NAME
XCreateFontCursor, XCreatePixmapCursor, XCreateGlyphCursor - create
cursors
SYNTAX
#include <X11/cursorfont.h>
Cursor XCreateFontCursor(Display *display, unsigned int shape);
Cursor XCreatePixmapCursor(Display *display, Pixmap source, Pixmap
mask, XColor *foreground_color, XColor *background_color,
unsigned int x, unsigned int y);
Cursor XCreateGlyphCursor(Display *display, Font source_font, Font
mask_font, unsigned int source_char, unsigned int mask_char,
XColor *foreground_color, XColor *background_color);
ARGUMENTS
background_color
Specifies the RGB values for the background of the source.
display Specifies the connection to the X server.
foreground_color
Specifies the RGB values for the foreground of the source.
mask Specifies the cursor’s source bits to be displayed or None.
mask_char Specifies the glyph character for the mask.
mask_font Specifies the font for the mask glyph or None.
shape Specifies the shape of the cursor.
source Specifies the shape of the source cursor.
source_char
Specifies the character glyph for the source.
source_font
Specifies the font for the source glyph.
x
y Specify the x and y coordinates, which indicate the hotspot
relative to the source’s origin.
DESCRIPTION
X provides a set of standard cursor shapes in a special font named
cursor. Applications are encouraged to use this interface for their
cursors because the font can be customized for the individual display
type. The shape argument specifies which glyph of the standard fonts
to use.
The hotspot comes from the information stored in the cursor font. The
initial colors of a cursor are a black foreground and a white
background (see XRecolorCursor).
XCreateFontCursor can generate BadAlloc and BadValue errors.
The XCreatePixmapCursor function creates a cursor and returns the
cursor ID associated with it. The foreground and background RGB values
must be specified using foreground_color and background_color, even if
the X server only has a StaticGray or GrayScale screen. The foreground
color is used for the pixels set to 1 in the source, and the background
color is used for the pixels set to 0. Both source and mask, if
specified, must have depth one (or a BadMatch error results) but can
have any root. The mask argument defines the shape of the cursor. The
pixels set to 1 in the mask define which source pixels are displayed,
and the pixels set to 0 define which pixels are ignored. If no mask is
given, all pixels of the source are displayed. The mask, if present,
must be the same size as the pixmap defined by the source argument, or
a BadMatch error results. The hotspot must be a point within the
source, or a BadMatch error results.
The components of the cursor can be transformed arbitrarily to meet
display limitations. The pixmaps can be freed immediately if no
further explicit references to them are to be made. Subsequent drawing
in the source or mask pixmap has an undefined effect on the cursor.
The X server might or might not make a copy of the pixmap.
XCreatePixmapCursor can generate BadAlloc and BadPixmap errors.
The XCreateGlyphCursor function is similar to XCreatePixmapCursor
except that the source and mask bitmaps are obtained from the specified
font glyphs. The source_char must be a defined glyph in source_font,
or a BadValue error results. If mask_font is given, mask_char must be
a defined glyph in mask_font, or a BadValue error results. The
mask_font and character are optional. The origins of the source_char
and mask_char (if defined) glyphs are positioned coincidently and
define the hotspot. The source_char and mask_char need not have the
same bounding box metrics, and there is no restriction on the placement
of the hotspot relative to the bounding boxes. If no mask_char is
given, all pixels of the source are displayed. You can free the fonts
immediately by calling XFreeFont if no further explicit references to
them are to be made.
For 2-byte matrix fonts, the 16-bit value should be formed with the
byte1 member in the most significant byte and the byte2 member in the
least significant byte.
XCreateGlyphCursor can generate BadAlloc, BadFont, and BadValue errors.
DIAGNOSTICS
BadAlloc The server failed to allocate the requested resource or
server memory.
BadFont A value for a Font or GContext argument does not name a
defined Font.
BadMatch Some argument or pair of arguments has the correct type and
range but fails to match in some other way required by the
request.
BadPixmap A value for a Pixmap argument does not name a defined Pixmap.
BadValue Some numeric value falls outside the range of values accepted
by the request. Unless a specific range is specified for an
argument, the full range defined by the argument’s type is
accepted. Any argument defined as a set of alternatives can
generate this error.
SEE ALSO
XDefineCursor(3), XLoadFont(3), XRecolorCursor(3)
Xlib - C Language X Interface