XContextDependentDrawing (3) - Linux Manuals

XContextDependentDrawing: obtain fontset information

NAME

XFontsOfFontSet, XBaseFontNameListOfFontSet, XLocaleOfFontSet, XContextDependentDrawing, XContextualDrawing, XDirectionalDependentDrawing - obtain fontset information

SYNTAX

int XFontsOfFontSet(XFontSet font_set, XFontStruct ***font_struct_list_return, char ***font_name_list_return);
char *XBaseFontNameListOfFontSet(XFontSet font_set);
char *XLocaleOfFontSet(XFontSet font_set);
Bool XContextDependentDrawing(XFontSet font_set);
Bool XContextualDrawing(XFontSet font_set);
Bool XDirectionalDependentDrawing(XFontSet font_set);

ARGUMENTS

font_set
Specifies the font set.
font_name_list_return
Returns the list of font names.
font_struct_list_return
Returns the list of font structs.

DESCRIPTION

The XFontsOfFontSet function returns a list of one or more XFontStructs and font names for the fonts used by the Xmb and Xwc layers for the given font set. A list of pointers to the XFontStruct structures is returned to font_struct_list_return. A list of pointers to null-terminated, fully specified font name strings in the locale of the font set is returned to font_name_list_return. The font_name_list order corresponds to the font_struct_list order. The number of XFontStruct structures and font names is returned as the value of the function.

Because it is not guaranteed that a given character will be imaged using a single font glyph, there is no provision for mapping a character or default string to the font properties, font ID, or direction hint for the font for the character. The client may access the XFontStruct list to obtain these values for all the fonts currently in use.

Xlib does not guarantee that fonts are loaded from the server at the creation of an XFontSet. Xlib may choose to cache font data, loading it only as needed to draw text or compute text dimensions. Therefore, existence of the per_char metrics in the XFontStruct structures in the XFontStructSet is undefined. Also, note that all properties in the XFontStruct structures are in the STRING encoding.

The XFontStruct and font name lists are owned by Xlib and should not be modified or freed by the client. They will be freed by a call to XFreeFontSet with the associated XFontSet. Until freed, their contents will not be modified by Xlib.

The XBaseFontNameListOfFontSet function returns the original base font name list supplied by the client when the XFontSet was created. A null-terminated string containing a list of comma-separated font names is returned as the value of the function. White space may appear immediately on either side of separating commas.

If XCreateFontSet obtained an XLFD name from the font properties for the font specified by a non-XLFD base name, the XBaseFontNameListOfFontSet function will return the XLFD name instead of the non-XLFD base name.

The base font name list is owned by Xlib and should not be modified or freed by the client. It will be freed by a call to XFreeFontSet with the associated XFontSet. Until freed, its contents will not be modified by Xlib.

The XLocaleOfFontSet function returns the name of the locale bound to the specified XFontSet, as a null-terminated string.

The returned locale name string is owned by Xlib and should not be modified or freed by the client. It may be freed by a call to XFreeFontSet with the associated XFontSet. Until freed, it will not be modified by Xlib.

The XContextDependentDrawing function returns True if the drawing functions implement implicit text directionality or if text drawn with the font_set might include context-dependent drawing; otherwise, it returns False.

The XContextualDrawing function returns True if text drawn with the font set might include context-dependent drawing; otherwise, it returns False.

The XDirectionalDependentDrawing function returns True if the drawing functions implement implicit text directionality; otherwise, it returns False.

SEE ALSO

XCreateFontSet(3), XCreateOM(3), XCreateOC(3), XExtentsOfFontSet(3), XFontSetExtents(3)
Xlib - C Language X Interface