Add Wacom touch support

[AbstractQbit]

I have only tested this with cth-470, pth-850 and pth-860;
8th and 9th gen consumer tablets need testing before merging this.

Also fixes #935.

[InfinityGhost]

What is this function for?

[AbstractQbit]

Newtonsoft refused to serialize that property without this

[InfinityGhost]

Wouldn't JsonPropertyAttribute suffice for this? I've never seen this needed before.

[InfinityGhost]

After discussion, we should at least add xmldocs explaining what this is used for.

[X9VoiD]

WacomTouchReport and IntuosV3Report is wacom_bpt3_touch()

WacomTouchReport is applicable only to endpoints of length 64

This parser is used for devices of these types

Intuos 5 Lineup	Intuos P Lineup	Intuos HT Lineup	Bamboo Lineup
Intuos5	IntuosPS	IntuosHT	Bamboo Pen
Intuos5S	IntuosPM	IntuosHT2	Bamboo Touch
Intuos5L	IntuosPL		BambooPT

So with that said, we can determine that these devices that the PR modified are to be verified working:

BambooPT	IntuosHT	IntuosHT2	Intuos5	Intuos5L	IntuosPS	IntuosPM
CTH-470	CTH-480	CTH-490	PTH-650	PTH-850	PTH-451	PTH-651
CTH-670	CTH-680	CTH-690
	CTL-480	CTL-490
	CTL-680	CTL-690

PTH-660 however is a device that cannot be verified, there are references to it in input-wacom, but no full configuration for it. (doesn't specify parser, size, max touch points, etc, as if it's unsupported)

[AbstractQbit]

Here are the touch dimensions for PTH-460/660/860:
https://github.com/linuxwacom/input-wacom/blob/74f6fd70f2584f0548303583ef8713e53d3314a5/4.5/wacom_wac.c#L3793-L3816

[X9VoiD]

The thing is that the kernel module did not declare PTH-660 (PID: 855 or 0x357) as a supported device so I can't verify that one.

[InfinityGhost]

Man I sure do love CI

[InfinityGhost]

Is this ready for merge?

[ocumo]

Sorry for posting in this old thread, but something is not clear, and before I create or pollute other threads, just a question:
Does this includes Wacom PTH-851?
With PTH-851, touch is detected in the tablet debugger, but not by any other program or desktop.
The other things work OK in all modes.
Should I make a separate request to add touch support for PTH-851?
Thanks!
(Linux, Xubuntu 22.04 LTS)

[jamesbt365]

This pull request parses touch. OTD does not support any touch output at this time.

[ocumo]

Thanks.
So, that means, that for now OTD reads the input --correctly, as far as I can see-- but it won't output it to any program, right?
Is touch output a thing that might ever be supported in the future, even for a limited number of tablets, or is it completely out of the scope of the project? I can only guess that getting to parse the touch is a good clue that touch is planned or at least desired.
Thanks again

[jamesbt365]

See #1664.

[ocumo]

Ok, I am going to have to guess that you mean "maybe in the future some limited functionality could happen; but it may take years". Did I guess right?

Please I don't want to keep trying to guess an statement. If I said something inappropriate, please say so. Otherwise, please could you pass this to a colleague who could provide a simple, friendly "Yes, exactly" or "No, you are wrong, ..." kind of statement. This is not a complex question and doesn't deserve so many posts. Thank you.

[jamesbt365]

#1664 is the issue tracking touch support. Touch is parsed on most tablets that support, meaning that OTD understands what touch is, but currently has no support for actually outputting this to the display. The issue that I linked is the issue tracking this.

We are a small team, we are not paid to develop this project and therefore we do not have all the time in the world to work on specific features so unless anybody steps up outside of our team to supply any touch support before we do this is not in scope for 0.7 or potentially even 0.7.1 depending on what time we have available, hence why it is in the backlog milestone. For an overview on all the milestones see this.

We have no plans on implementing this right now as we have more important things to do like getting a stable codebase for 0.7 to release on. There is lots to do in that milestone so do you not expect this any time soon, we have limited resources here.

[ocumo]

Ok, thank you so very much!

I totally understand. I am by no means criticizing lack of support of any feature. Quite the contrary: I am glad that there is this project. The reason for my curiosity (not a request) is that I have only recently discovered OTD and dumped Wacom drivers to give it a chance, since there is no good GUI solution for tablets in Linux. I just need to understand the limitations to adapt and try to live with it. Touch would be nice, but I am with you, it's not top priority.

I will keep using OTD, and I have already had my quote of troubleshooting and issues, and learned a few things about it in the meantime. I have noticed the lack of resources to put in place an extensive documentation, and I sympathize. I have been writing a few procedures for me, to help me avoid troubles with the installation procedure on my various systems, which I have to say could be improved in your wiki, nothing fancy, just a couple of notes or steps would avoid so much pain for many people, as many others had the same troubles as I did.

Thanks again