What is the difference between Full Windows Touch Support and Limited Touch Support?


In the System control panel and in the PC Info section of the PC & Devices section of PC Settings, your device's pen and touch support can be reported in a variety of ways. Here is the matrix:

No pen Pen
No touch No Pen or Touch Input Pen Support
Single touch Single Touch Support Pen and Single Touch Support
Limited multi-touch Limited Touch Support with N Touch Points Pen and Limited Touch Support with N Touch Points
Full multi-touch Full Touch Support with N Touch Points Pen and Full Touch Support with N Touch Points

The meaning of No touch and Single touch are clear, but if a device supports multiple touch points, what makes the system report it as having Limited versus Full touch support?

A device with Full touch support is one that has passed Touch Hardware Quality Assurance (THQA). You can read about the Windows Touch Test Lab (WTTL) to see some of the requirements for full touch support.

If you have a touch device without full touch support, then Windows will lower its expectations from the device. For example, it will not use the timestamps on the device packets, and it will increase the tolerances for edge gestures.

Note that if test signing is enabled, then all multitouch drivers are treated as having full touch support. (This lets you test your driver in Full mode before submitting it to THQA.)

Comments (19)
  1. Brian_EE says:

    If your system doesn't have touchpad settings in Control Panel (like my Win7 Enterprise machine), you can access it by using Start->Run with "rundll32.exe shell32.dll,Control_RunDLL tabletpc.cpl" command line.

  2. kinokijuf says:

    Why does a touch keyboard button show up on my taskbar whenever i RDP into my machine?

  3. Myria says:

    With normal WHQL certification, users can bypass the feature by just clicking Yes at the dialog box.  This doesn't sound user-bypassable.  Love how Microsoft's extorting hardware developers here.

    [Are you claiming that the hardware certification lab is a profit center? -Raymond]
  4. @Myria: They kind of brought it upon themselves.  Remember the old days when drivers were so riddled with bugs that you'd be lucky to have a machine last for over a couple of weeks without running into some kind of issue?  And even now there are some companies that still have a hard time making decent code; I have yet to use a non-Apple laptop with a decent trackpad.

  5. Wear says:

    @Myria There's nothing to bypass. From the sounds of things if it hasn't been tested it'll still work fine. Windows will just use a 39 and a half inch pole to poke it just in case it explodes.

  6. 12BitSlab says:

    @ Brian EE -- thanks!

  7. alegr1 says:

    >And even now there are some companies that still have a hard time making decent code

    That includes Microsoft Hardware division. Their intellimouse software doesn't work well with the rest of Windows, and MS BlueTooth mouse just won't stay paired.

  8. Roger says:

    @Myria - I wish MSFT was like Apple.  Apple would never even allow the option to be anything but the best there (limited... smh). So what do we get in return? Absolute crap track-pads from Lenovo and such...

  9. Joshua says:

    [Are you claiming that the hardware certification lab is a profit center? -Raymond]

    No, he's claiming they're requiring the development to include an unnecessary expense. Given the garbage quality of non-WHQL drivers that aren't open source I'm not so sure.

    [Unnecessary expense is not the same as extortion. -Raymond]
  10. morlamweb says:

    @Myria: I take issue with the word "extortion".  Developers of multi-touch screens aren't prevented from running on Windows at all; it sounds like they run with reduced touch precision and/or functionality.  If hardware devs want full touch fidelity, then they have to prove that their devices will work in those conditions.

  11. foo says:

    @Brian_EE "start tabletpc.cpl" also works from the command line (at least on my machine). Less typing :)

  12. Myria says:

    It's exactly that: How would open-source drivers for some open hardware project manage full functionality?  I don't know how they'd even be able to join SysDev just to submit the drivers at all...

  13. Joshua says:

    @Myria: Open source drivers almost always mean turning on test mode. (Insert political debate here if you wish).

  14. cheong00 says:

    @alegr1: I don't know. My Arc Mouse uses Bluetooth and it works well with my Surface Pro 3. Maybe they're doing better with recent hardware?

  15. GWO says:

    @Roger: So your claim is that only allowing expensive high quality hardware is preferable to allowing consumers to make their own trade off between price point and quality?

    There's a reason that a Windows 8.1 laptop can be purchased for $200 and a Macbook costs 4-5 times that much.

    [The difference between Limited and Full touch support has to do with the tolerances the system allows. It's okay to run a high quality touch screen in Limited mode. It just means that the system demands less from it. Maybe I should have said "Full touch support means that the system does not apply certain compatibility behaviors." -Raymond]
  16. ender says:

    > Open source drivers almost always mean turning on test mode. (Insert political debate here if you wish).

    Most open-source drivers are signed nowadays.

  17. Muzer_ says:

    @MNGoldenEagle: That's funny, because I'm yet to use an Apple laptop with a decent trackpad. They just appear to be totally unusable to most people I know, yet Apple users seem to be able to use them fine. So maybe it's all subjective; what you're used to.

  18. ender says:

    @Muzer_: same here - I bring my own mouse with me when I have to work with macbooks. Of course, many PC trackpads suck even more (ever used a HP Envy? Somebody thought that making the trackpad surface like sandpaper was a good idea).

  19. Entegy says:

    I've always had an idle curiosity about that, thanks!

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