file page 34 - Dave's Blog

Facebook Profile Views Application - Failed Idea

I had an idea for a Facebook app the other day. I wondered who actually looked at my profile and thought I could create a Facebook app that would record this information and display it. When I talked to Vishu though he said that this wasn't something that Facebook would be too happy with. Indeed the Platform Policy explicitly disallows this in section 2.8. This explained why the app didn't already exist. Its probably for the best since everyone assumes they can anonymously view Facebook profiles and would be irritated if that weren't the case.

On the topic of assumed anonymity, check out this article on the aggregation and selling off of your cell phone data including your physical location.

Leaking Information Through Delicious

While re-reading Cryptonomicon I thought about what kind of information I'm leaking by posting links on Delicious. At work I don't post any Intranet websites for fear of revealing anything but I wondered if not posting would reveal anything. For instance, if I'm particularly busy at work might I post less indicating something about the state of the things I work on? I got an archive of my Delicious posts via the Delicious API and then ran it through a tool I made to create a couple of tables which I've graphed on Many Eyes

Encoding methods in C#

For Encode-O-Matic, my encoding tool written in C#, I had to figure out the appropriate DllImport declarations to use IDN Win32 functions which was a pain. To spare others that pain here's the two files CharacterSetEncoding.cs and NationalLanguageSupportUtilities.cs that declare the DllImports for IdnToUnicode, IdnToAscii, NormalizeString, MultiByteToWideChar, and WideCharToMultiByte.

Zeno's Progress Bar - Stolen Thoughts

More of my thoughts have been stolen: In my previous job the customer wanted a progress bar displayed while information was copied off of proprietary hardware, during which the software didn't get any indication of progress until the copy was finished. I joked (mostly) that we could display a progress bar that continuously slows down and never quite reaches the end until we know we're done getting info from the hardware. The amount of progress would be a function of time where as time approaches infinity, progress approaches a value of at most 100 percent.

This is similar to Zeno's Paradox which says you can't cross a room because to do so first you must cross half the room, then you must cross half the remaining distance, then half the remaining again, and so on which means you must take an infinite number of steps. There's also an old joke inspired by Zeno's Paradox. The joke is the prototypical engineering vs sciences joke and is moderately humorous, but I think the fact that Wolfram has an interactive applet demonstrating the joke is funnier than the joke itself.

I recently found Lou Franco's blog post "Using Zeno's Paradox For Progress Bars" which covers the same concept as Zeno's Progress Bar but with real code. Apparently Lou wasn't making a joke and actually used this progress bar in an application. A progress bar that doesn't accurately represent progress seems dishonest. In cases like the Vista Defrag where the software can't make a reasonable guess about how long a process will take the software shouldn't display a progress bar.

Similarly a paper by Chris Harrison "Rethinking the Progress Bar" suggests that if a progress bar speeds up towards the end the user will perceive the operation as taking less time. The paper is interesting, but as in the previous case, I'd rather have progress accurately represented even if it means the user doesn't perceive the operation as being as fast.

Update: I should be clearer about Lou's post. He was actually making a practical and implementable suggestion as to how to handle the case of displaying progress when you have some idea of how long it will take but no indications of progress, whereas my suggestion is impractical and more of a joke concerning displaying progress with no indication of progress nor a general idea of how long it will take.

Feed Folder Deprecated; Use Internet Explorer 8

Internet Explorer 8 has made my plugin Feed Folder obselete in functionality and implementation -- which is good!

I made Feed Folder for IE7 because I wanted the Live Bookmarking feature from FireFox. The Feed Folder plugin for IE7 would allow you to display your feeds as virtual folders in your Links Bar. When your feed is updated the virtual folder is updated as well with the new feed items. I use del.icio.us to store all my links so I could add virtual folders of my daily links, my friends blogs links, quick reference links, etc. etc.

My plugin relied on shell folders to implement the virtual folders I described above, but IE8 doesn't support shell folders in the Favorites Bar. But I'm OK with Feed Folder not working in IE8 since there's a much better implementation already there. IE8 does better than my plugin on a number of points: First, there isn't the horrible perf. issue that my plugin had on Vista. Second, when a feed is updated the virtual folder flashes to note the change in status. Third, unread items are bolded and the bolding bubbles up from feeds contained in subfolders. And lastly, the middle click button is supported to open items in a new tab.

Accordingly, I don't plan to work on Feed Folder anymore unless someone comes up with a good reason. Instead I mark Feed Folder deprecated and suggest you use Internet Explorer 8 instead.

