Press play in the bottom left to have it go, and scrub numbers/colors to your hearts content!

Part of the reason it slows down in livecoding is because of the way the original code uses setInterval, and every change reevaluates the code which polutes the scope and starts way too many threads going. I've added optional functionality to Tributary which gives you a run loop (using requestAnimationFrame) that doesn't polute anything.

Hope this helps!

    for ( var i = 1; i < 16; i++) {
        var br = 255 - ((Math.random() * 96) | 0);
        for ( var y = 0; y < 16 * 3; y++) {
            for ( var x = 0; x < 16; x++) {

                ...

            }
        }
    }

My interpretation of Bret's idea is that it would be better to have the ability to highlight the section of the texture being written by each section of the loop. It's not the sliders & live editing that are most important it's about linking abstract control into meaning within the learner.

the problem is from calling setInterval every time the code is evaluated, leading to way too many function calls/second