote up, or accept. The result is an addictive system that, in theory, prevents “Griefing” (the system does NOT prevent griefing, by the way. It is extremely easy to game.)

Because of this, it is tempting to re-post successful content from other sources, and nothing the creators (Atwood and Spolsky) have incorporated into the site, or the recent announcements, has indicated that this is objectionable. Afterall, good content on Stackoverflow will improve their service, regardless of where it came from, and regardless of whether it is properly credited.

After using stackoverflow for a couple weeks, I think that they have created a useful service, but I also want to call them out for providing an environment that is encouraging plagiarism. Duplication/copying of content within stackoverflow does not set easy with me, but I’m willing to accept that the content I create for stackoverflow is public domain, and is free to be copied at will. However these posts are not.

The ‘proper’ way to do user interface design is hotly contested in the OSS software development world, and the discussions usually boil down to three suggestions:

1. “Just write it — it’s not that hard”
2. “Use [glade|qt designer|netbeans|...] — all the widgets are there”
3. “Just use pencil/pen/whiteboard/etc — it’s faster”

I don’t agree with any of these — (1) is completely unreasonable. Some people may be able to hack out a UI in their favorite language quickly, but when you suddenly need to move half the UI into a new dialog, or out of a dialog and into the main window, and change the tabs into a check list, with sample data, you’re screwed. Once you finish manhandling your code to account for that change, you’ll need to add a component that is shaped like a septahedron with 7 distinct clickable areas and a tooltip that includes the latest stock quotes, and that tooltip needs to be scrollable. The widget set places unreasonable restrictions on the design phase of your project.

Option (2) suffers from the same issues as (1) — you’re constrained by the widgets available, although this is less of an issue because it’s generally easier to add images, and the images can look like the widgets you’re missing. However, since GUI UI development tools are, well, for development, they require you to do lots of irrelevant (at this stage) tasks, like specifying how objects will behave when they’re resized, and dealing with layout managers.

(3) is the closest fit for my needs, and I do do lots of paper/whiteboard prototyping, but eventually, I need to show something that looks real, and sketches don’t cut it. There simply isn’t enough resolution there to convey everything that needs to be included in the mock-ups I create.

Hm.. perhaps I should go into what I do need, since my needs may be pretty esoteric. If you’ve made it this far, you’re probably seething with anger, or you’ve got some idea of where I’m coming from. I’m frequently in need of electronic versions of UI prototypes for remote collaboration, “wizard of oz” testing, or for inclusion in presentations and reports. These mock-ups need to look “real” or the is a substantial risk of biasing any experiments, and there is an expectation of polish that can’t be reached with hand-drawn interfaces. Since a lot of what I create is to solve novel problems in (at times) esoteric domains, we often need to use a mix of existing and novel widgets.

Generally, we use Visio to create these interfaces. It offers a good balance between vector drawing capabilities and shape templates for common UI widgets / forms / etc. You are also able to import images, which is fairly critical when updating or adding to the UI of an existing tool. (It’s easy to take a screenshot, clear out the details with the Gimp, and import as a background layer in Visio.)

Unfortunately, I’ve been unable to find any OSS tools that can fill this niche as well as visio. There are a few, as recent posts from slashdot and the old Joel on Software forums show:

• DENIM: Lets you sketch out interfaces with a tablet / mouse and create navigable web sites from those sketches. Lacks in the “polish” area.
• Pencil: Firefox Plugin. Peformance has been poor, in my experience. There are very few widgets (currently) available, and no image import capabilities (this is a huge flaw, IMHO). Pencil could turn into something great, though.
• DIA: Last release was in March, 2007, but the svn repo does show some activity. DIA lets you create things like network diagrams, UML, and flow charts, much like Visio, however, there are no UI stencils. Instructions for creating new stencils (’shapes’) exist, but the svg support for shapes is very limited (no gradients, no rounded rectangles, etc..) and the documentation is even worse.
• Kivio: Much like dia, with essentially the same failings.
• QT Designer | Glade | etc.: see above comments about GUI development tools.
• Inkscape: Nominally a vector drawing tool, much like Adobe Illustrator, Inkscape has an active community, good documentation, and it is quite stable. Unfortunately, it is not possible to customize the pallets / shapes available, and there is not much community support to make it a good UI design tool (aside from what can be done with any vector drawing app of this quality).
• Yahoo! UI Stencils (YUI): Not really a tool, but rather a collection of svg images of common interface widgets.

