Question about wheel events

The current Editor's Draft has this description of the deltaMode 
property of WheelEvent

> deltaMode of type unsigned long, readonly
>     The deltaMode attribute contains an indication of to indicate the units of measurement for the delta values. The default value is DOM_DELTA_PIXEL (pixels). The value of deltaMode may be different for each of deltaX, deltaY, and deltaZ, based on system configuration.

Does the fact that deltaMode can be different for the X, Y, and Z axes 
mean that browsers always generate separate events for each axis?

If a user moves the mouse wheel "diagonally" to scroll down and to the 
right, is the browser required to generate one wheel event, two wheel 
events, or can it do either one of those things?

I think the spec ought to be clarified to explain this.

	David Flanagan

Received on Wednesday, 13 October 2010 23:33:10 UTC