servo library to move servo to newPostion over some time interval?

I wanted to have a set of servos move in a coordinated pattern over time; think of the dancing water jets in Las Vegas.

I ended up writing my own infrastructure. A key function is:

servoMoveToPosition ( newPosition, startTime, endTime)

newPosition is in degrees
startTime and endTime are both values that could be returned by millis()

My code figures out how far the servo has to move and how long it has to get there. Then I pulse the code every cycle through the main loop and the code decides where the servo should be right now and moves it if appropriate. This allows for some coordinated "dance" movements that automatically move at whatever speed is appropriate for the current time segment.

My question: has anyone written a class library to do this kind of thing? Rather than continuing to enhance my own code I'd prefer to build on something that already exists and maybe give back to the community.

You can see an example of this in action here: Shrimpware breadbox for the arduino and raspberry pi - YouTube