mootools/mootools-more — pull request #1169 by challet (2012-12-06 13:02:40+00:00)
Title: Adding a ratio option to Drag class

These changes will add an option ratio to the Drag class :
if set, it will add a constraint during drag, linking the x and y properties together.
It is designed to always lower one of the properties, in order to stick to the limit option.