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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, char *string,	int nchars,
	      int *direction_return, int *font_ascent_return, int *font_de-
	      scent_return, XCharStruct	*overall_return);

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

       int XQueryTextExtents16(Display *display, XID font_ID, XChar2b *string,
	      int nchars, int *direction_return, int *font_ascent_return, 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	1.6.5		       XTextExtents(3)

NAME | SYNTAX | ARGUMENTS | DESCRIPTION | DIAGNOSTICS | SEE ALSO

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