LOGFONT  18P6JVU 

The LOGFONT structure defines the attributes of a font.

typedef struct tagLOGFONT {  // lf

   LONG lfHeight;

   LONG lfWidth;

   LONG lfEscapement;

   LONG lfOrientation;

   LONG lfWeight;

   BYTE lfItalic;

   BYTE lfUnderline;

   BYTE lfStrikeOut;

   BYTE lfCharSet;

   BYTE lfOutPrecision;

   BYTE lfClipPrecision;

   BYTE lfQuality;

   BYTE lfPitchAndFamily;

   TCHAR lfFaceName[LF_FACESIZE];

} LOGFONT;

Members

lfHeight

Specifies the height, in logical units, of the font s character cell or character. The character height value (also known as the em height) is the character cell height value minus the internal-leading value. The font mapper interprets the value specified in lfHeight in the following manner:

For all height comparisons, the font mapper looks for the largest font that does not exceed the requested size.

This mapping occurs when the font is used for the first time.

For the MM_TEXT mapping mode, you can use the following formula to specify a height for a font with a given point size:

lfHeight = -MulDiv(PointSize, GetDeviceCaps(hDC, LOGPIXELSY), 72);

lfWidth

Specifies the average width, in logical units, of characters in the font. If lfWidth is zero, the aspect ratio of the device is matched against the digitization aspect ratio of the available fonts to find the closest match, determined by the absolute value of the difference.

lfEscapement

Specifies the angle, in tenths of degrees, between the escapement vector and the x-axis of the device. The escapement vector is parallel to the base line of a row of text.

Windows NT:

When the graphics mode is set to GM_ADVANCED, you can specify the escapement angle of the string independently of the orientation angle of the string s characters.

When the graphics mode is set to GM_COMPATIBLE, lfEscapement specifies both the escapement and orientation. You should set lfEscapement and lfOrientation to the same value.

Windows 95:

The lfEscapement member specifies both the escapement and orientation. You should set lfEscapement and lfOrientation to the same value.

lfOrientation

Specifies the angle, in tenths of degrees, between each character s base line and the x-axis of the device.

lfWeight

Specifies the weight of the font in the range 0 through 1000. For example, 400 is normal and 700 is bold. If this value is zero, a default weight is used.

The following values are defined for convenience:

lfItalic

Specifies an italic font if set to TRUE.

lfUnderline

Specifies an underlined font if set to TRUE.

lfStrikeOut

Specifies a strikeout font if set to TRUE.

lfCharSet

Specifies the character set. The following values are predefined:

ANSI_CHARSET
DEFAULT_CHARSET
SYMBOL_CHARSET
SHIFTJIS_CHARSET
GB2312_CHARSET
HANGEUL_CHARSET
CHINESEBIG5_CHARSET
OEM_CHARSET

Windows 95 only:

JOHAB_CHARSET
HEBREW_CHARSET
ARABIC_CHARSET
GREEK_CHARSET
TURKISH_CHARSET
THAI_CHARSET
EASTEUROPE_CHARSET
RUSSIAN_CHARSET
MAC_CHARSET
BALTIC_CHARSET

The OEM_CHARSET value specifies a character set that is operating-system dependent.

You can use the DEFAULT_CHARSET value to allow the name and size of a font to fully describe the logical font. If the specified font name does not exist, a font from any character set can be substituted for the specified font, so you should use DEFAULT_CHARSET sparingly to avoid unexpected results.

Fonts with other character sets may exist in the operating system. If an application uses a font with an unknown character set, it should not attempt to translate or interpret strings that are rendered with that font.

This parameter is important in the font mapping process. To ensure consistent results, specify a specific character set. If you specify a typeface name in the lfFaceName member, make sure that the lfCharSet value matches the character set of the typeface specified in lfFaceName.

lfOutPrecision

Specifies the output precision. The output precision defines how closely the output must match the requested font s height, width, character orientation, escapement, pitch, and font type. It can be one of the following values:

Applications can use the OUT_DEVICE_PRECIS, OUT_RASTER_PRECIS, and OUT_TT_PRECIS values to control how the font mapper chooses a font when the operating system contains more than one font with a given name. For example, if an operating system contains a font named Symbol in raster and TrueType form, specifying OUT_TT_PRECIS forces the font mapper to choose the TrueType version. Specifying OUT_TT_ONLY_PRECIS forces the font mapper to choose a TrueType font, even if it must substitute a TrueType font of another name.

lfClipPrecision

Specifies the clipping precision. The clipping precision defines how to clip characters that are partially outside the clipping region. It can be one or more of the following values:

lfQuality

Specifies the output quality. The output quality defines how carefully the graphics device interface (GDI) must attempt to match the logical-font attributes to those of an actual physical font. It can be one of the following values:

lfPitchAndFamily

Specifies the pitch and family of the font. The two low-order bits specify the pitch of the font and can be one of the following values:

DEFAULT_PITCH
FIXED_PITCH
VARIABLE_PITCH

Bits 4 through 7 of the member specify the font family and can be one of the following values:

FF_DECORATIVE
FF_DONTCARE
FF_MODERN
FF_ROMAN
FF_SCRIPT
FF_SWISS

The proper value can be obtained by using the Boolean OR operator to join one pitch constant with one family constant.

Font families describe the look of a font in a general way. They are intended for specifying fonts when the exact typeface desired is not available. The values for font families are as follows:

lfFaceName

A null-terminated string that specifies the typeface name of the font. The length of this string must not exceed 32 characters, including the null terminator. The EnumFontFamilies function can be used to enumerate the typeface names of all currently available fonts. If lfFaceName is an empty string, GDI uses the first font that matches the other specified attributes.

See Also