XdbeGetVisualInfo - Get dbe Visual Informations


#include <X11/extensions/Xdbe.h>

XdbeScreenVisualInfo *XdbeGetVisualInfo(
Display *dpy,
Drawable *screen_specifiers,
int *num_screens)


This function returns information about which visuals support double buffering. The argument num_screens specifies how many elements there are in the screen_specifiers list. Each drawable in screen_specifiers designates a screen for which the supported visuals are being requested. If num_screens is zero, information for all screens is requested. In this case, upon return from this function, num_screens will be set to the number of screens that were found. If an error occurs, this function returns NULL, else it returns a pointer to a list of XdbeScreenVisualInfo structures of length num_screens. The nth element in the returned list corresponds to the nth drawable in the screen_specifiers list, unless num_screens was passed in with the value zero, in which case the nth element in the returned list corresponds to the nth screen of the server, starting with screen zero. The XdbeScreenVisualInfo structure has the following fields:

int count
XdbeVisualInfo *visinfo

count specifies the number of items in visinfo. visinfo specifies a list of visuals, depths, and performance hints for this screen.

The XdbeVisualInfo structure has the following fields:

VisualID visual
int depth
int perflevel

visual specifies one visual ID that supports double-buffering. depth specifies the depth of the visual. perflevel is a performance hint.

The only operation defined on a perflevel is comparison to a perflevel of another visual on the same screen. The visual having the higher perflevel is likely to have better double-buffering graphics performance than the visual having the lower perflevel. Nothing can be deduced from the following: the magnitude of the difference of two perflevels, a perflevel value in isolation, or comparing perflevels from different servers.



One or more values passed in screen_specifiers is not a valid drawable.


DBE, XdbeAllocateBackBufferName(), XdbeBeginIdiom(), XdbeDeallocateBackBufferName(), XdbeEndIdiom(), XdbeFreeVisualInfo(), XdbeGetBackBufferAttributes(), XdbeQueryExtension(), XdbeSwapBuffers().

More Linux Commands

encoding(3pm) - allows you to write your script in non-ascii
This module is deprecated under perl 5.18. It uses a mechanism provided by perl that is deprecated under 5.18 and higher, and may be removed in a future version

htpasswd2(1) - Manage user files for basic authentication...
htpasswd is used to create and update the flat-files used to store usernames and password for basic authentication of HTTP users. If htpasswd cannot access a fi

j0l(3) - Bessel functions of the first kind - Linux man page
The j0() and j1() functions return Bessel functions of x of the first kind of orders 0 and 1, respectively. The jn() function returns the Bessel function of x o

snmpvacm(1) - creates and maintains SNMPv3 View-based Access
snmpvacm is an SNMP application that can be used to do simple maintenance on the View-based Control Module (VACM) tables of an SNMP agent. The SNMPv3 VACM speci

mvwaddch(3ncurses) - add a character (with attributes) to a
The addch, waddch, mvaddch and mvwaddch routines put the character ch into the given window at its current window position, which is then advanced. They are ana

cytune(8) - tune driver parameters for Cyclades-Z multiport
cytune queries and modifies the interruption threshold for the Cyclades driver. Each serial line on a Cyclades card has a 12-byte FIFO for input (and another 12

set_tid_address(2) - set pointer to thread ID (Man Page)....
For each process, the kernel maintains two attributes (addresses) called set_child_tid and clear_child_tid. These two attributes contain the value NULL by defau

pwrite(2) - read from or write to a file descriptor at a giv
pread() reads up to count bytes from file descriptor fd at offset offset (from the start of the file) into the buffer starting at buf. The file offset is not ch

idmapd.conf(5) - (unknown subject) - Linux manual page......
The idmapd.conf configuration file consists of several sections, initiated by strings of the form [General] and [Mapping]. Each section may contain lines of the

pow10(3) - base-10 power functions - Linux manual page......
The pow10() function returns the value of 10 raised to the power x. VERSIONS These functions first appeared in glibc in version 2.1. CONFORMING TO This is a GNU

TYPE_ALNUM(3form) - form system global variables (Man Page)
These are building blocks for the form library, defining fields that can be created using set_fieldtype(3X). Each provides functions for field- and character-va

thread(n) Extension for script access to Tcl threading......
The thread extension creates threads that contain Tcl interpreters, and it lets you send scripts to those threads for evaluation. Additionaly, it provides scrip

We can't live, work or learn in freedom unless the software we use is free.