windows: Update the docs for env vars

We've replaced some env vars with a new one.
Update the docs to match.

diff --git a/docs/reference/gtk/windows.md b/docs/reference/gtk/windows.md
index 886b99f42f96a55c4310f579168a774daa8c8c67..96fa5e6291db94212fb405f962037c0181bb5493 100644 (file)
--- a/docs/reference/gtk/windows.md
+++ b/docs/reference/gtk/windows.md
@@ -14,14 +14,19 @@ instructions, binary downloads, etc, can be found
 The Win32 GDK backend can be influenced with some additional environment
 variables.
 
-### GDK_IGNORE_WINTAB
+### GDK_WIN32_TABLET_INPUT_API
 
-If this variable is set, GTK doesn't use the Wintab API for tablet support.
+If this variable is set, it determines the API that GTK uses for tablet support.
+The possible values are:
 
-### GDK_USE_WINTAB
+`none`
+: Disables tablet support
 
-If this variable is set, GTK uses the Wintab API for tablet support.
-This is the default.
+`wintab`
+: Use the Wintab API
+
+`winpointer`
+: Use the Windows Pointer Input Stack API. This is the default.
 
 ## Windows-specific handling of cursors