Re: [pointerevents] pointerup pressure should always be 0

> On Sep 21, 2016, at 7:31 AM, Mustaq Ahmed via GitHub <sysbot+gh@w3.org> wrote:
> 
> The definition of pressure in the spec seems to have another crack 
> here: 
> 
>> For hardware that does not support pressure, the value must be 0.5 
> when in the active buttons state and 0 otherwise.
> 
> So in this case, a hovering barrel button press on a stylus would 
> report a pressure of 0.5, which seems counter-intuitive. Same is true 
> for a stylus that is flipped to eraser mode, see #134.
> 
> So instead of adding a Note, I prefer fixing the definition .
> 

I would recommend that a stylus without pressure should report 1.0 not 0.5. The thinking goes like this:

In an application I choose a line width. If I draw with a mouse this is the width that will be drawn.

With a pressure stylus I will draw a percentage of that width (assuming pressure modulates width not opacity or some other characteristic) up to full pressure = full width.

A non-pressure stylus should act like a mouse and draw full width, not 50% with a non-pressure stylus, up to 100% with a pressure stylus, and 100% with a mouse.

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A good scapegoat is nearly as welcome as a solution to the problem.

Received on Wednesday, 21 September 2016 17:14:13 UTC