sorollet.js README refresh + Firefox compatibility

Since Firefox now supports Web Audio by default, I decided to update all of sorollet.js‘s examples (the two of them) to work with the WebAudio standard AudioContext instead of just using webkitAudioContext. I also added screenshots, which makes it look nicer:

Listen, world

Drum machine

Since sorollet.js is basically an input/output module (you ask it for a number of samples, and it delivers), internally it is totally standards agnostic. The only things I needed to change were pretty much the way the AudioContext and the ScriptProcessor nodes were initialised.

If you need to port webkit- based audio stuff to standards based audio, you can have a look at the article I wrote for the Mozilla Hacks blog.

Funny thing: I found a bug where ScriptProcessor nodes get called even if they are not connected. I prepared a nice test case… only to find the bug was already reported (#916384) and a test case existed. Sigh.

BUT MINE IS COOLER (because it works on Chrome too, and that way you can compare implementations).