W3C unveils the Touch Events Specification. It’s a rough draft, I guess — it doesn’t even have an official URL on www.w3.org yet. But I like it a lot.
Editor Doug Schepers did the sensible thing and started with Apple’s specification (see the index), to which he added, to my delight, a fair number of properties I suggested:
radiusX/Y for the touch’s radius,
force to measure the touch’s force, and touchenter and touchleave events that we are going to need badly in the future.
A few remarks:
shiftKeyshould be removed. They don’t make sense in a touchscreen context. True, Apple defines altKey (though not ctrlKey and shiftKey, oddly), but I have no clue what the Alt key is on iOS, and it likely won’t exist on any future touchscreen device, either.
radiusX/Y? Pixels, of course. All other X/Y properties use them as units.
forceis going to be an interesting issue. The spec defines an unitless value of 0 to 1, but what exactly does 1 mean? Full force, probably, but how do we define full force? The maximum pressure the device can measure, probably.
Does iOS implement it like that? The other browsers don’t — that’s for sure.
[...] when the user places a more touch points on the touch surface than the device or implementation is configured to store, in which case the earliest touch point in the list must be removed.
But these are minor points at best. All in all this is an excellent first step towards the specification of touch events.
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