Random Checkers

This adds a few more features to the last movie, and enables you to interact with it a bit. The symmetry, and some other drawing effects can be turned on and off by pressing the buttons.

Note: Many of the movies in my collection have buttons or sliders which allow you to control certain features. For any sufficiently complex animation, there may be many features that may be controlled in this manner, but I will usually choose just a few for user-control, in order to keep the interface relatively simple. The code for the buttons and sliders is at the bottom of the script, and can be removed without affecting the rest of the movie.

Up till now, I've computed a random color using the following line:

var tint = Math.floor(Math.random()*0x1000000);

var t = getTimer()*.001;
var r = 128+Math.sin(t)*127;
var g = 128+Math.sin(t + saturation*kDegrees120)*127;
var b = 128+Math.sin(t + saturation*kDegrees240)*127;
var tint = (r << 16) | (g << 8) | b;

Also, I've added add the following code to produce a checkerboard pattern.

if ((x + y) & 1) // Checkboard test
   tint |= 0x808080; // lighten pixel
else
   tint &= 0x7F7F7F; // darken pixel

UPDATE: The source code below now contains an Actionscript 3 version, in addition to the original Flash MX code.