maxogden/voxel-engine — pull request #64 by bmeck (2013-03-13 14:50:31+00:00)
Title: Fix right mouse button detection for state.firealt

See:

http://www.quirksmode.org/js/events_properties.html#button

IE is just broken around this (and .button) and will need fixing in kb-controls upstream:

http://msdn.microsoft.com/en-us/library/ie/ff974884(v=vs.85).aspx