12 Nov 2010
My kids’ favorite piece of educational software is
“Clifford The Big Red Dog Thinking Adventures” by
Scholastic. We received it as a hand-me-down from their cousins. The CD was
designed for Windows 95-98 and pre-OSX Macintosh. Unfortunately, it does not
run on OS X 10.6. (I think it fails to run because it uses the PowerPC
instruction set and Apple dropped support for emulating that instruction set
in 10.6.)
After some trial and error, I found the most reliable way to run Clifford on
my Mac was:
- Install VMWare Fusion.
- Install Ubuntu 10.10 32-bit in a Virtual Machine.
- Install the VMWare Additions to make Ubuntu work better in the VM.
- Install Wine on Ubuntu 10.10. (Wine provides partial Windows API emulation for Linux.)
- Configure the audio for Wine. (I accepted the defaults.)
- Insert the Clifford CD and manually run the installer.
The result is that the Clifford game runs full screen with smooth animation
and audio, even on my lowly first-generation Intel Mac Mini.
You may scoff at all these steps, but (a) it’s cheap, and (b) it’s less work
than installing and maintaining a Windows PC or VM just to play this one game.
(It’s too bad there isn’t a Flash, HTML5, Android or iOS version of this game,
it’s really quite well done.)
06 Sep 2010
This Labor Day weekend I decommissioned my tower PC.
If memory serves, I bought it in the summer of 2002, in one last burst of PC
hobby hacking before the birth of my first child. It’s served me and my
growing family well over the years, first as my main machine, later as a media
server.
But the world has changed, and it doesn’t make much sense to keep it running
any more. It’s been turned off for the last year while I traveled to Taiwan.
In that time I’ve learned to live without it.
The specific reasons for decommissioning it now are:
- It needs a new CMOS battery.
- It needs a year’s worth of Vista service packs and security updates.
- I don’t use the media center feature any more.
- After a year without a Windows machine I don’t want to maintain one any more.
- It’s too noisy and uses too much energy to leave on as a server.
The decommissioning process
I booted it, and combed through the directories. I carefully copied off all
the photos, code projects, email and documents that had accumulated over the
years. Lots of good memories!
GMail Import
I discovered some old Outlook Express message archives. I wrote a Python
script to import them into GMail. I didn’t like any of the complicated recipes
I found on the web, so I did it the easy way: I wrote a toy POP3 server in
Python that served the “.eml” messages from the archive directory. Once the
toy POP3 server was running, GMail was happy to import all the email messages
from my server.
Erasing the disks with Parted Magic
Once I was sure I had copied all my data off the machine it was time to erase
the disks. I erased the disks using the
ATA Secure Erase command. I did
this using a small Linux distro, Parted Magic. I
downloaded the distribution ISO file and burned my own CD. Once the CD was
burned, I just rebooted the PC and it loaded Parted Magic from the CD.
Parted Magic has a menu item, “Erase Disk”. It lets you choose the disk and
the erase method. The last method listed is the one I used. The other methods
work too, but they don’t use the ATA Secure Erase command.
It took quite a while to erase the disks. Each disk took about two hours to
erase. (They took 200 GB per hour, to be precise.) Unfortunately, due to the
limitations of my ATA drivers, I had to erase them one at a time.
While I think the ATA Secure Erase command is the fastest and most reliable
way to erase modern hard disks, there is another way: Instead of having the
drive erase itself, you can copy data over every sector of the drive. The
advantage of this technique is that it also works with older drives. If you
choose to go this route, one of the easiest way to do it is to use
Darik’s Boot and Nuke utility. This is a Linux distro that does
nothing besides erasing all the hard disks of the computer you boot it on. You
just boot the CD, then type “autonuke” to erase every disk connected to your
computer.
Disposing of the computer
It’s still a viable computer, so I will probably donate it to a local charity.