To use this feature in IE8 simply drag a feed from your feed list in your Favorites Center onto your Favorites Bar. Or, when viewing a feed, click on the 'Add to Favorites' Star Plus icon thing in the upper left, and select 'Monitor on Favorites Bar'. A .url Internet Shortcut file is produced as usual, but if you open up the .url file you'll see there's some additional info about the feed.

Juanita Beach Visit and Map

Two weekends ago it was actually sunny and kind of warm so Sarah and I went down to Spud Fish and Chips and Juanita Beach Park. We ate fish and chips on the dock. I took a few pictures and this time actually put some geographical information on Flickr so now I've got a map of my tiny fish and chips journey. On the map click on the floating marks to view the associated photos.

Flickr provides access to the geo data associated with your photos via GeoRSS feeds. And Google Maps displays GeoRSS feed content on their maps allowing you even to edit the data but doesn't appear to let you easily export the GeoRSS. Live Maps does the inverse, allowing you to create and export GeoRSS data but not import it. I'd like both please. Oh well.

URI Addressable Text Adventure Games

This post is about creating a server side z-code interpreter that represents game progress in the URI. Try it with the game Lost Pig.

I enjoy working on URIs and have the mug to prove it. Along those lines I've combined thoughts on URIs with interactive fiction. I have a limited amount of experience with Inform which generates Z-Code so I'll focus on pieces written in that. Of course we can already have URIs identifying the Z-Code files themselves, but I want URIs to identify my place in a piece of interactive fiction. The proper way to do this would be to give Z-Code its own mimetype and associate with that mimetype the format of a fragment that would contain the save state of user's interactive fiction session. A user would install a browser plugin that would generate URIs containing the appropriate fragment while you play the IF piece and be able to load URIs identifying Z-Code files and load the save state that appears in the fragment.

But all of that would be a lot of work, so I made a server side version that approximates this. On the Web Frotz Interpreter page, enter the URI of a Z-Code file to start a game. Enter your commands into the input text box at the bottom and you get a new URI after every command. For example, here's the beginning of Zork. I'm running a slightly modified version of the Unix version of Frotz. Baf's Guide to the IF Archive has lists of IF games to try out.

There are two issues with this thought, the first being the security issues with running arbitrary z-code and the second is the practical URI length limit of about 2K in IE. From the Z-Code standard and the Frotz source it looks like 'save' and 'restore' are the only commands that could do anything interesting outside of the Z-Code virtual machine. As for the length-limit on URIs I'm not sure that much can be done about that. I'm using a base64 encoded copy of the compressed input stream in the URI now. Switching to the actual save state might be smaller after enough user input.

Chumby will be cool, despite its name

I signed up for the pre-release beta and purchased a Chumby last year. Chumby looks like a cousin to a GPS unit. Its similar in size with a touch screen, but has WiFi, accelerometers, and is pillow like on the sides that aren't a screen. In practice its like an Internet alarm clock that shows you photos and videos off the Web. Its hackable in that Chumby Industries tells you about the various ways to run your own stuff on the Chumby, modifying the boot sequence (it runs Linux), turning on sshd, etc, etc. The Chumby forum too has lots of info from folks who have found interesting hacks for the device.

When you turn on the Chumby it downloads and runs the latest version of the Chumby software which lets you set alarms, play music, and display Flash widgets. The Chumby website lets anyone upload their own Flash widgets to share with the community. I tried my hand at creating one using Adobe's free Flash creation SDK but I don't know Flash and didn't have the patience to learn.

Currently my Chumby is set to wake me up at 8am on weekdays with music from ShoutCast and then displays traffic and weather. At 10am everyday it switches to showing me a slide-show of LolCats. At 11pm it switches to night mode where it displays the time in dark grey text on a black background at a reduced light level so as not to disturb me while I sleep.

I like the Chumby but I have two complaints. The first is that it forces me to learn flash in order to create anything cool rather than having a built-in Web browser or depending on a more Web friendly technology. The second complaint is about its name. At first I thought the name was stupid in a kind of silly way, but now that I'm used to the name it sounds vaguely dirty.

LibraryThing Developers are Responsive

I use my recently added books feed from LibraryThing, a site I've mentioned before where you track, review, recommend, and share your books, and I put the recently added books on my page. I thought it might be nice to include the book covers so I suggested adding book covers to RSS feeds in LibraryThings 'Recommend Site Improvements' group. The next day I had a response from the founder and lead developer Tim Spalding who had started implementing the feature. I noticed a few bugs, reported them on the same thread, and he fixed them soon after. Fantastic! It makes me want to upgrade to a paying account.

Incidentally, if you notice the Ghost in the Shell book appear multiple times in my RSS feed its due to the previously mentioned iterative bug fixes. The same item appeared multiple times slightly differently with each bug fix and your RSS aggregator may have picked them up as distinct items.