TEXTMETRIC

typedef struct tagTEXTMETRIC {
    short  tmHeight;           // see below
    short  tmAscent;           // see below
    short  tmDescent;          // see below
    short  tmInternalLeading;  // see below
    short  tmExternalLeading;  // recommended amount of leading
    short  tmAveCharWidth;     // avg. width of characters in font
    short  tmMaxCharWidth;     // max. width of any character in font
    short  tmWeight;           // weight of font
    BYTE   tmItalic;           // italic font if value is nonzero
    BYTE   tmUnderlined;       // underlined font if value is nonzero
    BYTE   tmStruckOut;        // struckout font if value is nonzero
    BYTE   tmFirstChar;        // value of first character for font
    BYTE   tmLastChar;         // value of last character for font
    BYTE   tmDefaultChar;      // see below
    BYTE   tmBreakChar;        // see below
    BYTE   tmPitchAndFamily;   // see below
    BYTE   tmCharSet;          // see below
    short  tmOverhang;         // see below
    short  tmDigitizedAspectX; // see below
    short  tmDigitizedAspectY; // see below
} TEXTMETRIC;

Contains a list of the basic metrics of a physical font.

tmHeight

Height of the character cell. This member is equal to the sum of the tmAscent and tmDescent members.

tmAscent

Ascent of the character cell (the height of the cell measured from the baseline).

tmDescent

Descent of the character cell (the height of the cell measured from the baseline to the bottom of the cell).

tmInternalLeading

Amount of internal leading. It is equal to the difference between the cell height (as expressed by the tmHeight member) and the maximum height of any character in the font (excluding the height of accent marks).

tmDefaultChar

Value of the character that is to be substituted for characters not in the font.

tmBreakChar

Value of the character used to define word breaks for text justification.

tmPitchAndFamily

Font pitch and font family. This member is a combination of one pitch and one family value. The pitch value can be one of these values:

DEFAULT_PITCH (0x00)	Chooses a reasonable font.
FIXED_PITCH (0x01)	Chooses a fixed-pitch font.
VARIABLE_PITCH (0x02)	Chooses a variable-pitch font.

The font-family value can be one of these values:

FF_DONTCARE (0x00)	Chooses a reasonable font.
FF_ROMAN (0x10)	Chooses a variable-pitch font with serifs.
FF_SWISS (0x20)	Chooses a variable-pitch fonts without serifs.
FF_MODERN (0x30)	Chooses a fixed-pitch font.
FF_SCRIPT (0x40)	Chooses a cursive or script font.
FF_DECORATIVE (0x50)	Chooses a novelty font.

tmCharSet

Character set of the font. Can be one of these values:

ANSI_CHARSET (0x00)	ANSI character set.
SYMBOL_CHARSET (0x02)	Symbol character set.
OEM_CHARSET (0xFF)	OEM-specific character set. The characters and corresponding character codes depend on the computer.

tmOverhang

Amount of additional, synthesized width of a character or character string. This member may be is nonzero if the driver synthesizes character attributes, such as bold or italic, by modifying an existing font.

tmDigitizedAspectX

Horizontal aspect ratio for which this font was designed. This member is equal to the dfHorizRes member of the FONTINFO structure.

tmDigitizedAspectY

Vertical aspect ratio for which this font was designed. This member is equal to the dfVertRes member of the FONTINFO structure.

GDI makes a string bold by expanding the intracharacter spacing and overstriking with an offset; the overhang is the distance by which the overstrike is offset. GDI italicizes a font by skewing the string, and the overhang is the amount the top of the font is skewed past the bottom of the font.