The charity has a rule that the computer you donate must be less than 5 years
old. I think while some parts of the computer are older than that, most of the
parts are young enough to qualify.
Reflections on the desktop PC platform
Being able to upgrade the PC over the years is a big advantage of the
traditional desktop tower form factor. Here’s how I upgraded it over the
years:
Initial specs (2002)
- Windows XP
- ASUS P4S533 motherboard
- Pentium 4 at 1.8 GHz
- ATI 9700 GPU
- Dell 2001 monitor (1600 x 1200)
- 256 MB RAM
- 20 GB PATA HD
- Generic case
Final specs (2010)
- Windows Vista Ultimate
- ASUS P4S533 motherboard
- Pentium 4 at 1.8 GHz
- ATI 9700 GPU
- Dell 2001 monitor (1600 x 1200)
- 1.5 GB RAM
- 400 GB 7200 RPM PATA HD
- 300 GB 7200 RPM PATA HD
- ATI TV Theater analog capture card
- Linksys Gigabit Ethernet PCI card
- Antec Sonata quiet case
I think these specs show the problems endemic to the desktop PC market.
Although I didn’t know it at the time, the PC platform had already plateaued.
In eight years of use I wasn’t motivated to upgrade the CPU, motherboard,
monitor, or GPU. If I hadn’t been a Microsoft employee during part of this
time I wouldn’t have upgraded the OS either.
What killed the PC for me wasn’t the hardware wearing out, it was mission
change. Like most people I now use the web rather than the local PC for most
of my computer activity. Maintaining the local PC is pure overhead, and I’ve
found it’s easier to maintain a Mac than a PC.
It was nostalgic to turn on the PC again and poke through the Vista UI. It
brought back some good memories. (And I discovered some cute pictures of my
kids that I’d forgotten about.)
Thank you trusty PC. You served me and my family well!
29 Aug 2010
It’s been a year since
I bought my fancy car stereo.
I wanted to mention that I’ve ended up not using most of the fancy features.
- The built-in MP3 player had issues with my 1000-song / 100 album / 4 GB music collection:
- It took a long time to scan the USB storage each time the radio turned on.
- It was difficult to navigate the album and song lists.
- Chinese characters were not supported.
- It took a long time to “continue” a paused item, especially a long item like a podcast.
- The bluetooth pairing only worked with one phone at a time, which was awkward in a two-driver family.
Here’s how I use it now:
- I connect my phone using both the radio’s USB (so the phone is being charged) and mini stereo plugs.
- I use the phone’s built-in music player.
- I have the radio set to AUX to play the music from the stereo input plug.
It’s a little bit cluttered, because of the two cables, but it gets the job
done. The phone’s music player UI is so much better than the radio’s UI.
In effect I have reduced the car stereo to serving as a volume control, an
amplifier, and a USB charger.
25 Jul 2010
I just returned to the US after eight months living in Taiwan. The trip was
great fun for me and my family. But more than that, it was a very productive
time for me to learn new programming technologies.
Why was my trip so productive?
I think some of the reasons were:
- I was away from my home computer set up (including video game consoles and a large TV). All I had was a Mac Mini (for the family to use), a MacBook Pro (for work) and a Nexus One phone.
- I commuted by bus rather than car. While my commute time was longer, it was much more productive. Instead of having to concentrate on driving, I had 40 minutes a day of free time to think, web surf, and even code.
- I didn’t follow local politics, and USA politics were made less interesting by distance and time zone. I stopped visiting political web sites and obsessing over current events.
- The timezone difference between Taipei and the US ment that email became a once-a-day event, rather than a continuous stream of interruptions.
- It’s more time-efficient to live as a guest in a city than as a home owner in the suburbs. For example, my mother-in-law cooked our meals, and I didn’t have nearly as many household chores as I do in America.
- Location-based internet blocks ment that some of my favorite time-wasting web sites (Pandora, Hulu) were unavailable.
