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XTextExtents(3)			XLIB FUNCTIONS		       XTextExtents(3)

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

SYNTAX

       int XTextExtents(XFontStruct *font_struct, _Xconst  char	 *string,  int
	      nchars,  int  *direction_return,	int  *font_ascent_return,  int
	      *font_descent_return, XCharStruct	*overall_return);

       int XTextExtents16(XFontStruct *font_struct, _Xconst  XChar2b  *string,
	      int  nchars, int *direction_return, int *font_ascent_return, int
	      *font_descent_return, XCharStruct	*overall_return);

       int  XQueryTextExtents(Display  *display,  XID  font_ID,	 _Xconst  char
	      *string, int nchars, int *direction_return, int *font_ascent_re-
	      turn, int	*font_descent_return, XCharStruct *overall_return);

       int  XQueryTextExtents16(Display	*display, XID font_ID, _Xconst XChar2b
	      *string, int nchars, int *direction_return, int *font_ascent_re-
	      turn, int	*font_descent_return, XCharStruct *overall_return);

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

       display	 Specifies the connection to the X server.

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

       font_ascent_return
		 Returns the font ascent.

       font_descent_return
		 Returns the font descent.

       font_struct
		 Specifies the XFontStruct structure.

       nchars	 Specifies the number of characters in the character string.

       string	 Specifies the character string.

       overall_return
		 Returns  the overall size in the specified XCharStruct	struc-
		 ture.

DESCRIPTION
       The XTextExtents	and XTextExtents16 functions perform the size computa-
       tion locally and, thereby, avoid	the round-trip overhead	of  XQueryTex-
       tExtents	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 charac-
       ter-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	index-
       ing, 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	 func-
       tions query the X server	and, therefore,	suffer the round-trip overhead
       that is avoided by XTextExtents and XTextExtents16.  Both functions re-
       turn  a	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 charac-
       ter-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	index-
       ing,  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 de-
       fined default_char, the undefined characters in the string are also ig-
       nored.

       XQueryTextExtents and  XQueryTextExtents16  can	generate  BadFont  and
       BadGC errors.

DIAGNOSTICS
       BadFont	 A  value  for a Font or GContext argument does	not name a de-
		 fined Font.

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

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

X Version 11			 libX11	1.8.12		       XTextExtents(3)

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