RE: Clarification of event generation with respect to touch-action

You're absolutely right.  The intended design is that you only care about the value of touch-action on the target element of the pointerdown event. After that, it doesn't matter what the value of touch-action is on elements you drag over.

Additionally, I think it should be clarified that the value of touch-action is checked prior to dispatching pointerdown (e.g. modifications to touch-action during the event won't be honored for that pointer). This, of course, is fundamental to ensure the performance optimizations for threaded scrolling that touch-action is intended to enable.

I opened bug 20311 for this: https://www.w3.org/Bugs/Public/show_bug.cgi?id=20311

-Jacob

From: Daniel Freedman [mailto:dfreedm@google.com]
Sent: Friday, December 7, 2012 2:34 PM
To: public-pointer-events@w3.org
Subject: Clarification of event generation with respect to touch-action

In section 6.1, the description of "none" for touch-action states that touches that begin on those elements will not perform default actions.
However, it is not stated if events may still be generated after the touch leaves that element with touch-action: none.

In the MSPointerEvent implementation, further MSPointerMoves are dispatched to elements that can have touch-action: auto or touch-action: inherit. Is this what is expected for PointerEvents as well? Can this be made more explicit?

Thanks!