- Having to explain and defend my technology opinions to my Google Taipei coworkers. “Go is a cool language” I would say. “Oh yeah? Why?” they would reply. I would struggle to explain, and usually both of us would end up more enlightened.
Beyond that, I think being in a new environment, and removed from my home,
helped shake me loose from my mental ruts. I was learning how to live in a new
physical environment, and that transfered over to how I used the web as well.
What did I do?
- I visited Hacker News frequently. It is a very good source of news on the startup business and new web technologies. Hacker News was where I first learned about Node.js and CoffeeScript, two of my current interests.
- I entered the Google AI Challenge, a month long Game AI programming contest. I didn’t place very high, but I had fun competing.
- I gave two talks on the Go programming language. One at the Google Taiwan office, the other at the Open Source Developer Conference Taiwan OSDC.tw. Having to give a talk about a programming language helps increase one’s understanding of that language.
- An afternoon spent hanging out with JavaScript Mahatma Douglas Crockford. I worked with Douglas ages ago when we both worked at Atari. It was great to catch up with him and his work. (He was in town to give a speech at the OSDC conference.)
- I joined GitHub, and started using it to host my new open source projects.
- I wrote Taipei-Torrent, a Bit Torrent client written in “Go”.
- I started summerTorrent, a Bit Torrent client written in JavaScript, based on node.js
- node.js - an interesting server-side JavaScript environment.
- CoffeeScript - a JavaScript preprocessor that looks like a promising language.
- PhoneGap - a cross-platform mobile JavaScript / HTML5 UI framework. I wrote a word scramble game using this framework.
- DD-WRT routers. I bought four new DLink 300 routers (which are dirt cheap), installed DD-WRT on them, and used them to upgrade my Taiwan relatives’ computer network.
- My nephew bought a PS3, so I finally had a chance to see Little Big Planet and Flower, two games I had long wanted to know more about. I also got to see a lot of Guitar Hero being played. Unfortunately I didn’t get a chance to actually play any of these games – someone else always had a higher claim on the TV.
Keeping the Taipei Experience Alive
I’m back in the US, and am already starting to slip back into my old ways.
Here are some ways I’m trying to keep my productivity up:
- Cool side projects.
- I’m going to continue to work on side projects to learn new things. I want to do something serious with CoffeeScript and Node.js.
- iPad. I’m getting one in a few weeks, and looking to see if its a useful paradigm.
- Get rid of distractions.
- I’m selling off (or just closeting) distractions like my older computers and my media center.
- I edited my /etc/hosts file to block access to all my top time-wasting web sites. Hopefully I won’t just replace these with a new generation of web sites.
- Working at home. My work office here in the US is just too noisy for me to concentrate in. I’m going to start spending as much time as possible working from a quiet room at home.
- Regular exercise. I got a lot of walking done in Taiwan. I’m going to take up running again. (Easy to do now, we’ll see how it goes when the weather gets rough.)
- I may even get a pair of “Gorilla Shoes” for barefoot running.
18 Jun 2010
The ICFP 2010 contest rules have been posted,
and I am quite disappointed by this year’s contest.
This year’s contest is difficult to describe. It’s too clever by half, and it
depends too much on time, and too much on repeated interaction with the
organizer’s servers.
The conceit is that you’re designing “car engines”, and “fuel for car
engines”. A car engine is a directed graph with certain properties, and “fuel”
is a directed graph with other properties that generates a set of coefficients
that are fed to the engine.
Layered on top of that is an encoding puzzle (you have to figure out how the
engine and fuel directed graphs are encoded for submission to the IFCP
servers.)
Layered on top of that is an economy where you are encouraged to submit your
own car engines and write optimal fuels for other people’s car engines. There
are benefits for finding better fuels for existing car designs. (You aren’t
provided the details of the other car designs.)
Layered on top of that is that the instructions are not written very clearly.
I had to read them multiple times to start to even begin to understand what
was going on.
