Using CTK+ on Windows: CTK+ 3 Reference Manual

## Using CTK+ on Windows Using CTK+ on Windows — Windows-specific aspects of using CTK+ |

## Using CTK+ on Windows

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

### Windows-specific commandline options

The Windows CDK backend can be influenced with some additional command line arguments.

`--sync`. Don't batch GDI requests. This might be a marginally useful option for debugging.

`--no-wintab`, `--ignore-wintab`. Don't use the Wintab API for tablet support.

`--use-wintab`. Use the Wintab API for tablet support. This is the default.

`--max-colors `number``. In 256 color mode, restrict the size of the color palette to the specified number of colors. This option is obsolete.

### Windows-specific environment variables

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

`CDK_IGNORE_WINTAB`. If this variable is set, CTK+ doesn't use the Wintab API for tablet support.

`CDK_USE_WINTAB`. If this variable is set, CTK+ uses the Wintab API for tablet support. This is the default.

`CDK_WIN32_MAX_COLORS`. Specifies the size of the color palette used in 256 color mode.

### Windows-specific handling of cursors

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

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

Theme can be changed by setting `ctk-cursor-theme-name` CTK+ setting. Users can override CTK+ settings in the `settings.ini` file or at runtime in the CTK+ 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 `ctk-cursor-theme-size` setting is ignored, CTK will use the cursor size that Windows tells it to use.

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