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LOGFONTW structure (wingdi.h)

The LOGFONT structure defines the attributes of a font.

Syntax

typedef struct tagLOGFONTW {
  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;
  WCHAR lfFaceName[LF_FACESIZE];
} LOGFONTW, *PLOGFONTW, *NPLOGFONTW, *LPLOGFONTW;

Members

lfHeight

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.

Value Meaning
> 0 The font mapper transforms this value into device units and matches it against the cell height of the available fonts.
0 The font mapper uses a default height value when it searches for a match.
< 0 The font mapper transforms this value into device units and matches its absolute value against the character height of the available fonts.
 

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 specified point size:


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

lfWidth

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

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.

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.

lfOrientation

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

lfWeight

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.

Value Weight
FW_DONTCARE 0
FW_THIN 100
FW_EXTRALIGHT 200
FW_ULTRALIGHT 200
FW_LIGHT 300
FW_NORMAL 400
FW_REGULAR 400
FW_MEDIUM 500
FW_SEMIBOLD 600
FW_DEMIBOLD 600
FW_BOLD 700
FW_EXTRABOLD 800
FW_ULTRABOLD 800
FW_HEAVY 900
FW_BLACK 900

lfItalic

An italic font if set to TRUE.

lfUnderline

An underlined font if set to TRUE.

lfStrikeOut

A strikeout font if set to TRUE.

lfCharSet

The character set. The following values are predefined:

  • ANSI_CHARSET
  • BALTIC_CHARSET
  • CHINESEBIG5_CHARSET
  • DEFAULT_CHARSET
  • EASTEUROPE_CHARSET
  • GB2312_CHARSET
  • GREEK_CHARSET
  • HANGUL_CHARSET
  • MAC_CHARSET
  • OEM_CHARSET
  • RUSSIAN_CHARSET
  • SHIFTJIS_CHARSET
  • SYMBOL_CHARSET
  • TURKISH_CHARSET
  • VIETNAMESE_CHARSET
Korean language edition of Windows:
  • JOHAB_CHARSET
Middle East language edition of Windows:
  • ARABIC_CHARSET
  • HEBREW_CHARSET
Thai language edition of Windows:
  • THAI_CHARSET
The OEM_CHARSET value specifies a character set that is operating-system dependent.

DEFAULT_CHARSET is set to a value based on the current system locale. For example, when the system locale is English (United States), it is set as ANSI_CHARSET.

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 when creating a font, do not specify OEM_CHARSET or DEFAULT_CHARSET. 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

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.

Value Meaning
OUT_CHARACTER_PRECIS Not used.
OUT_DEFAULT_PRECIS Specifies the default font mapper behavior.
OUT_DEVICE_PRECIS Instructs the font mapper to choose a Device font when the system contains multiple fonts with the same name.
OUT_OUTLINE_PRECIS This value instructs the font mapper to choose from TrueType and other outline-based fonts.
OUT_PS_ONLY_PRECIS Instructs the font mapper to choose from only PostScript fonts. If there are no PostScript fonts installed in the system, the font mapper returns to default behavior.
OUT_RASTER_PRECIS Instructs the font mapper to choose a raster font when the system contains multiple fonts with the same name.
OUT_STRING_PRECIS This value is not used by the font mapper, but it is returned when raster fonts are enumerated.
OUT_STROKE_PRECIS This value is not used by the font mapper, but it is returned when TrueType, other outline-based fonts, and vector fonts are enumerated.
OUT_TT_ONLY_PRECIS Instructs the font mapper to choose from only TrueType fonts. If there are no TrueType fonts installed in the system, the font mapper returns to default behavior.
OUT_TT_PRECIS Instructs the font mapper to choose a TrueType font when the system contains multiple fonts with the same name.
 

Applications can use the OUT_DEVICE_PRECIS, OUT_RASTER_PRECIS, OUT_TT_PRECIS, and OUT_PS_ONLY_PRECIS values to control how the font mapper chooses a font when the operating system contains more than one font with a specified 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

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.

For more information about the orientation of coordinate systems, see the description of the nOrientation parameter.

