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XCreateFontCursor(3) XLIB FUNCTIONS XCreateFontCursor(3)
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 *fore-
ground_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 *back-
ground_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 fore-
ground_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 back-
ground 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 pix-
els 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 cur-
sor. 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 XFree-
Font 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(3X11), XLoadFont(3X11), XRecolorCursor(3X11)
Xlib - C Language X Interface
X Version 11 libX11 1.2.1 XCreateFontCursor(3) |
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