Peaceful Holidays ...

... and a Happy 2009 to everyone from me and my family.

Presented by my XO-hugging USB men (who seem to have more memory capacity than me at times).

Featuring a seriously tree-infested Etoys project, with snow (for those living south who cannot enjoy the white fluff this time of the year).

And see you at 25C3 I hope!

Emulating the latest stable OLPC XO software

Even with XO laptops readily available now there are quite a lot of reasons why one would want to emulate it on another machine. One being to hook up a projector. Unfortunately there are quite a number of hoops (*) one has to jump through to make it work.

Anyway, I made a virtual machine that allows me to emulate the XO in VMWare on my Mac, running Sugar in the XO's native 1200x900 resolution, scaled down to a nice physical size in a window on my regular screen (fullscreen works, too). Sound works (even Tam Tam), Browse works (so networking is good), and after setting a working Jabber server I do see other XOs in the neighborhood view (Chat worked fine). Camera and mic are half working (Measure crashes, Record shows blank picture, but reportedly does record video), and a "Sugar restart" does not actually restart Sugar, but apart from that it seems fully functional, and much nicer than the emulations I had used to date.

Click to see actual screenshots (calibrated to match the XO's physical extent using the Ruler activity on my MBP's 110 ppi screen):

And here you can get that virtual machine (665 MB, 2 GB unzipped): VMWare-8.2-767-bf.zip

I made this using VMWare Fusion, which I found to be much better at running Linux clients than Parallels Desktop (I had been using that for 2 years). Give it a try, it's free as in beer for 30 days. No, I don't get paid if you buy it.

Update: Reportedly it does work in VMWare Player on Windows and Linux, too (see comments). And maybe someone can make an appliance for even easier use?

(*) Now to the hoops:

• I started with the 767/ext3 image from http://download.laptop.org/xo-1/os/official/
• extended to 2 GB by appending /dev/zero
  (jffs2 compression gives roughly 2 GB too)
• enlarged the partition to full 2 GB
  (using fdisk and ext2resize)
• mounted that in a Fedora 10 virtual machine
  
• copied over the F10 kernel, initrd, and modules
  (olpc kernel wanted AMD instructions)
• edited grub.conf to use that kernel
  
• and appended a root=/dev/sda1 kernel arg
  (the fedora kernel wants to use LVM otherwise)
• unmounted
  
• created new virtual machine
  (that disk, 1 CPU, 256 MB RAM, NAT networking)
• booted into that new system
  
• installed Perl
  (for vmware tools installer)
• installed vmware tools
  (to get the X driver)
  (but none of the kernel modules, would need make/gcc/etc.)
• deleted Perl
  (to restore the default sw environment)
• copied the existing xorg-vmware.conf to xorg.conf
  (to get 1200x900 resolution w/ 200 dpi)
• booted into Sugar
  (looks really nice so scaled down)
• installed activities
  (took a long time, maybe it's my DSL)
• tested a bit
  
• rm -r ~olpc/.sugar
  (to remove my personal data)
• should have deleted sshd host keys, too, but didn't
  
• shut down
  
• zip
  
• upload
  
• ...
  
• ...
  
• ...
  
• still no profit? ;)

Enjoy.

European grassroots meeting

I went to Brussels last weekend, meeting with folks from OLPC Europe, OLPC Boston, and some other European grassroots (me representing OLPC Germany e.V.). We mostly discussed how to implement the new Give-1-Get-1 program as well as Give-many here in Europe. Some notes are available.

And, while sitting together at a nice Cafe on Sunday I made this little Etoys project to celebrate OLPC Europe. Just click here if you are on an XO or have the Squeakland plugin installed (as everyone should of course). For those who were there and took the huge file home on their USB drives - this is a fixed version that does not keep growing indefinitely while animating.

For the Etoyers out there - if you put a copy of a player in one of its own variables repeatedly, this creates an evergrowing "linked list" of player copies. Bad idea. Reset the variable first (by assigning dot for example) then do the copy: see my example.

OLPC review now online, English too

The extensive OLPC article by c't magazine is now available online in both original German and an English translation. It's a thorough review (they had a B1 machine) with some interesting photographs in it, like the Squeak Etoys screen in reflective and backlight modes with microscopic images revealing the working of the XO's incredible LCD.

Croquet SDK 1.0 released

Get it while it's hot from the equally new Croquet Consortium web site.

In-depth review of XO in German c't magazine

There's a glowing review of the OLPC project and its XO machine in the current issue 07/2007 of c't magazine. The in-depth article by Dr. Jürgen Rink describes the project's history and educational ambitions as well as its current prototype hardware and software. One very interesting detail is a comparison of the XO's novel dual-mode display in low light and bright sun light, at normal size and magnified:
On the left, under indoor lighting, the colored backlight shines through holes in the reflective layer. On the right, when brightly lit outdoors, the reflection is so strong that the backlight is not even visible anymore, thus creating a gray-scale image. The photographs show one of the example Etoys projects.

The magazine is available now at kiosks until next week, or via mail order. In a few weeks the article should be available online via click&buy.

Croquet for Business: Qwaq Forums

So Qwaq came out of "stealth-mode" and reveiled what they have been working on for a while now, Qwaq Forums:

Qwaq Forums, the company's first product, is a secure virtual workspace application that significantly increases the productivity of distributed teams by bringing critical resources together in virtual places, as if they were in an actual physical location. A highly interactive and persistent environment, Qwaq Forums enables users to work, collaborate with others, and identify and solve problems.

