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npr:The jobs picture has changed profoundly since the 1970s....

2015 Feb 6, 10:50


npr:

The jobs picture has changed profoundly since the 1970s. This map shows how that has played out across the country.

Map: The Most Common Job In Every State

Source: IPUMS-CPS/ University Of Minnesota
Credit: Quoctrung Bui/NPR

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Tweet from David_Risney

2015 Feb 1, 2:22
My 3yo playing hide & seek today: waits for finder to count then jumps out from hiding spot to scare finder. World class hide & seek player!
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Polygon: Ready Player One sequel in the works, says movie screenwriter

2015 Jan 16, 3:00
Polygon        ✔ @Polygon :
Ready Player One sequel in the works, says movie screenwriter http://polygon.com/e/7324396  pic.twitter.com/aOKU3hm5p5
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Quadrilateral Cowboy gameplay video “Quadrilateral Cowboy...

2014 Oct 6, 2:41


Quadrilateral Cowboy gameplay video

“Quadrilateral Cowboy is a game we’ve been watching with great interest ever since Thirty Flights Of Loving creator Brendon Chung first debuted it last year. It’s about hacking, but not via irritating minigames or jargon-your-problems-away Hollywood magic. Instead, you learn basic (albeit fictional) code and take down everything from laser grids to gun emplacements with a twitch of your fingers and a wriggle of your brain. It’s already an extremely clever game, and it’s quite empowering despite the fact that you play as someone who probably couldn’t even heft an assault rifle - let alone fire one. Basically, it’s a wonderfully novel idea - more Neuromancer than Deus Ex - but words only do it so much justice. Thus, I’ve decided to play it for your enrichment, in hopes that you will understand why Quadrilateral should be driving your radar haywire.”

PermalinkCommentsgame video-game hack computer

Gamers Messed With The Steam Sale, Then Valve Changed The Rules

2014 Jun 24, 3:51

Applied game theory 101: Valve’s Steam Summer Sale involves a meta game with teams of Steam users competing for daily prizes. On Reddit the players join together to take turns winning daily. Valve gets wise and performs an existential attack, changing the rules to make it harder for players to want to coordinate.

Still, that all the players joined together to game the system gives me hope for humanity. Its a self organized solution to a tragedy of the commons problem. Only in this case the tragedy is by design and is updated to be more tragic.

PermalinkCommentsgame video-game game-theory valve

ios - Capture image via captureStillImageAsynchronouslyFromConnection with no shutter sound - Stack Overflow

2014 May 24, 2:42

The best hack I’ve seen in a while. With no way to disable the shutter sound from the capture photo API, the developer creates the inverse waveform of the shutter sound and plays it at the same time to cancel out the shutter sound.

PermalinkCommentstechnical humor ios photo sound

Debugging anecdote - the color transparent black breaks accessibility

2014 May 22, 10:36

Some time back while I was working on getting the Javascript Windows Store app platform running on Windows Phone (now available on the last Windows Phone release!) I had an interesting bug that in retrospect is amusing.

I had just finished a work item to get accessibility working for JS WinPhone apps when I got a new bug: With some set of JS apps, accessibility appeared to be totally broken. At that time in development the only mechanism we had to test accessibility was a test tool that runs on the PC, connects to the phone, and dumps out the accessibility tree of whatever app is running on the phone. In this bug, the tool would spin for a while and then timeout with an error and no accessibility information.

My first thought was this was an issue in my new accessibility code. However, debugging with breakpoints on my code I could see none of my code was run nor the code that should call it. The code that called that code was a more generic messaging system that hit my breakpoints constantly.

Rather than trying to work backward from the failure point, I decided to try and narrow down the repro and work forwards from there. One thing all the apps with the bug had in common was their usage of WinJS, but not all WinJS apps demonstrated the issue. Using a binary search approach on one such app I removed unrelated app code until all that was left was the app's usage of the WinJS AppBar and the bug still occurred. I replaced the WinJS AppBar usage with direct usage of the underlying AppBar WinRT APIs and continued.

Only some calls to the AppBar WinRT object produced the issue:

        var appBar = Windows.UI.WebUI.Core.WebUICommandBar.getForCurrentView(); 
// appBar.opacity = 1;
// appBar.closeDisplayMode = Windows.UI.WebUI.Core.WebUICommandBarClosedDisplayMode.default;
appBar.backgroundColor = Windows.UI.Colors.white; // Bug!
Just setting the background color appeared to cause the issue and I didn't even have to display the AppBar. Through additional trial and error I was blown away to discover that some colors I would set caused the issue and other colors did not. Black wouldn't cause the issue but transparent black would. So would aqua but not white.

