wintab-adapter

This makes WinTab drivers usable from OTD-IPC v2 applications, such as future versions of OpenKneeboard. There is opt-in support for OTD-IPC v1, including OpenKneeboard v1.

It also works around several common driver bugs:

• Broken or missing support for non-foreground windows (WTOverlap() and WT_OVERLAP)
• Incomplete or buggy support for axis scaling and unit mapping via the lcOut fields
• Missing or buggy support for setting the Y axis orientation

What doesn't it do?

It is able to work around some bugs in the drivers, but it's not able to add completely missing features.

Driver	Correct tablet area	Pen buttons	Tablet buttons
Wacom v6.4.12	✅	❌	❌
Huion v15.7.6	❌	❌	❌
Huion "3ExpressKey_0Softkey"	❌	🐛	❌
Gaomon v14.8.133	❌	❌	❌
XP-Pen v4.0.12	❌	❌	❌
Wacom v6.4.5	✅	✅	✅
OpenTabletDriver	✅	✅	✅

❌: indicates a limitation imposed by the manufacturer's driver, not this adapter.

🐛: indicates the driver provides this feature, but it is unreliable

These versions are the latest as of 2026-01-07

Huion "3ExpressKey_0SoftKey" is a driver published in 2018, and is still the latest available for some tablets such as the Huion H420, a.k.a. '420 OSU'.

I need those features!

These features are usable with this adapter when they are made available by the hardware driver; only the driver manufacturer can add support for them on your tablet.

Your options are:

• Use OpenTabletDriver instead; strongly recommended
• Try older versions of your manufacturer's driver
  • For Wacom specifically, if your tablet is supported by v6.4.5, use that instead; Wacom informed me that WinTab control of buttons was intentionally removed in later versions
• You can ask your tablet manufacturer to implement OTD-IPC v2 so you can use their driver without this adapter
• You can ask your tablet manufacturer to add the missing features to their WinTab driver

How do I use this?

DON'T.; use OpenTabletDriver instead if at all possible.

That said, you can download the latest version from releases (you don't need the debug symbols), then:

• Wacom:
  • Run wintab-adapter-64.exe
  • Administrator is not required
  • If your driver has these options, set all pen and expresskey buttons to 'Application Defined'
  • If not, you may want to set them to 'disabled' so you don't accidentally trigger other actions
• Huion:
  • Try both:
    • wintab-adapter-64.exe --hijack-buggy-driver=Huion (for most tablets)
    • wintab-adapter-64.exe --hijack-buggy-driver=HuionAlternate (for some older models)
  • Administrator sometimes required:
    • The Huion driver is inconsistent about whether it runs elevated
    • If the Huion driver is running elevated, you must run wintab-adapter-64.exe elevated
    • Otherwise, either way works
  • Set the screen mapping to 'All Display'
    • in some versions of the driver, this is labeled as 'All desktop area'
  • You may want to set pen and button bindings to 'disabled' so you don't accidentally trigger other actions
    • in some versions of the driver, this is labeled as 'none'
  • Turn off rotation
• Gaomon:
  • Run wintab-adapter-32.exe --hijack-buggy-driver=Gaomon
  • Administrator always required
  • Set the screen mapping to 'All Display'
  • You may want to set pen and button bindings to 'disabled' so you don't accidentally trigger other actions
  • Turn off rotation
• XP-Pen:
  • Run wintab-adapter-32.exe --hijack-buggy-driver=XPPen
  • Administrator is not required
  • Set the screen mapping to 'All Monitor' and "Set full screen"
  • Turn off rotation
• All others: Try wintab-adapter-64.exe without any options; this will work with any correctly implemented WinTab driver. If this doesn't work, your options are:
  • Try all the options above for other manufacturers; many tablet brands are just different names for the same manufacturer
  • Use OpenTabletDriver
  • Contact your manufacturer and ask them to fix their WinTab driver

Using with OpenKneeboard v1

• run the adapter with --otd-ipc-v1 in addition to any other options you need (see above)
• in OpenKneeboard Settings → Input, configure OpenKneeboard to use OpenTabletDriver instead of WinTab, as this adapter pretends to be OpenTabletDriver

It is likely that no buttons will work due to missing features in vendor drivers, so you will be unable to erase or bind anything; however, the pen tip should work.

What does --hijack-buggy-driver do?

It works around buggy or incomplete implementations of WTOverlap() and WT_OVERLAP, allowing the adapter to work when it is not the foreground window.

If you're familiar with OpenKneeboard's "invasive" mode, this solves the same problem by doing roughly the opposite:

• 'invasive' mode modifies other programs (e.g. games) so that when they are in the foreground, they load the tablet driver and forward the data to OpenKneeboard
• wintab-adapter instead modifies the driver so that it never realizes that other programs (like the games) are in the foreground

These drivers repeatedly ask Windows what the foreground Window is, and/or the Window under the mouse cursor is. On my system, this happens between 700 and 1500 times per second.

The --hijack-buggy-driver option intercepts the following calls so that the driver always thinks that the wintab-adapter window is the foreground window:

• GetForegroundWindow()
• WindowFromPoint()

This has the advantages that:

• it's simpler
• anti-cheat is less likely to have issues with it
• buggy drivers are much less likely to crash other apps (games)