XGetVisualInfo(3X)                             XGetVisualInfo(3X)



NAME
     XGetVisualInfo, XMatchVisualInfo, XVisualIDFromVisual -  get
     visual information and manipulate the XVisualInfo structure

SYNOPSIS
     XVisualInfo *XGetVisualInfo (display, vinfo-mask,
     vinfo-template, nitems-return)
     Display *display;
     long vinfo-mask;
     XVisualInfo *vinfo-template;
     int *nitems-return

     Status XMatchVisualInfo (display, screen, depth,
     class, vinfo-return)
     Display *display;
     int screen;
     int depth;
     int class;
     XVisualInfo *vinfo-return

     VisualID XVisualIDFromVisual (visual) Visual *visual;

DESCRIPTION
     The XGetVisualInfo function returns a list of visual struc-
     tures that match the attributes specified by vinfo-template.
     If no visual structures match vinfo-template using the
     specified vinfo-mask, XGetVisualInfo returns a null. To free
     the data returned by XGetVisualInfo, use XFree.

     The XMatchVisualInfo function obtains the visual information
     that matches the specified depth and class of the 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 is available in vinfo-return.
     Otherwise, when a visual is not found, XMatchVisualInfo re-
     turns zero.

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















November, 1990                                                  1

XGetVisualInfo(3X)                             XGetVisualInfo(3X)



   Arguments
     These functions accept the following 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.

     vinfo-mask
             Specifies the visual mask value.

     vinfo-return
             Returns the matching visual information.

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

     visual  Specifies the visual type.

   Structures
     The XVisualInfo structure is defined as follows.

     /* 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;
       unsigned int depth;
       int class;
       unsigned long red_mask;
       unsigned long green_mask;
       unsigned long blue_mask;
       int colormap_size;



2                                                  November, 1990

XGetVisualInfo(3X)                             XGetVisualInfo(3X)



       int bits_per_rgb;
     } XVisualInfo;

SEE ALSO
     XFree(3X)

     Xlib - C Language Interface

















































November, 1990                                                  3