在X11中获取有关距鼠标光标最近的显示器的信息

Question

我需要获取诸如多显示器系统中距鼠标光标位置最近的显示器的大小和坐标之类的信息。 我之前在Windows中已经做到了，我想知道如何在Linux X11中做到这一点。

使用下面的代码，我可以测量整个屏幕尺寸的总和，但不能单独测量每个显示器。

Screen *screen = DefaultScreenOfDisplay(DisplayHandle);
int xx = screen->width / 2 - Settings::WindowWidth / 2;
int yy = screen->height / 2 - Settings::WindowHeight / 2;

我以前的代码：

POINT mouse_position;
GetCursorPos(&mouse_position);
HMONITOR hMonitor = MonitorFromPoint(mouse_position, MONITOR_DEFAULTTOPRIMARY);
MONITORINFOEX monitor_info;
memset(&monitor_info, 0, sizeof(MONITORINFOEX));
monitor_info.cbSize = sizeof(MONITORINFOEX);
GetMonitorInfo(hMonitor, &monitor_info);

// CREATE WINDOW IN CENTER OF MONITOR //
int edge = GetSystemMetrics(SM_CXEDGE);
int fixed_frame = GetSystemMetrics(SM_CXFIXEDFRAME);
int monitor_width =  monitor_info.rcMonitor.right - monitor_info.rcMonitor.left;
int monitor_height =  monitor_info.rcMonitor.bottom - monitor_info.rcMonitor.top;
int xx = monitor_width / 2 - Settings::WindowWidth / 2;
int yy = monitor_height / 2 - Settings::WindowHeight / 2;
int win_x = xx - edge + monitor_info.rcMonitor.left;
int win_y = yy - fixed_frame + monitor_info.rcMonitor.top;

谢谢

Answer 1

如果您有两个构成单个桌面的显示器，请使用Xinerama扩展。 下面的代码选择了可用显示器的最大屏幕，但是您会明白的。

#include <X11/extensions/Xinerama.h>

// By default go fullscreen
m_winWidth = DisplayWidth (m_display, m_screenNo);
m_winHeight = DisplayHeight (m_display, m_screenNo);
// But, with Xinerama, use the largest physical screen
if (XineramaIsActive (m_display))
{
  int m = 0;
  int pixels = 0;

  XineramaScreenInfo *xs = XineramaQueryScreens (m_display, &m);

  if (0 != xs && m > 0)
  {
    for (int i = 0; i < m; i++)
    {
      //printf ("%dx%d, [%d, %d] %d\n", xs[i].width, xs[i].height, xs[i].x_org, xs[i].y_org, xs[i].screen_number);
      if (xs[i].width * xs[i].height > pixels)
      {
        m_xineramaScreen = xs[i].screen_number; // pick screen
        pixels = xs[i].width * xs[i].height;
        m_winWidth = xs[i].width;
        m_winHeight = xs[i].height;
      }
    }

    XFree (xs);
  }
}