
Xkcd's mindboggling April Fools comic - dkulchenko
http://www.reddit.com/r/comics/comments/rnpiw/mindboggling_xkcd_april_fools_comic/
======
dkulchenko
I fired up Chrome's dev tools to figure out how it works. 

The JS that's doing the work is at <http://imgs.xkcd.com/static/waldo.js>.  On
page load, it sends a GET request to
<http://umwelt.xkcd.com/story/ghenkEggov8> with params w for the browser width
in pixels, h for the height and r with the referrer.  The rest of the
qualifiers (geoloc and browser (user-agent)) can be determined on the server-
side. 

As a response, you get back JSON with the alt-text, image URL, and positioning
info, which is then used to fetch and position the image. 

Fun fact: the server-side is written in Haskell:

    
    
      $ wget -S http://umwelt.xkcd.com/story/ghenkEggov8
      --2012-04-01 11:26:41--      http://umwelt.xkcd.com/story/ghenkEggov8
      Resolving umwelt.xkcd.com... 208.118.225.100
      Connecting to umwelt.xkcd.com|208.118.225.100|:80...  connected. 
      HTTP request sent, awaiting response... 
        HTTP/1.1 200 OK
        Server: Warp/1.1.0.1
        Content-Type: application/javascript
        Access-Control-Allow-Origin: *
        Transfer-Encoding: chunked
        Connection: close
    

<http://hackage.haskell.org/package/warp/>

Well done Randall and davean. 

------
rauljara
The thread on xkcd forums has screenshots of a lot of the different comics. 
It's crazy how many variations there are.  The one in hebrew (for those in
Israel) makes me think people will be finding new ones for quite a while. 

[http://forums.xkcd.com/viewtopic.php?f=7&t=82442&sta...](http://forums.xkcd.com/viewtopic.php?f=7&t=82442&start=1)

------
sumukh1
Here's a direct link for anyone who hasn't seen the comic yet.  Try it on your
mobile network and on different browsers

Valid for today: <http://xkcd.com/>

~~~
the_imp
At least from Finland and using Chrome, following the above leads me to this
version, which I've not seen noted elsewhere -- is it specific to Hacker News? 

[http://imgs.xkcd.com/a1panels/4444e5d258b5f12b41350ed2c550e3...](http://imgs.xkcd.com/a1panels/4444e5d258b5f12b41350ed2c550e32501eb4269412603a0a250123d211d29e3.png)

~~~
jonah
I see the same in California on Chrome and Firefox when coming from HN. 

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micheljansen
The amount of preparation work that must have gone into this is admirable. 
There are so many variations! 

------
tristan_louis
It's quite an impressive effort.  Works on user-agent, referer, or geolocation
(or possibly a mix)

~~~
morsch
Also, browser window width. 

------
ConstantineXVI
I hit it from one of our EC2 boxen and got this:
[https://skitch.com/constantinexvi/8q5k9/skitched-20120401-14...](https://skitch.com/constantinexvi/8q5k9/skitched-20120401-145317)

And oddly, got the Jersey comic from my Dallas-based Linode
<https://skitch.com/constantinexvi/8q5m2/xkcd-umwelt-chromium>

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protomyth
Tried Opera and Safari on the Mac and got a broken plugin graphic with "There
does not exist - nor could their ever exist - a plugin capable of displaying
this content"

alt text is "Umwelt is the idea that because their senses pick up on different
things, different animals in the same ecosystem actually inhabit very
different worlds." 

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mtrimpe
Reddit seems to have a near complete overview already:
[http://www.reddit.com/r/comics/comments/rnpiw/mindboggling_x...](http://www.reddit.com/r/comics/comments/rnpiw/mindboggling_xkcd_april_fools_comic/)

My favorite most definitely is the military one:
[http://imgs.xkcd.com/a1panels/961f9f87076b08c0d29f9182d6e1b3...](http://imgs.xkcd.com/a1panels/961f9f87076b08c0d29f9182d6e1b370a059ddc1f4bacc246bb850fdcb174e44.png)

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kd0amg
I got the snake one, which changes as I resize the browser window.  I was
pleased to see somewhere along the snake was the elephant it had eaten. 

~~~
numlocked
I started ready The Little Prince earlier this morning for the first time.  The
snake + elephant were in the first version of the comic that I saw.  My mind
was surely the most boggled of any visitor. 

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instakill
Surprised there's no Wikipedia addition to Umwelt after today's xkcd.  Or maybe
there is but I just don't see it. 

~~~
Dylanlacey
I See (Or perhaps a different sense) what you did there. 

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srl
This guy's dedication continues to astound me. 

Apparently he's still changing things - people who complain on the forum
thread have noticed a few hours later that relevant fixed have been made. 

(Also, I wonder how much was done by rpm and how much by davean.) 

------
morsch
It's fantastic, and I enjoyed the different combinations.  But I don't really
_get_ the one I get, the white disk on black thing.  White light at the end of
the tunnel?  The alt-text doesn't really help me, either. 

~~~
blahedo
Yeah, that's the only one I can get too, with either of my regular browsers
and no matter who the referrer is.  No clue. 

~~~
hosh
Probably the default. 

------
hosh
This should be an exhibit in a museum of modern art. 

It gives people a taste of the "post-PC" world we are evolving towards.  And
there are some deeper stuff, too. 

~~~
daemin
I would certainly count this as a great piece of art, not modern, not post-
modern, just current. 

Well done XKCD guys (and gals). 

------
karlbunch
LOL I'm using gogo inflight and it gave me a comic about Chicago.. Seems a
couple dynamic frames or static based on geoip? 

~~~
karlbunch
View source you can see each panel is a different frame and a little note in
the source:

title="Umwelt is the idea that because their senses pick up on different
things, different animals in the same ecosystem actually live in very
different worlds.  Everything about you shapes the world you inhabit--from your
ideology to your glasses prescription to your web browser." 

~~~
sliverstorm
Also known as the mouse-over text

------
bicknergseng
Is the IE9 version supposed to be a light at the end of a tunnel? 

~~~
rabidsnail
Safari seems to get the same thing, so probably not.  When I saw it the phrase
that came to mind was "cosmic sphincter".