mrdoob/three.js — pull request #4206 by jasongrout (2013-12-12 10:48:15+00:00)
Title: Change trackball mousewheel event to use a cross-browser version.

This uses Mozilla's cross-browser code at https://developer.mozilla.org/en-US/docs/Web/Reference/Events/wheel?redirectlocale=en-US&redirectslug=DOM%2FMozilla_event_reference%2Fwheel

Before this change, firefox would scroll the page while zooming, for example.