Pavol Rusnak #cypherpunk #hacker #openhw #privacy #bitcoin #newmediaart

Prezi Offline in Linux

For creating my GameStore talk at LinuxWochen Wien I decided to use new and hip tool called Prezi. I’m not going to write about its features, you have to try and see for yourself. :-) What I can say is that I really like the tool, but it has one big disadvantage - it’s written in Flash.

During the event we had a wireless connection available, but it was rather unreliable, so it was no option for me to present the talk online. I started to investigate the offline options. Either you can download the full blown Prezi Desktop, which is available if you subscribe the service, or you just download the Prezi “Player”. But wait, the page claims it is compatible only with Windows and Mac OS X. Let’s see. I downloaded the ZIP archive and indeed - it contains data folder with your presentation, Windows application (prezi.exe) and Mac OS X application (prezi.app).

Let’s get hacking! Mac OS X application is in fact just a directory structure. I copied the file prezi.app/Contents/Resources/movie.swf to the same location as my data directory and tried to run flashplayer movie.swf. Wow! The presentation started to load, but unfortunately it stopped after few seconds and I ended with this:

prezi1

I tried straceing the process, but found nothing unusual (like failed open calls). Then I downloaded the debug version of Flash Player, run the command again and got this exception:

An ActionScript error has occurred:
Error #2044: Unhandled SecurityErrorEvent:. text=Error #2140: Security sandbox violation:
file:///.../movie.swf/[[DYNAMIC]]/1 cannot load file:///.../data/fonts/LiberationSerif-Regular.swf.
Local-with-filesystem and local-with-networking SWF files cannot load each other.

Aha! Locally stored SWF files cannot load other SWF files, neither local ones, nor remote ones. That’s the problem. Ok, let’s change the standalone player settings. But how?! I tried various command line switch with no success. After couple minutes of searching I found that standalone Flash Player settings could be changed via Flash plugin that loads Settings manager from the Internet? WTF?! :-)

I will make it easier for you: let’s google for “flash global security settings content creators”. The first result at the time of writing this article was this one. Go to this URL, wait until the Settings manager is loaded and then click on the “Edit locations …” button.

prezi2

After that select “Add directory” and choose local directory where you store your presentations. From now on you enabled standalone Flash player to run your Prezis. Congratulations!

Even though I like Prezi, I would be ecstatic if they dropped Flash and used SVG instead as its presentation and interchange format, probably using the uber-cool SVG-edit as the core. :-) It would also enable iPad users to use the tool. And yes, I know about JessyInk, but that’s not exactly what I have on mind …

xkcd 715

I was playing with the idea to write an application inspired by xkcd comics 715 since it was released, but today I finally found time to whip it up! The whole source code is a single webpage (HTML+Javascript/jQuery) around 100 lines long. It basically forms the query by replacing hash sign “#” with the particular number from loop and then asks Google via its Search API. Resulting data are shown via Google Visualization API. It doesn’t have much eye-candy yet, but it works and that’s what counts. :-) I put the presets Randall came up with and also added some of my own. I will now describe the first three in detail:

The first one was "xkcd #", which easily showed that the most popular issues were: 10, 12, 244, 385, 427, 449, 452, 505, 701, 705 and 714.

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I continued with "# czechoslovakia", which of course spotted the most important years of the 20th century for this country (1918, 1938, 1945, 1948, 1968, 1989 and 1993).

img

The last one, "favorite number is #", shows the distribution of favorite numbers. Three, seven, eight and thirteen were expected, but I was surprised to see peak also at 42. I guess you know why. :-)

img

Bear in mind that there are still some outstanding issues and also if you have any ideas for interesting presets to add, I’d be more than happy to include them!

Ah, I almost forgot the link, so here it is: http://gk2.sk/cargo/xkcd715/. Enjoy!

zypper - dependency graph

Yesterday, we needed with darix to obtain a dependency graph of the package you are about to install. I knew that something similar was planned in zypper, so I went to Jano Kupec to check the status of it. Unfortunately, I learned that this feature is not implemented yet. I think it should not be very hard to enhance the zypper package list with some eye-candy, but I haven’t looked into it yet. I would love to have these outputs similar to Gentoo ones (colors and simple ASCII art dependency trees). Btw, zypper already has color support, so if you want to start hacking, there is source code in gitorious.

zypper-flightgear

emerge-flightgear

Jano also showed me a neat trick how to obtain the results we wanted anyway. If you are in similar situation, just follow these steps (they are of course not suitable for everyday use, but still better than nothing):

  1. install package libzypp-testsuite-tools
  2. run zypper install --debug-solver pkg
  3. cd into /var/log/zypper.solverTestCase
  4. open solver-test.xml in your favorite editor
  5. add <graphic/> tag just above the </trial> closing tag
  6. run /usr/lib/zypp/testsuite/bin/deptestomatic.multi solver-test.xml (as normal user, you won’t get any graph when running as root)
  7. you can pan the graph, rotate it with the right click or even save it to disk!

The resulting image can be seen here:

solvertree-flightgear

openSUSE Xfce Live CDs

xfce_cd

Yesterday Andrea aka anubisg1 announced the Live CDs for LXDE, which he built in Build Service with the help of Dmitry Serpokryl. It was a very easy task for me to replace LXDE packages with Xfce ones in kiwi definition, so I can present you the Xfce Live CDs!

I’ve created an entry in our Derivates page and you can download the images from this location. The default user is linux with no password, user root uses the same empty password.

I’ve tested the 32-bit image in VirtualBox and hit some issues (see below), the 64-bit image is untested at the moment. There’s where I would like you to ask for testing both images. Some points first:

  • currently the Qt YaST is used (I had some issues with GTK one)
  • after the login a warning message is shown (about putting “linux” into /etc/hosts)
  • you can install the system to hard drive using the Live Installer icon on the desktop
    • unfortunately this blocks us from enabling autologin (installed system expects “linux” user which is present only on Live CD and login ends in loop, the bug in YaST is being worked on)
    • also some message dialogs about locked storage subsystem are shown during the installation steps

If you hit a new issue, please report it to me. Also if you know how to fix any existing ones, please don’t hesitate as well! Thank you!

Geeko Tram

Almost exactly 3 months ago I blogged about a Geeko Bus. What a surprise I had today when I saw a tram decorated in a very similar fashion. The weird thing is, that both bus 183 and tram 8 have their stops near our Prague offices. There is definitely something fishy going on! :-D

tram9039

I was even able to find a video on Youtube, so you know it is not shopped. :-)