Sierpinski triangle - 140byt.es

annotated.js

function(){
  /* Rules:                      // make sure
  (1) anonymous function         // to annotate
  (2) optionally self-executing  // your code
  (3) <140 bytes                 // so everyone
  (4) no global vars             // can learn
  (5) MIT license                // from it!
  (6) good luck!
*/}

index.js

function(){/*Rules: (1) anonymous function (2) optionally self-executing (3) <140 bytes (4) no global vars (5) MIT license (6) good luck!*/}

LICENSE.txt

Copyright (c) 2011 YOUR_NAME_HERE, YOUR_URL_HERE
 
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:
 
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
 
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

package.json

{
  "name": "sample",
  "keywords": [ "sample", "original" ]
}

9 bytes smaller:
function(c,s,i,a,b,r){for(a=b=0;i--;r=Math.random())c.fillRect(a=(r>2/3&&s)+a>>1,b=(r<1/3&&s)+b>>1,1,1)}

@williammalo
Results will be different though, because r will be undefined the first time the loop runs. This should work and be a byte smaller too:

``` function(c,s,i,a,b){for(a=b=0;i--;)r=Math.random(),c.fillRect(a=(r>2/3&&s)+a>>1,b=(r<1/3&&s)+b>>1,1,1)}``

@xpansive
"r" will leak to the global scope.

Also, 20 bytes smaller than the original:
function(c,s,i,a,b,r){for(;i--;r=Math.random()_3)c.fillRect(a=(r>2)_s+a>>1,b=(r<1)*s+b>>1,1,1)}

Whoops, totally missed that.

@williammalo
Thanks a lot for your improvements; I adjusted the code according to your last variant. Values "a" and "b" are now rounded each iteration (difference from my original version), but I suppose that is not a problem :-)

@ondra Thanks! :)
1 byte smaller!:
function(c,s,i,a,b,r){for(;i--;r=Math.random()_3)c.fillRect(a=(r>2)_s+a>>1,b=!~~r*s+b>>1,1,1)}