XMatchVisualInfo (3)

Leading comments

Copyright \(co 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1994, 1996 X Consortium

Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the foll...

(The comments found at the beginning of the groff file "man3/XMatchVisualInfo.3".)

NAME

XGetVisualInfo, XMatchVisualInfo, XVisualIDFromVisual, XVisualInfo - obtain visual information and visual structure

SYNTAX

XVisualInfo *XGetVisualInfo(Display *display, long vinfo_mask, XVisualInfo *vinfo_template, int *nitems_return);

Status XMatchVisualInfo(Display *display, int screen, int depth, int class, XVisualInfo *vinfo_return);

VisualID XVisualIDFromVisual(Visual *visual);

ARGUMENTS

class

Specifies the class of the screen.

depth

Specifies the depth of the screen.

display

Specifies the connection to the X server.

nitems_return

Returns the number of matching visual structures.

screen

Specifies the screen.

visual

Specifies the visual type.

vinfo_mask

Specifies the visual mask value.

vinfo_return

Returns the matched visual information.

vinfo_template

Specifies the visual attributes that are to be used in matching the visual structures.

DESCRIPTION

The XGetVisualInfo function returns a list of visual structures that have attributes equal to the attributes specified by vinfo_template. If no visual structures match the template using the specified vinfo_mask, XGetVisualInfo returns a NULL. To free the data returned by this function, use XFree.

The XMatchVisualInfo function returns the visual information for a visual that matches the specified depth and class for a screen. Because multiple visuals that match the specified depth and class can exist, the exact visual chosen is undefined. If a visual is found, XMatchVisualInfo returns nonzero and the information on the visual to vinfo_return. Otherwise, when a visual is not found, XMatchVisualInfo returns zero.

The XVisualIDFromVisual function returns the visual ID for the specified visual type.

STRUCTURES

The XVisualInfo structure contains:

/* Visual information mask bits */

#define	VisualNoMask	0x0
#define	VisualIDMask	0x1
#define	VisualScreenMask	0x2
#define	VisualDepthMask	0x4
#define	VisualClassMask	0x8
#define	VisualRedMaskMask	0x10
#define	VisualGreenMaskMask	0x20
#define	VisualBlueMaskMask	0x40
#define	VisualColormapSizeMask	0x80
#define	VisualBitsPerRGBMask	0x100
#define	VisualAllMask	0x1FF

/* Values */

typedef struct {
        Visual *visual;
        VisualID visualid;
        int screen;
        int depth;
        int class;
        unsigned long red_mask;
        unsigned long green_mask;
        unsigned long blue_mask;
        int colormap_size;
        int bits_per_rgb;
} XVisualInfo;

SEE ALSO

XFree(3)
Xlib - C Language X Interface