I eventually realized that predefined WinRT color values like Windows.UI.Colors.aqua would cause the issue while JS literal based colors didn't cause the issue (Windows.UI.Color is a WinRT struct which projects in JS as a JS literal object with the struct members as JS object properties so its easy to write something like {r: 0, g: 0, b: 0, a: 0} to make a color) and I had been mixing both in my tests without realizing there would be a difference. I debugged into the backgroundColor property setter that consumed the WinRT color struct to see what was different between Windows.UI.Colors.black and {a: 1, r: 0, g: 0, b: 0} and found the two structs to be byte wise exactly the same.

On a hunch I tried my test app with only a reference to the color and otherwise no interaction with the AppBar and not doing anything with the actual reference to the color: Windows.UI.Colors.black;. This too caused the issue. I knew that the implementation for these WinRT const values live in a DLL and guessed that something in the code to create these predefined colors was causing the issue. I debugged in and no luck. Now I also have experienced crusty code that would do exciting things in its DllMain, the function that's called when a DLL is loaded into the process so I tried modifying my C++ code to simply LoadLibrary the DLL containing the WinRT color definition, windows.ui.xaml.dll and found the bug still occurred! A short lived moment of relief as the world seemed to make sense again.

Debugging into DllMain nothing interesting happened. There were interesting calls in there to be sure, but all of them behind conditions that were false. I was again stumped. On another hunch I tried renaming the DLL and only LoadLibrary'ing it and the bug went away. I took a different DLL renamed it windows.ui.xaml.dll and tried LoadLibrary'ing that and the bug came back. Just the name of the DLL was causing the issue.

I searched for the DLL name in our source code index and found hits in the accessibility tool. Grinning I opened the source to find that the accessibility tool's phone side service was trying to determine if a process belonged to a XAML app or not because XAML apps had a different accessibility contract. It did this by checking to see if windows.ui.xaml.dll was loaded in the target process.

At this point I got to fix my main issue and open several new bugs for the variety of problems I had just run into. This is a how to on writing software that is difficult to debug.

PermalinkCommentsbug debug javascript JS technical windows winrt

Internet Archive lets you play one of the earliest computer...

2014 Apr 28, 9:39


Internet Archive lets you play one of the earliest computer games Space War! emulated in JavaScript in the browser.

This entry covers the historical context of Space War!, and instructions for working with our in-browser emulator. The system doesn’t require installed plugins (although a more powerful machine and recent browser version is suggested).

The JSMESS emulator (a conversion of the larger MESS project) also contains a real-time portrayal of the lights and switches of a Digital PDP-1, as well as links to documentation and manuals for this $800,000 (2014 dollars) minicomputer.

PermalinkCommentscomputer-game game video-game history internet-archive

A Fascinating Look At The World's Best Super Smash Bros. Players

2014 Apr 21, 10:23
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Considerate MessagePort Usage

2013 Aug 7, 7:14
Sharing by leezie5. Two squirrels sharing food hanging from a bird feeder. Used under Creative Commons license Attribution-NonCommercial-NoDerivs 2.0 Generic.When writing a JavaScript library that uses postMessage and the message event, I must be considerate of other JS code that will be running along side my library. I shouldn't assume I'm the only sender and receiver on a caller provided MessagePort object. This means obviously I should use addEventListener("message" rather than the onmessage property (see related What if two programs did this?). But considering the actual messages traveling over the message channel I have the issue of accidentally processing another libraries messages and having another library accidentally process my own message. I have a few options for playing nice in this regard:
Require a caller provided unique MessagePort
This solves the problem but puts a lot of work on the caller who may not notice nor follow this requirement.
Uniquely mark my messages
To ensure I'm acting upon my own messages and not messages that happen to have similar properties as my own, I place a 'type' property on my postMessage data with a value of a URN unique to me and my JS library. Usually because its easy I use a UUID URN. There's no way someone will coincidentally produce this same URN. With this I can be sure I'm not processing someone else's messages. Of course there's no way to modify my postMessage data to prevent another library from accidentally processing my messages as their own. I can only hope they take similar steps as this and see that my messages are not their own.
Use caller provided MessagePort only to upgrade to new unique MessagePort
I can also make my own unique MessagePort for which only my library will have the end points. This does still require the caller to provide an initial message channel over which I can communicate my new unique MessagePort which means I still have the problems above. However it clearly reduces the surface area of the problem since I only need once message to communicate the new MessagePort.
The best solution is likely all of the above.
Photo is Sharing by leezie5. Two squirrels sharing food hanging from a bird feeder. Used under Creative Commons license Attribution-NonCommercial-NoDerivs 2.0 Generic.
PermalinkCommentsDOM html javascript messagechannel postMessage programming technical

solarbird: Perfect.

