Re: [pointerevents] Stylus eraser: should it be a new pointerType instead of a button state?


> On Aug 27, 2016, at 4:49 AM, Patrick H.Lauke via GitHub <sysbot+gh@w3.org> wrote:
> 
> So if I understand the current situation correctly: in Windows/Edge, 
> erasing has been implemented/forced as a modifier key that's tied 
> specifically to pressure on the digitizer (in the case of the Surface 
> Pen, pressing eraser button while hovering has no effect, and it only 
> acts as modifier once the tip touches the screen; in the case of the 
> Wacom stylus, having the stylus flipped - which at low level is 
> distinguished as being an erased mode switch - has no effect, and the 
> hovering eraser is treated exactly the same as a hovering writing tip,
> and only once the eraser has any pressure it's translated into a pen 
> action with eraser modifier).

Backing up a bit.
At the hardware HID protocol level there’s three bits of interest here:
Invert = pen inverted or erase button depressed
Tip = pressure on tip but no Invert
Erase = pressure on tip while Inverted

What the system does with these:
Tip -> left click
Erase -> left click
Invert ->  (sorry, this list is incomplete)
 Mac: pointerType = Eraser
 Windows Wintab: cursor number = 2 and orientation = -90 degrees and TPS_INVERT is set in pkStatus
 Windows: PointerPoint Properties IsEraser or IsInverted
 X11: erase device send events

> The question for me is: are Microsoft likely to change the model and 
> treat the eraser button not as a modifier, but as a means of switching
> into "eraser mode", changing the `pointerType` to something new like 
> `eraser`? Or will PE somehow have to cater for both models (eraser as 
> modifier vs eraser as its own tool/type)?

“eraser mode” is a “modifier” as opposed to an action.

This behavior is ages old and highly unlikely to change.

I think the suggestion of having an eraser pointer type caters to both models.

I’ll be off the grid for the next week and a half so sorry if I don’t follow up.

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"Success is the ability to go from one failure to another with no loss of enthusiasm." - Sir Winston Churchill

Received on Sunday, 28 August 2016 03:54:23 UTC