#include <windows.h>
DWORD SetMapperFlags
	HDC32 hDC,
	DWORD dwFlag


extract from
 Windows Font Mapping

 Ron Gery

 Microsoft Developer Network Technology Group

 Created: June 8, 1992

An application can, to some extent, filter which physical fonts are examined by the font mapper. Aspect-ratio filtering, which is available in both Windows versions 3.0 and 3.1, allows an application to specify that only fonts designed for the device's aspect ratio should be considered by the font mapper. An application enables and disables this filter by using the SetMapperFlags function. Because nonscaling raster fonts are designed with a certain aspect ratio in mind, it is sometimes desirable to ensure that only fonts actually designed for the device are used. When this filter is enabled, the font mapper does not consider any physical fonts whose design aspect ratio does not match that of the device. Aspect-ratio filtering does not affect TrueType fonts because they can scale to match any aspect ratio. This filter affects all font selections to the DC until the filter is turned off. Aspect-ratio filtering is a holdover from earlier times and is not a recommended approach in today's font world.