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