Retrieves the widths of consecutive characters in a specified range from the current TrueType font.
BOOL GetCharABCWidths( UINT nFirstChar, UINT nLastChar, LPABC lpabc ) const; BOOL GetCharABCWidths( UINT nFirstChar, UINT nLastChar, LPABCFLOAT lpABCF ) const;
The widths are returned in logical units. This function succeeds only with TrueType fonts.
The TrueType rasterizer provides "ABC" character spacing after a specific point size has been selected. "A" spacing is the distance that is added to the current position before placing the glyph. "B" spacing is the width of the black part of the glyph. "C" spacing is added to the current position to account for the white space to the right of the glyph. The total advanced width is given by A + B + C.
When the GetCharABCWidths member function retrieves negative "A" or "C" widths for a character, that character includes underhangs or overhangs.
To convert the ABC widths to font design units, an application should create a font whose height (as specified in the lfHeight member of the LOGFONT structure) is equal to the value stored in the ntmSizeEM member of the NEWTEXTMETRIC structure. (The value of the ntmSizeEM member can be retrieved by calling the EnumFontFamilies Windows function.)
The ABC widths of the default character are used for characters that are outside the range of the currently selected font.
To retrieve the widths of characters in non-TrueType fonts, applications should use the GetCharWidth Windows function.