XTextExtents(3X11)            X11 SDE 5.4R3.00            XTextExtents(3X11)


NAME
       XTextExtents, XTextExtents16, XQueryTextExtents, XQueryTextExtents16
       - compute or query text extents

SYNTAX
       XTextExtents(fontstruct, string, nchars, directionreturn,
       fontascentreturn,
                     fontdescentreturn, overallreturn)
             XFontStruct *fontstruct;
             char *string;
             int nchars;
             int *directionreturn;
             int *fontascentreturn, *fontdescentreturn;
             XCharStruct *overallreturn;


       XTextExtents16(fontstruct, string, nchars, directionreturn,
       fontascentreturn,
                       fontdescentreturn, overallreturn)
             XFontStruct *fontstruct;
             XChar2b *string;
             int nchars;
             int *directionreturn;
             int *fontascentreturn, *fontdescentreturn;
             XCharStruct *overallreturn;


       XQueryTextExtents(display, fontID, string, nchars, directionreturn,
       fontascentreturn,
                           fontdescentreturn, overallreturn)
             Display *display;
             XID fontID;
             char *string;
             int nchars;
             int *directionreturn;
             int *fontascentreturn, *fontdescentreturn;
             XCharStruct *overallreturn;

       XQueryTextExtents16(display, fontID, string, nchars,
       directionreturn, fontascentreturn,
                               fontdescentreturn, overallreturn)
             Display *display;
             XID fontID;
             XChar2b *string;
             int nchars;
             int *directionreturn;
             int *fontascentreturn, *fontdescentreturn;
             XCharStruct *overallreturn;

ARGUMENTS
       directionreturn
                 Returns the value of the direction hint (FontLeftToRight or
                 FontRightToLeft).




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XTextExtents(3X11)            X11 SDE 5.4R3.00            XTextExtents(3X11)


       display   Specifies the connection to the X server.

       fontID   Specifies either the font ID or the GContext ID that
                 contains the font.

       fontascentreturn
                 Returns the font ascent.

       fontdescentreturn
                 Returns the font descent.

       fontstruct
                 Specifies the XFontStruct structure.

       nchars    Specifies the number of characters in the character string.

       string    Specifies the character string.

       overallreturn
                 Returns the overall size in the specified XCharStruct
                 structure.

DESCRIPTION
       The XTextExtents and XTextExtents16 functions perform the size
       computation locally and, thereby, avoid the round-trip overhead of
       XQueryTextExtents and XQueryTextExtents16.  Both functions return an
       XCharStruct structure, whose members are set to the values as
       follows.

       The ascent member is set to the maximum of the ascent metrics of all
       characters in the string.  The descent member is set to the maximum
       of the descent metrics.  The width member is set to the sum of the
       character-width metrics of all characters in the string.  For each
       character in the string, let W be the sum of the character-width
       metrics of all characters preceding it in the string.  Let L be the
       left-side-bearing metric of the character plus W.  Let R be the
       right-side-bearing metric of the character plus W.  The lbearing
       member is set to the minimum L of all characters in the string.  The
       rbearing member is set to the maximum R.

       For fonts defined with linear indexing rather than 2-byte matrix
       indexing, each XChar2b structure is interpreted as a 16-bit number
       with byte1 as the most-significant byte.  If the font has no defined
       default character, undefined characters in the string are taken to
       have all zero metrics.

       The XQueryTextExtents and XQueryTextExtents16 functions return the
       bounding box of the specified 8-bit and 16-bit character string in
       the specified font or the font contained in the specified GC.  These
       functions query the X server and, therefore, suffer the round-trip
       overhead that is avoided by XTextExtents and XTextExtents16.  Both
       functions return a XCharStruct structure, whose members are set to
       the values as follows.




Licensed material--property of copyright holder(s)                         2

XTextExtents(3X11)            X11 SDE 5.4R3.00            XTextExtents(3X11)


       The ascent member is set to the maximum of the ascent metrics of all
       characters in the string.  The descent member is set to the maximum
       of the descent metrics.  The width member is set to the sum of the
       character-width metrics of all characters in the string.  For each
       character in the string, let W be the sum of the character-width
       metrics of all characters preceding it in the string.  Let L be the
       left-side-bearing metric of the character plus W.  Let R be the
       right-side-bearing metric of the character plus W.  The lbearing
       member is set to the minimum L of all characters in the string.  The
       rbearing member is set to the maximum R.

       For fonts defined with linear indexing rather than 2-byte matrix
       indexing, each XChar2b structure is interpreted as a 16-bit number
       with byte1 as the most-significant byte.  If the font has no defined
       default character, undefined characters in the string are taken to
       have all zero metrics.

       Characters with all zero metrics are ignored.  If the font has no
       defined default_char, the undefined characters in the string are also
       ignored.

       XQueryTextExtents and XQueryTextExtents16 can generate BadFont and
       BadGC errors.

DIAGNOSTICS
       BadFont   A value for a Font or GContext argument does not name a
                 defined Font.

       BadGC     A value for a GContext argument does not name a defined
                 GContext.

SEE ALSO
       XLoadFont(3X11), XTextWidth(3X11)
       Xlib - C Language X Interface























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