And I'm proud to say I contributed a little, which most probably will find its way into the next Croquet release.

Update: Here's a few nice stories of fellow bloggers who have seen Forums already.

From Steve Borsch's Connecting The Dots:

Qwaq will get traction only because they completely understand that giving someone a semi-trailer truck (i.e., an engine like There or Second Life) doesn't do much good if the person has a small garage and needs a vehicle to go get groceries and tool around (90% of collaborators). Qwaq Forums is a powerful, easy to use and navigate, co-creation space that the rest of us can use.

Glyn Moody writes on Open dot dot dot:

One of the benefits of using Croquet as the basis of its products is that the protocols are open, and this allows Croquet-compatible products to interoperate with Qwaq's. This means that the dynamics of the Croquet ecosystem are similar to that of the Web, which is never a bad thing.

And in The Culture of Collaboration, Evan Rosen writes:

Unlike most traditional web conferencing which works only while a session is underway, Qwaq Forums is persistent. This means authorized users can access the virtual space any time. Team members in another time zone may wake up to find the results of real-time collaboration that occurred while they were sleeping.

Interactive OLPC XO Display Simulation

Many people still have not seen the innovative display of the OLPC project's "XO" laptop. It has twice the resolution of a regular LCD (200 dpi), and works in bright daylight in gray-scale reflective mode. It's impossible for me to increase your screen's resolution by software, and I cannot make your display reflective, but here is an interactive simulation of the backlight mode with its interesting color pattern. This pattern is the source of a lot of confusion about the "color resolution" of the display. The LCD has 1200x900 square pixels, but the backlight puts a full color through each pixel. It is not made of red, green, and blue sub-pixels like a regular LCD, but the first pixel is full red, the second green, the third blue, and so on. The DCON chip (Display CONtroller) selects the color components from the full-color frame buffer.

My simulation of the DCON achieves the same effect by selecting either the red, green, or blue color component in each pixel. Just move the mouse pointer around to see how different colors are reproduced. You'll notice strong diagonal patterns, but remember, on the actual display the pixels are only half as large. Note that the actual DCON optionally applies a bit of anti-aliasing in hardware which is not simulated here. It helps reproducing fine structures and depicts colors more accurately. Additionally, the simulation shows a magnified image to better illustrate the principle, but it is not accurate because the reflective area of each pixel is not depicted. Maybe I can add this in a later version.

I made the simulation using Squeak / Etoys, which is one of the programming environments on the OLPC machine, but also works on Windows, Mac OS X, Linux, and many more systems. If you run the simulation on the actual laptop (download the project, place it in /home/olpc/.sugar/default/etoys/MyEtoys, run Etoys, choose Load Project), then you should close the small simulated screen and just leave the magnified view open.

For the interactive simulation, download Squeak (this version installs both, a regular application and a browser plugin), then click here to run the simulation in your browser, or download the project file, launch Squeak, and drop the project into it.

Intel-Mac users beware, the plugin is not supported directly yet. To see the project in Safari, you have to quit Safari, set it to open in Rosetta (select Safari in the finder, press Cmd-i), and reopen. Or, use the download method, Squeak itself is running fine on Intel Mac, it's just the browser plugin that's making problems.

OpenGL in a Workspace

On some modern Linux systems, Croquet does not work anymore because OpenGL failes to initialize. Now, I originally wrote that code, and it worked fine for years. So it can't possibly be buggy, right? Jens Lincke of impara tracked it down to the "Composite" extension that is enabled by default nowadays. With Composite disabled, it works, enable it, and it does not.

So I turned to NVIDIA for help, thinking their driver might be buggy. Had to give them an easy way to reproduce the problem, this is the snippet I came up with:

| ogl green |
ogl := OpenGL newIn: (0@0 extent: 100@100).
green := 1.
[[
        ogl glClearColor(0, green, 0, 1).
        ogl glClear(16r4000).
        ogl swapBuffers.
        Sensor waitClickButton.
        green := 1 - green.
] repeat] ensure: [ogl destroy]

Beauty, eh? ;-) I guess nobody has done this in a workspace for a long time. Stop it with Alt-.

Anyway, NVIDIA could reproduce the problem, and found our bug:

[...] the app is trying to create a depth 24 child window of a depth 32 parent and the app specifies neither a border pixel nor a border pixmap.

Doh! I forgot to specify the border! We were just lucky that this did not happen before. Jens and y.t. made a patch, should be in the next VM. And big thanks to NVIDIA developer support!

Stripped XO

Early in January, my laptop was the star of a photo shooting for the German issue of MIT's Technology Review. We took off the plastic enclosure of the "brick", it was pretty interesting, for example to see how the whole display in its metallic housing is carefully held by rubber mounts.

This photograph was published in the magazin's current issue (02/07), along with a shot of the main board (which sits behind the display). The accompanying text not only provided a description of the parts, but also highlighted some design decisions that makes it unique hardware-wise. OLPC's educational goals were already reported on in the previous issue.




Image courtesy of http://www.heise.de/tr/magazin/

The colors are off for some reason after uploading to blogger - they were fine on my disk. Sorry.