And finally, the contest registration / submission web site is returning 503
(Service Temporarily Unavailable) errors, either because it hasn’t been turned
on yet, or perhaps because hundreds of teams are trying to use it at once.
I suspect this contest is going to be difficult for teams with limited
Internet connectivity. I also suspect the contest servers are going to be very
busy later in the contest as people start hitting them with automated tools
repeatedly in order to start decoding engines.
I salute the contest organizers for trying to get contestants to interact with
each other during the contest, and for coming up with an original idea.
I fault them for designing a “write your program in our language, not yours”
puzzle. I want to enjoy programming in the language of my choice, not design
graphs and finite state automata for creating fuel coefficients and engines.
I am going to punt this year – the contest just doesn’t sound very fun.
I hope next year’s topic is more to my taste!
08 May 2010
Happy Mother’s Day everyone! This year I wrote an Android app for my wife for
Mother’s Day. How geeky is that?
The reason I wrote it is that my wife’s favorite Android application, Word Mix
Lite, recently added annoying banner ads. While the sensible thing to do might
have been to switch to another app, or perhaps upgrade to the paid version of
Word Mix, I thought it might be interesting to see if I could write my own
replacement.
And as long as I was writing the app, I though I’d try writing it using
JavaScript. Normally Android applications are written in Java, but it’s also
possible to write them in JavaScript, by using a shell application such as
PhoneGap.
Why use JavaScript instead of Java? Well, hack value mostly. On the plus side
it’s a fun to write! Another potential plus is that it is theoretically
possible to run the same PhoneGap application on both Android and Apple.
The drawback is that PhoneGap is not very popular yet, especially among
Android developers, and so there is relatively little documentation. I ran
into problems related to touch events and click events that I still haven’t
completely solved.
It took about three days to write the application. The first day was spent:
- Finding a public domain word list.
- Filtering the word list to just 3-to-6 character words.
- Build a “trie” to make it fast to look up anagrams.
- Output the trie as a JSON data structure.
The second day was spent writing the core of the word jumble game.
- This was all done on a desktop, using Chrome’s built-in Javascript IDE.
The third day was spent:
- Porting to PhoneGap.
- Debugging Android-specific issues.
- Tuning the gameplay for the phone.
The project went pretty well.
- JavaScript is a very easy language to work in.
- CSS styling was fairly easy to learn.
- Targeting a single browser made it relatively easy to use the DOM.
- The Chrome JavaScript debugger was very helpful.
- The web has a wealth of information on JavaScript and HTML / CSS programming information.
In the end there were unfortunately a few button-event UI glitches I couldn’t
solve in time for Mother’s Day. When I get some spare time I’d like to revisit
this project and see if I could use the JQTouch
library to solve my UI glitches. I’d also like to make an open source release
of a reskinned (non-Mother’s Day themed) version of this app. And then who
knows? Maybe I’ll release it for the other phones that PhoneGap supports as
well. :-)
06 Mar 2010
Team Blue Iris
(that’s me!) placed 77th out of 708 in the
Google AI Challenge 2010 contest. The contest was to design
an AI for a Tron lightcycle game.
My entry used the standard min/max approach, similar to many other entries. I
guess that’s why it performed similarly to so many other entries. :-) I didn’t
have any time to investigate better algorithms, due to other obligations.
In addition to my own entry (which was in C++), I also created starter packs
for JavaScript and Google’s Go language. These starter packs enabled people to
enter the contest using JavaScript or Go. In the end,
6 people entered using Go, and
4 people entered using JavaScript.
I’m pleased to have helped people compete using these languages.
I initially wanted to use JavaScript and/or Go myself, but the strict time
limit of the contest strongly favored the fastest language, and that made me
choose a C++ implementation. Practically speaking, there wasn’t much advantage
to using another language. The problem didn’t require any complicated data
structures, closures, or dynamic memory allocation. And the submitted entries
were run on a single-hardware-thread virtual machine, which meant that there
wasn’t a performance benefit for using threads.
