Microsoft commemt on Pointer Gestures

[alliMSFT]

Implementable:

a. A app can break this SC, but I don't know how a web app can break this SC.

b. Exception is needed where the use of multiple fingers and complexity gestures are essential. Piano lesson is an example.

Clarity of text:

a. No definition of complex and simple pointer gestures. This lack of definition also makes the SC not testable and not implementable.

Helpful:

a. There is an implicit assumption of a single user here. But there could be scenarios where multiple users are interacting together and invalidate the spirit of the SC. Please draw up a boundary that this is applicable to singer user scenario.

[detlevhfischer]

For reference:

• This comment Microsoft commemt on Pointer Gestures #196 refers to issue #61 Pointer gestures. In the WCAG 2.1 draft, this is SC 2.5.4 Pointer Gestures

Draft definition of pointer gesture:
A pointer gesture interacts with a target on the screen by positioning a cursor or a pointer like the finger or a dedicated pen over the x/y coordinates of the target. The cursor is positioned over the target via a mouse, trackpad, joystick or by an eye-tracking or voice interface. On touch screens, the pointer (finger or pen) can directly touch the target.
Simple pointer gestures activate the target below the pointer by clicking or pushing a dedicated button or issuing some other established form of activation (such as blinking or a voice command). Complex pointer gestures require a sequence of movements such as touching, dragging and dropping, or in multi-touch interfaces, target touches with two or more fingers, like split tap gestures or pinch gestures.

a. A app can break this SC, but I don't know how a web app can break this SC.

While it is not yet common, authors can detect multiple touches in modern browsers and trigger functions based on multiple target touches or touch moves. See, for example, Multi-touch Web Development (already 6 years old) and an example that allows simultaneoaus dragging of two sliders Add touch to your site, demo 2 - (works on iOS 10.3, but not on Windows 10 laptop with touch screen - not yet tested on Android).

a. No definition of complex and simple pointer gestures. This lack of definition also makes the SC not testable and not implementable.

For now, the proposed definition takes only a single tap as 'simple gesture' and everything else: swipes and pans, long presses, double taps, split taps, etc., as 'complex gesture'. This distinction might need further discussion - where do gestures start becoming 'complex'?

[detlevhfischer]

A revised SC including the exceptions you suggested would be:

"Functionality requiring complex or timed pointer gestures or multi-pointer gestures can also be operated with simple pointer gestures unless the use of multiple fingers and complex gestures is essential or content is operated in a multi-user environment."

[awkawk]

@alexswli Thank you for the comment. An updated version of this SC is available at https://www.w3.org/TR/WCAG21/#pointer-gestures