Value Meaning
CLIP_CHARACTER_PRECIS Not used.
CLIP_DEFAULT_PRECIS Specifies default clipping behavior.
CLIP_DFA_DISABLE Windows XP SP1: Turns off font association for the font. Note that this flag is not guaranteed to have any effect on any platform after Windows Server 2003.
CLIP_EMBEDDED You must specify this flag to use an embedded read-only font.
CLIP_LH_ANGLES When this value is used, the rotation for all fonts depends on whether the orientation of the coordinate system is left-handed or right-handed.If not used, device fonts always rotate counterclockwise, but the rotation of other fonts is dependent on the orientation of the coordinate system.
CLIP_MASK Not used.
CLIP_DFA_OVERRIDE Turns off font association for the font. This is identical to CLIP_DFA_DISABLE, but it can have problems in some situations; the recommended flag to use is CLIP_DFA_DISABLE.
CLIP_STROKE_PRECIS Not used by the font mapper, but is returned when raster, vector, or TrueType fonts are enumerated. For compatibility, this value is always returned when enumerating fonts.
CLIP_TT_ALWAYS Not used.

lfQuality

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.

Value Meaning
ANTIALIASED_QUALITY Font is always antialiased if the font supports it and the size of the font is not too small or too large.
CLEARTYPE_QUALITY If set, text is rendered (when possible) using ClearType antialiasing method. See Remarks for more information.
DEFAULT_QUALITY Appearance of the font does not matter.
DRAFT_QUALITY Appearance of the font is less important than when PROOF_QUALITY is used. For GDI raster fonts, scaling is enabled, which means that more font sizes are available, but the quality may be lower. Bold, italic, underline, and strikeout fonts are synthesized if necessary.
NONANTIALIASED_QUALITY Font is never antialiased.
PROOF_QUALITY Character quality of the font is more important than exact matching of the logical-font attributes. For GDI raster fonts, scaling is disabled and the font closest in size is chosen. Although the chosen font size may not be mapped exactly when PROOF_QUALITY is used, the quality of the font is high and there is no distortion of appearance. Bold, italic, underline, and strikeout fonts are synthesized if necessary.
 

If neither ANTIALIASED_QUALITY nor NONANTIALIASED_QUALITY is selected, the font is antialiased only if the user chooses smooth screen fonts in Control Panel.

lfPitchAndFamily

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 bitwise 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.

Value Meaning
FF_DECORATIVE Novelty fonts. Old English is an example.
FF_DONTCARE Use default font.
FF_MODERN Fonts with constant stroke width (monospace), with or without serifs. Monospace fonts are usually modern. Pica, Elite, and CourierNew are examples.
FF_ROMAN Fonts with variable stroke width (proportional) and with serifs. MS Serif is an example.
FF_SCRIPT Fonts designed to look like handwriting. Script and Cursive are examples.
FF_SWISS Fonts with variable stroke width (proportional) and without serifs. MS Sans Serif is an example.

lfFaceName[LF_FACESIZE]

A null-terminated string that specifies the typeface name of the font. The length of this string must not exceed 32 TCHAR values, including the terminating NULL. The EnumFontFamiliesEx 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.

Remarks

The following situations do not support ClearType antialiasing:

  • Text is rendered on a printer.
  • Display set for 256 colors or less.
  • Text is rendered to a terminal server client.
  • The font is not a TrueType font or an OpenType font with TrueType outlines. For example, the following do not support ClearType antialiasing: Type 1 fonts, Postscript OpenType fonts without TrueType outlines, bitmap fonts, vector fonts, and device fonts.
  • The font has tuned embedded bitmaps, for any font sizes that contain the embedded bitmaps. For example, this occurs commonly in East Asian fonts.

Note

The wingdi.h header defines LOGFONT as an alias which automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps | UWP apps]
Minimum supported server Windows 2000 Server [desktop apps | UWP apps]
Header wingdi.h (include Windows.h)

See also

CreateFont

CreateFontIndirect

EnumFontFamiliesEx

Font and Text Structures

Fonts and Text Overview