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XTextExtents(3) 		 XLIB FUNCTIONS 		 XTextExtents(3)

NAME
     XTextExtents, XTextExtents16, XQueryTextExtents, XQueryTextExtents16 - com-
     pute 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_return,  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_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 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  char-
     acters  in the string.  The descent member is set to the maximum of the de-
     scent 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, unde-
     fined 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.

     The ascent member is set to the maximum of the ascent metrics of all  char-
     acters  in the string.  The descent member is set to the maximum of the de-
     scent 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, unde-
     fined 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(3), XTextWidth(3)
     Xlib - C Language X Interface

X Version 11			  libX11 1.8.13 		 XTextExtents(3)

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