table of contents
XGetVisualInfo(3) | XLIB FUNCTIONS | XGetVisualInfo(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
libX11 1.7.0 | X Version 11 |