None of these, on their own, do the job. However, with nothing else looking bright, I’ve been digging into Inkscape more over the last few days, and I think I’ve figured out a workflow that will do.

First off, the YUI stencils are critical — but they are not in a format that can be easily imported and used as “widgets”. Ideally, Inkscape would let me define custom shapes, complete with constraints on the sub-components of those shapes to influence resize and translation behaviors, but that isn’t yet available (to my knowledge). You can get around this, somewhat, by using the open dialog as a pallet of sorts:

“If you have a number of small SVG files whose contents you often reuse in other documents, you can conveniently use the Open dialog as a palette. Add the directory with your SVG sources into the bookmarks list so you can open it quickly. Then browse that directory looking at the previews. Once you found the file you need, simply drag it to the canvas and it will be imported into your current document.” (From the *Tips and Tricks* tutorial in Inkscape)

This would work reasonably well, if the open dialog were not modal! (Ranting about modal dialog is another post, or two, at least.) Thankfully, you can drag from the dialog into an inkscape instance even if they are running on different processes :). Therefore, you can start up two inkscape processes (NOT via the “new document” option on the toolbar or file menu — you have to actually start up two instances separately or the dialog’s modality will still interfere with your work). Once you have the processes going, and two inkscape windows, open the open dialog on one of them, go to the directory with your widgets, minimize the (now useless) inkscape window you opened the dialog from, and rock on with the YUI stencils & whatever other tools you need to hack out your UI in the other inkscape instance.

There are a couple of things to keep in mind:

• Inkscape supports layers, so you can create stub data in a separate layer from the UI structure, and set the background content in another layer, etc.. so you don’t have to worry (as much) about grabbing the wrong thing and moving it out of place.

• The drag-and-drop action from the open dialog will include everything in the dragged svg file — so the YUI stencils (or any custom shapes you make) need to be broken out into separate files. (I’ve done this for some of the components, and you can download those files here: (Broken out YUI stencils). They are released under a Creative Commons Attribution 2.5 License.

  Pencil (or one of the other options) may work better for you — many people have complained that their clients think an app is nearly finished because the UI looks “real”, and there are numerous ways to address that. (eg: NapkinLAF for Swing apps.) I haven’t had this problem, and something like NapkinLAF doesn’t address the problems I have, which are all related to pre-coding UI design.

With the launch of the StackOverflow beta I posed a question about python static analysis tools, as I have been playing with python and django recently for some side projects. The responses at Stack Overflow quickly pointed to PyChecker, PyFlakes and PyLint.

Over all, it was a disappointing experience. My experiences are outlined below, and they (more or less) reflect this more extensive review by Doug Hellman.

Here are my first impressions of pyflakes, pychecker and pylint:

• pychecker: It crashes frequently, most of the runs I tried resulted in Errors that originated in the pychecker code (eg: AttributeError or IndexError: list index out of range were the most common). For some reason I had to set the DJANGO_SETTINGS_MODULE environment variable before it would even run on any of the app code, and the documentation is very sparse.

• pyflakes: ‘pyflakes –help’ throws a TypeError — erm… Documentation is also very sparse, and pyflakes is very forgiving (as far as I can tell, it only reports compile errors, warnings, redefinitions, and some concerns about imports–such as unused and wildcards). pyflakes also seems to repeat itself:

  eventlist/views.py:4: ‘Http404′ imported but unused
  eventlist/views.py:4: ‘Http404′ imported but unused
  eventlist/views.py:5: ‘from eventlist.models import *’ used; unable to detect undefined names eventlist/views.py:59: ‘authenticate’ imported but unused
  eventlist/views.py:61: redefinition of unused ‘login’ from line 59
  eventlist/views.py:5: ‘from eventlist.models import *’ used; unable to detect undefined names
  eventlist/views.py:4: ‘Http404′ imported but unused

• pylint: This seems to be the most capable of the tools suggested. It has the best documentation. LogiLab provides a tutorial, pylint has a help screen, and there is a (broken) link to a user manual, which would be extremely helpful. There are some issues with applying pylint to django, since pylint doesn’t know about the django classes (such as models.Model). This means that a fair number of otherwise valuable errors are generated about missing class fields. eg:

  E:105: get_events_by_tag: Class 'Tag' has no 'objects' member
  

  Parsing these out automatically will be very difficult without some additional knowledge of the classes in use. I’m not sure adding that is feasible, but it does seem likely that pylint is capable of dealing with this in the “right” way. (I probably just need to point it to the django source, but there are no command line params that look likely, and, as mentioned earlier, the user manual is inaccessible.)

