Re: [PATCH 0/2] HID: huion: add libinput support

From: Nikolai Kondrashov
Date: Sun Feb 22 2015 - 07:34:03 EST

On 02/20/2015 07:34 AM, Peter Hutterer wrote:
On Thu, Feb 19, 2015 at 01:54:17PM +0200, Nikolai Kondrashov wrote:
Last, I think we could add these tablets in the libwacom project, so that there
will be a nice GUI to configure the buttons.

That would be a very welcome change, without doubt, thank you.

However, I can't help wondering, would it be more productive to allow libwacom
to work with just any basic tablet, without the need to add each one to the

Actually, libwacom is not tight to Wacom devices at all (or should not
be). It is just a database of devices to add what the kernel doesn't or
can not provide. The things that are in the db are for example how the
buttons are physically mapped on the device, what is the actual layout
(one svg file), if there are LEDs attached to the tablet.

All this needs a fine per-device tuning. We can add a generic
Huion/UClogic tablet too, but having a specific per-device definition
allows to show the exact mapping of the buttons on the overlay when
setting the functions.

I agree, that's a nice feature. However, I think being able to configure all
the applicable Wacom driver features relatively comfortably, even if the
tablet on screen doesn't exactly match your tablet, is still a win, compared
to not being able to do it.

For the unknown tablets we can just draw abstract tablets, emphasising that
control locations on the screen don't map to the actual locations. For
example, have the tablet drawn like an exploded diagram: surface, buttons,
dials - all separate. Something like this:

Buttons: * * * * * * *
Dials: O O
Work area: +------------+
| |
| |
| |

I think the users will be able to figure out the mapping by experimentation.

While it's just about possible to keep an up-to-date database of Wacom
tablets, I don't think we'll ever be able to list all those generic tablets
out there. Meanwhile a lot of people are left in the cold of xsetwacom and

not a reason to give up, IMO. most of these generic tablets are relatively
simple, so adding a libwacom entry should be a matter of minutes.
we'll never get full support of everything, but perfect is the enemy of good

Hmm, I see having all the tablets listed in the database as perfect and having
generic tablet handling as more practical, i.e. the other way around.

It might be easy for us to add a tablet entry, but not for the general user.
They will need to figure out they need to add that entry first and they'll
need to figure out what to put there and how. This will need to go through us
in the end and we'll need to extract all the information from the user, which
will likely require several e-mails for *each* tablet.

Meanwhile most users just want to draw.

I might be misunderstanding something, though.

Regardless, Benjamin work is making it all better, I cannot complain :)

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