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