NAME
XmbTextPerCharExtents, XwcTextPerCharExtents, Xutf8TextPerCharExtents - obtain
per-character information for a text string
SYNTAX
Status
XmbTextPerCharExtents(XFontSet font_set, char * string, int
num_bytes, XRectangle * ink_array_return, XRectangle *
logical_array_return, int array_size, int *
num_chars_return, XRectangle * overall_ink_return, XRectangle *
overall_logical_return);
Status
XwcTextPerCharExtents(XFontSet font_set, wchar_t * string, int
num_wchars, XRectangle * ink_array_return, XRectangle
*logical_array_return, int array_size, int
*num_chars_return, XRectangle * overall_ink_return, XRectangle
*overall_logical_return);
Status
Xutf8TextPerCharExtents(XFontSet font_set, char * string, int
num_bytes, XRectangle *ink_array_return, XRectangle *
logical_array_return, int array_size, int *
num_chars_return, XRectangle * overall_ink_return, XRectangle *
overall_logical_return);
ARGUMENTS
- array_size
- Specifies the size of ink_array_return and
logical_array_return. The caller must pass in arrays of this size.
- font_set
- Specifies the font set.
- ink_array_return
- Returns the ink dimensions for each character.
- logical_array_return
- Returns the logical dimensions for each character.
- num_bytes
- Specifies the number of bytes in the string argument.
- num_chars_return
- Returns the number of characters in the string
argument.
- num_wchars
- Specifies the number of characters in the string
argument.
- overall_ink_return
- Returns the overall ink extents of the entire string.
- overall_logical_return
- Returns the overall logical extents of the entire
string.
- string
- Specifies the character string.
DESCRIPTION
The
XmbTextPerCharExtents,
XwcTextPerCharExtents and
Xutf8TextPerCharExtents functions return the text dimensions of each
character of the specified text, using the fonts loaded for the specified font
set. Each successive element of ink_array_return and logical_array_return is
set to the successive character's drawn metrics, relative to the drawing
origin of the string and one rectangle for each character in the supplied text
string. The number of elements of ink_array_return and logical_array_return
that have been set is returned to num_chars_return.
Each element of ink_array_return is set to the bounding box of the corresponding
character's drawn foreground color. Each element of logical_array_return is
set to the bounding box that provides minimum spacing to other graphical
features for the corresponding character. Other graphical features should not
intersect any of the logical_array_return rectangles.
Note that an
XRectangle represents the effective drawing dimensions of
the character, regardless of the number of font glyphs that are used to draw
the character or the direction in which the character is drawn. If multiple
characters map to a single character glyph, the dimensions of all the
XRectangles of those characters are the same.
When the
XFontSet has missing charsets, metrics for each unavailable
character are taken from the default string returned by
XCreateFontSet
so that the metrics represent the text as it will actually be drawn. The
behavior for an invalid codepoint is undefined.
If the array_size is too small for the number of characters in the supplied
text, the functions return zero and num_chars_return is set to the number of
rectangles required. Otherwise, the functions return a nonzero value.
If the overall_ink_return or overall_logical_return argument is non-NULL,
XmbTextPerCharExtents,
XwcTextPerCharExtents and
Xutf8TextPerCharExtents return the maximum extent of the string's
metrics to overall_ink_return or overall_logical_return, as returned by
XmbTextExtents,
XwcTextExtents or
Xutf8TextExtents.
The function
Xutf8TextPerCharExtents is an extension introduced by The
XFree86 Project, Inc. in their 4.0.2 release. Its presence is indicated by the
macro
X_HAVE_UTF8_STRING.
SEE ALSO
XmbTextEscapement(3), XmbTextExtents(3)
Xlib - C Language X
Interface