[vlc-devel] [PATCH 4/4] win32: Send fullscreen to specific monitor

[Gabriel Luci]

This reads the id parameter as the name of the monitor that should be
used. If anything goes wrong, it will fall back to the monitor the
window is already on (which is what it always did before).

---
 modules/video_output/win32/window.c | 72 +++++++++++++++++++++++++++++++++----
 1 file changed, 65 insertions(+), 7 deletions(-)

diff --git a/modules/video_output/win32/window.c b/modules/video_output/win32/window.c
index 50e172b9b4..eefaed256e 100644
--- a/modules/video_output/win32/window.c
+++ b/modules/video_output/win32/window.c
@@ -37,6 +37,7 @@
 #include <vlc_actions.h>
 
 #include <shellapi.h>                                         /* ExtractIcon */
+#include <vlc_charset.h>                                      /* FromWide */
 
 #define RECTWidth(r)   (LONG)((r).right - (r).left)
 #define RECTHeight(r)  (LONG)((r).bottom - (r).top)
@@ -153,9 +154,37 @@ static void SetTitle(vout_window_t *wnd, const char *title)
     PostMessage( sys->hwnd, WM_VLC_CHANGE_TEXT, 0, 0 );
 }
 
+typedef struct enum_monitors_callback_params_t {
+    bool is_monitor_found;
+    const char *psz_name_to_find;
+    MONITORINFOEX *found_monitor_info;
+} enum_monitors_callback_params_t;
+
+static BOOL CALLBACK EnumDisplayMonitorsCallback(HMONITOR hMonitor, HDC hdcMonitor, LPRECT lprcMonitor, LPARAM dwData)
+{
+    /* this is called for each active monitor */
+
+    VLC_UNUSED(hdcMonitor);
+    VLC_UNUSED(lprcMonitor);
+
+    MONITORINFOEX mi;
+    mi.cbSize = sizeof(MONITORINFOEX);
+    if (!GetMonitorInfo(hMonitor, (LPMONITORINFO) &mi)) return true;
+
+    enum_monitors_callback_params_t *params = (enum_monitors_callback_params_t*) dwData;
+    char *psz_monitor_name = FromWide(mi.szDevice);
+    if (!strcmp(psz_monitor_name, params->psz_name_to_find))
+    {
+        /* the monitor name matches what we're looking for */
+        params->is_monitor_found = true;
+        params->found_monitor_info = &mi;
+    }
+    free(psz_monitor_name);
+    return !params->is_monitor_found;
+}
+
 static void SetFullscreen(vout_window_t *wnd, const char *id)
 {
-    VLC_UNUSED(id);
     msg_Dbg(wnd, "entering fullscreen mode");
     vout_window_sys_t *sys = wnd->sys;
 
@@ -167,12 +196,41 @@ static void SetFullscreen(vout_window_t *wnd, const char *id)
     /* Change window style, no borders and no title bar */
     SetWindowLong(sys->hwnd, GWL_STYLE, WS_CLIPCHILDREN | WS_VISIBLE);
 
-    /* Retrieve current window position so fullscreen will happen
-     * on the right screen */
-    HMONITOR hmon = MonitorFromWindow(sys->hwnd, MONITOR_DEFAULTTONEAREST);
-    MONITORINFO mi;
-    mi.cbSize = sizeof(MONITORINFO);
-    if (GetMonitorInfo(hmon, &mi))
+    /* Figure out which monitor we should be using */
+    MONITORINFOEX mi;
+    bool is_monitor_found = false;
+
+    if (id)
+    {
+        /* We're being told to use a specific monitor, so see if we can find an
+         * active monitor with the same name */
+        enum_monitors_callback_params_t params = {
+            .is_monitor_found = false,
+            .psz_name_to_find = id
+        };
+        EnumDisplayMonitors(NULL, NULL, &EnumDisplayMonitorsCallback, (LPARAM) &params);
+
+        if (params.is_monitor_found)
+        {
+            is_monitor_found = true;
+            mi = *(params.found_monitor_info);
+        }
+        else
+        {
+            msg_Dbg(wnd, "display device with name \"%s\" was requested, but no such device exists. Falling back to primary", id);
+        }
+    }
+
+    if (!is_monitor_found)
+    {
+        /* fall back to using the screen the window is currently mostly on */
+        HMONITOR hmon;
+        hmon = MonitorFromWindow(sys->hwnd, MONITOR_DEFAULTTONEAREST);
+        mi.cbSize = sizeof(MONITORINFOEX);
+        is_monitor_found = GetMonitorInfo(hmon, (LPMONITORINFO) &mi);
+    }
+    
+    if (is_monitor_found)
         SetWindowPos(sys->hwnd, 0,
                      mi.rcMonitor.left,
                      mi.rcMonitor.top,
-- 
2.11.0