For the moment, I’m still looking into pylint — pychecker and pyflakes need better documentation and they need to become more robust.

A groggy morning in Seattle started with the typical regional sunshine forcing its presence through heavy cloud cover–the first overcast day in nearly a week of clear, scorching weather.

Seattle to Newark, hustle off the plane, bad coffee, hustle to the next gate, and then encamp for the next 9 hours of travel across the Atlantic. This leg was on a relatively empty 767, but I still can’t really sleep on planes. I have become an overnight advocate for noise-canceling headphones though–they make the difference between muffling a sound and turning it off. I found the Athens airport to be considerably less hyper than most US airports (with the exception of Syracuse, which is not much of a surprise), although I think it is universal that no one is particularly happy when at an airport, and that feeling seems to be contagious. It’s unfortunate that it is so difficult to visit a place without first visiting an airport there.

I few hours later I hopped on a tour bus to take everyone from the recent batch of flights off to our hotels in Patras–a wild 4-5 hour ride along the shoulders of “one of the worst roads in Greece” as some one here put it. The careening along coastal roads was punctuated by hairpin turns in seaside villages with roads small enough to make any driver feel claustrophobic, and we were riding in a bus that would seat 30-40, with luggage. It was much like watching a game of Fifteen Puzzle, with a key twist: every tile (car) was self-aware and initially greedy.

We did eventually make it to the Hotel Tzaki almost exactly 24 hours after leaving Seattle.

There was once a time when your home directory was treated as a nearly sacred place, a safe haven where you had near complete control. This trust was only breached for very special reasons: user specific settings and background storage for applications could go in “dot-files”–the hidden files or directories that begin with a “.” and therefore don’t show up in normal directory listings.

Unfortunately, things began to change. I don’t know what kicked it off, but soon there was a Desktop (or desktop) folder. It was glaring–many XFree86 window managers don’t even have the concept of a desktop, but the defaults environments were (and still are) often set to Desktop Managers. Web browsers took after the DM’s, and soon we all had these glaring “Desktop” directories hanging out whether we wanted them or not. I’ve managed to tolerate this infraction for years, and aside from the occasional frustration (eg: Ecilpse and NetBeans, with their request for a ~/workspace and ~/NetBeansProjects directories).

However, today things changed.

Documents? (Ok, I can sort of understand that one.) Music? Pictures? Templates, PDF, Public, and Videos?! Did I suddenly become a master of multimedia? Keep in mind here, I’m a java hacker on a Linux box–this isn’t exactly a fine-tuned rendering/desktop publishing platform. And of course, every one of those directories is empty. Thankfully, I checked before deleting documents vs. Documents (I’ve been bitten there before–on a mac due to case conflation–but that’s another story).

Why would I want a directory called PDF? I can understand (possibly) wanting to tag files with “PDF”, but as part of a single-dimensional sorting criteria? (Hey, lets store all my .h files in ~/H/ and all my .cpp files in ~/CPP/! It’ll be great!)

Needless to say, I’ve removed the offending directories, and this time I’m ready:

(newlines and comments introduced to improve clarity — if you’re pasting this into a shell, you’ll need to either add \’s or remove newlines.)

KFSMD (kernel-filesystem-monitor-daemon) is an app that does exactly what it’s 32-character name says. Whenever a filesystem change occurs, it knows about it. The -cat part just tells it to print to stdout, and the hunk of perl does some minor processing, and introduces time stamps.

I’m actually running this in a sticky terminal that’s pinned to my E17 desktop, so if/when something starts building an empire in my home directory, I’ll be able to compare with what apps are running, and hopefully track it down. (It would be nice to collect the PIDs of the process that actually issued the system call to touch the file system, but this is good enough for now.)

Now we wait…

(This article got me going with KFSMD.)