In this project, I wrote two sketches. One for Arduino and one for Processing. I included the servo library for Arduino. Processing is sending mouse positions back to Arduino via Serial. The mouse positions are mapped to the rotation of two servos. The servos have a max rotation of 180 degrees each.
It's used to create a game where the player has to rest all the coloured balls in the holes of the tray by using the mouse to control the two servos. A graphical output from Processing showing the X and Y position cues the player with a visual representation of the position of the tray.