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XFree(3X11)

NAME

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

SYNTAX

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;

ARGUMENTS

classSpecifies the class of the screen. 

depthSpecifies the depth of the screen. 

displaySpecifies the connection to the X server. 

nitems_return
Returns the number of matching visual structures.

screenSpecifies the screen. 

visualSpecifies the visual type. 

vinfo_maskSpecifies the visual mask value. 

vinfo_returnReturns 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;
unsigned 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(3X11)
Xlib − C Language X Interface

X Version 11

Typewritten Software • bear@typewritten.org • Edmonds, WA 98026