How to detect font scaling mode used?

In the Windows 7 "Custom DPI Setting" window, there is 开发者_如何学编程a setting called "Use Windows XP style DPI scaling". Does anyone know how to detect if this setting is in use?

Not sure if either of these will give you what you want but might be useful:

IsProcessDPIAware - Determines whether the current process is dots per inch (dpi) aware such that it adjusts the sizes of UI elements to compensate for the dpi setting.

Writing High-DPI Win32 Applications - Using the code in the Getting System Information section you could probably tell the difference in some way when the setting is on vs off.