2013 Jul 28, 1:46


solarbird:

Perfect.

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Percent Clcok Windows Store App Development Notes

2013 Jul 11, 1:00

My third completed Windows Store app is Percent Clock which displays portions of a time span like the time of the day or time until your next birthday, as a percentage. This was a small project I had previously started as a webpage and converted and finished as an HTML JavaScript Windows Store app.

The only somewhat interesting aspect of this app is that its the first app for which I tried charging. I picked the minimum amount for price 1.49 USD as it is a simple app and unsurprisingly it has sold very poorly. I'm considering releasing new instances of the app for specific scenarios:

  • Death Clock: viewing your current age with respect to your life expectancy as a percentage.
  • New Year Countdown: percentage of the year until New Years.
PermalinkCommentsdevelopment javascript technical windows windows-store

This might be the strangest release of classic Chicago label...

2013 May 17, 5:43


This might be the strangest release of classic Chicago label Trax yet! The clue’s in the title - it’s Daft Punk brassified. We get four classics by the world’s most famous Gallic robot duo: “Harder, Better, Faster, Stronger” gets turned into a 1940s Dick Tracy-style riff-off with every form of trumpet imaginable, “Around The World” mixes wind instruments with that famous vocal mantra, “Da Funk” features plenty of sassy brass and “One More Time” wraps things up on a swingin’, jazzy high.

PermalinkCommentsSoundCloud Iamjasonalexander Brass Music music cover daft-punk

laughingsquid: Everybody Wants to Kill Bruce Willis, An Action...

2013 Mar 26, 7:47


laughingsquid:

Everybody Wants to Kill Bruce Willis, An Action Movie Mashup

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Zelda Starring Zelda (by Kenna W) Original NES Legend of Zelda...

2013 Mar 18, 2:17


Zelda Starring Zelda (by Kenna W)

Original NES Legend of Zelda ROM modified to swap Zelda and Link: play as Zelda saving Link.

PermalinkCommentsNintendo rom hack programming Zelda legend-of-zelda

The best cosplay of all time (by RayLiehm) Awesome car...

2012 Nov 14, 5:16


The best cosplay of all time (by RayLiehm)

Awesome car dealership wavy tube thingy costume.

PermalinkCommentshumor costume wavy video

A Slower Speed of Light Official Trailer — MIT Game Lab (by...

2012 Nov 13, 7:41


A Slower Speed of Light Official Trailer — MIT Game Lab (by Steven Schirra)

“A Slower Speed of Light is a first-person game in which players navigate a 3D space while picking up orbs that reduce the speed of light in increments. A custom-built, open-source relativistic graphics engine allows the speed of light in the game to approach the player’s own maximum walking speed. Visual effects of special relativity gradually become apparent to the player, increasing the challenge of gameplay. These effects, rendered in realtime to vertex accuracy, include the Doppler effect; the searchlight effect; time dilation; Lorentz transformation; and the runtime effect.

A production of the MIT Game Lab.

Play now for Mac and PC! http://gamelab.mit.edu/games/a-slower-speed-of-light/

PermalinkCommentsscience game video-game mit 3d light-speed

 “The disc itself is about 5 inches in diameter. It can record...

2012 Oct 1, 8:21


 “The disc itself is about 5 inches in diameter. It can record one hour of stereo music on one side — and it is only a one-sided disc, it’s not meant to be played on two sides…”

Sony demos the CD at TED in 1984 (by TEDBlogVideo)

PermalinkCommentsvideo cd ted music

DSL modem hack used to infect millions with banking fraud malware | Ars Technica

2012 Oct 1, 6:33

According to the links within this article, although the root URI of the router requires authentication, the /password.cgi URI doesn’t and the resulting returned HTML contains (but does not display) the plaintext of the password, as well as an HTML FORM to modify the password that is exploitable by CSRF.

The attack… infected more than 4.5 million DSL modems… The CSRF (cross-site request forgery) vulnerability allowed attackers to use a simple script to steal passwords required to remotely log in to and control the devices. The attackers then configured the modems to use malicious domain name system servers that caused users trying to visit popular websites to instead connect to booby-trapped imposter sites.

PermalinkCommentstechnical security html router web dns csrf

Ben Goldacre’s TED talk on publication bias, drug...

2012 Sep 28, 3:55


drug companies hiding the results of clinical trials.

(via I did a new talk at TED, on drug companies and hidden data.)

PermalinkCommentsscience video ted
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