The Windows port of GTK is an implementation of GDK (and therefore GTK) on top of the Win32 API. When compiling GTK on Windows, this backend is the default.

More information about GTK on Windows, including detailed build instructions, binary downloads, etc, can be found online.

## Windows-specific environment variables

The Win32 GDK backend can be influenced with some additional environment variables.

### GDK_IGNORE_WINTAB

If this variable is set, GTK doesn’t use the Wintab API for tablet support.

### GDK_USE_WINTAB

If this variable is set, GTK uses the Wintab API for tablet support. This is the default.

## Windows-specific handling of cursors

By default the “system” cursor theme is used. This makes GTK prefer cursors that Windows currently uses, falling back to Adwaita cursors and (as the last resort) built-in X cursors.

When any other cursor theme is used, GTK will prefer cursors from that theme, falling back to Windows cursors and built-in X cursors.

Theme can be changed by setting `gtk-cursor-theme-name` GTK setting. Users can override GTK settings in the `settings.ini` file or at runtime in the GTK Inspector.

Themes are loaded from normal Windows variants of the XDG locations: `HOME`%/icons/THEME/cursors`,`APPDATA`%/icons/THEME/cursors`, `RUNTIME_PREFIX/share/icons/THEME/cursors`

The `gtk-cursor-theme-size` setting is ignored, GTK will use the cursor size that Windows tells it to use.