This contest was interesting because it went on for a long time (about a
month) and because the contestants freely shared algorithm advice during the
contest. This lead to steadily improving opponents. My program peaked at about
20th place early in the contest, but because I didn’t improve it thereafter,
its rank gradually declined over the rest of the contest.
The contest winner’s post-mortem
reveals that he won by diligent trial-and-error in creating a superior evaluation function. Good
job a1k0n!
Congratulations to the contest organizers for running an interesting contest
very well. I look forward to seeing new contests from the University of
Waterloo Computer Club in the future.
23 Jan 2010
I wanted to learn more about how the original BitTorrent client implemented
“choking”, so I downloaded the source to the original Python-based BitTorrent
client from SourceForge.
I was impressed, as always, by the brevity and clarity of Python. The original
BitTorrent client sources are very easy to read. (Especially now that I
understand the problem domain pretty well.) The code has a nice OO design,
with a clear separation of responsibilities.
I was also impressed by the extensive use of unit tests. About half the code
in the BitTorrent source is unit tests of the different classes, to make sure
that the program behaves correctly. This is a really good idea when developing
a peer-to-peer application. The synthetic tests let you test things like your
end-of-torrent logic immediately, rather than by having to find an active
torrent swarm and wait for a real-world torrent to complete.
When I get a chance I’m going to refactor the Taipei-Torrent code into smaller
classes and add unit tests like the original BitTorrent client implementation
has.
And come to think of it, why didn’t I check out the original BitTorrent client
code sooner? It would have saved me some time and I’d probably have a better
result. D’Oh! Oh well, live and learn!
23 Jan 2010
From Scientific American:
Binary Body Double: Microsoft Reveals the Science Behind Project Natal
Short summary: They used machine-learning algorithms and lots of training data
to come up with an algorithm that converts moving images into moving joint
skeletons.
Given the huge variation in human body shapes and clothing, it will be
interesting to see how well this performs in practice.
I bet people will have a lot of fun aiming the Natal camera at random moving
object to see what happens. I can already imagine the split-screen YouTube
videos we’ll see of Natal recognizing pets, prerecorded videos of people,
puppets and marionettes.
Oh, and of course, people will point Natal back at the TV screen and see if
the video game character can control itself.
Great fun!
22 Jan 2010
Wow, my Taipei-Torrent post made it to Hacker News and
reddit.com/r/programming. I’m thrilled!
One comment on Hacker News was “800 lines for a bencode serializer?! It only
took me 50 lines of Smalltalk!” That was a good comment! I replied:
A go bencode serialization library could be smaller if it just serialized
the bencode data to and from a generic dictionary container. I think another
go BitTorrent client, gobit, takes this approach.
But it’s convenient to be able to serialize arbitrary application types.
That makes the bencode library larger because of the need to use go’s
reflection APIs to analyze and access the application types. Go’s reflection
APIs are pretty verbose, which is why the line count is so high.
To make things even more complicated, the BitTorrent protocol has a funny
“compute-the-sha1-of-the-info-dictionary” requirement that forces BitTorrent
clients to parse that particular part of the BitTorrent protocol using a
generic parser.
So in the end, the go bencode serializer supports both a generic dictionary
parser and an application type parser, which makes it even larger.
In general, Taipei-Torrent was not written to minimize lines-of-code. (If
anything, I was trying to maximize functionality per unit of coding time.) One
example of not minimizing lines-of-code is that I used a verbose error
handling idiom:
a, err := f()
if err != nil {
return
}
There are alternative ways to handle errors in go. Some of the alternatives
take fewer lines of code in some situations. The above idiom is my preference
because it works correctly in all cases. But it has the drawback of adding 3
lines of code to every function call that might return an error.
The go authors are considering adding exceptions to the go language. If they
do so it will probably dramatically improve the line count of Taipei-Torrent.