The green ball moves back and forth on the X axis...between -4 and +4 randomly at any one moment. That movement determines which note is played by the instrument. The X movement is also captured by a variable which is used to produce the up and down (Y) movement of a blue dot as it crosses the screen. So you can track the random sounds produced by the green ball. If you do things this way you could track practically anything...even the wild dances of the Scratch Cat. Hope you enjoy watching this! --Larry828
