Add tracking of which window 'owns' a monitor

src/cocoa_window.m

@@ -73,9 +73,9 @@ static float transformY(float y)
     return CGDisplayBounds(CGMainDisplayID()).size.height - y;
 }
 
-// Enter full screen mode
+// Make the specified window and its video mode active on its monitor
 //
-static GLFWbool enterFullscreenMode(_GLFWwindow* window)
+static GLFWbool acquireMonitor(_GLFWwindow* window)
 {
     const GLFWbool status = _glfwSetVideoModeNS(window->monitor, &window->videoMode);
     const CGRect bounds = CGDisplayBounds(window->monitor->ns.displayID);
@@ -85,14 +85,20 @@ static GLFWbool enterFullscreenMode(_GLFWwindow* window)
                                     bounds.size.height);
 
     [window->ns.object setFrame:frame display:YES];
+
     _glfwPlatformFocusWindow(window);
+    _glfwInputMonitorWindowChange(window->monitor, window);
     return status;
 }
 
-// Leave full screen mode
+// Remove the window and restore the original video mode
 //
-static void leaveFullscreenMode(_GLFWwindow* window)
+static void releaseMonitor(_GLFWwindow* window)
 {
+    if (window->monitor->window != window)
+        return;
+
+    _glfwInputMonitorWindowChange(window->monitor, NULL);
     _glfwRestoreVideoModeNS(window->monitor);
 }
 
@@ -219,7 +225,7 @@ static const NSRange kEmptyRange = { NSNotFound, 0 };
 - (void)windowDidMiniaturize:(NSNotification *)notification
 {
     if (window->monitor)
-        leaveFullscreenMode(window);
+        releaseMonitor(window);
 
     _glfwInputWindowIconify(window, GLFW_TRUE);
 }
@@ -227,7 +233,7 @@ static const NSRange kEmptyRange = { NSNotFound, 0 };
 - (void)windowDidDeminiaturize:(NSNotification *)notification
 {
     if (window->monitor)
-        enterFullscreenMode(window);
+        acquireMonitor(window);
 
     _glfwInputWindowIconify(window, GLFW_FALSE);
 }
@@ -999,7 +1005,7 @@ int _glfwPlatformCreateWindow(_GLFWwindow* window,
     if (window->monitor)
     {
         _glfwPlatformShowWindow(window);
-        if (!enterFullscreenMode(window))
+        if (!acquireMonitor(window))
             return GLFW_FALSE;
     }
 
@@ -1011,7 +1017,7 @@ void _glfwPlatformDestroyWindow(_GLFWwindow* window)
     [window->ns.object orderOut:nil];
 
     if (window->monitor)
-        leaveFullscreenMode(window);
+        releaseMonitor(window);
 
     if (window->context.api != GLFW_NO_API)
         _glfwDestroyContextNSGL(window);
@@ -1070,7 +1076,7 @@ void _glfwPlatformGetWindowSize(_GLFWwindow* window, int* width, int* height)
 void _glfwPlatformSetWindowSize(_GLFWwindow* window, int width, int height)
 {
     if (window->monitor)
-        enterFullscreenMode(window);
+        acquireMonitor(window);
     else
         [window->ns.object setContentSize:NSMakeSize(width, height)];
 }

src/internal.h

@@ -381,6 +381,9 @@ struct _GLFWmonitor
     // Physical dimensions in millimeters.
     int             widthMM, heightMM;
 
+    // The window whose video mode is current on this monitor
+    _GLFWwindow*    window;
+
     GLFWvidmode*    modes;
     int             modeCount;
     GLFWvidmode     currentMode;
@@ -911,6 +914,10 @@ void _glfwInputCursorEnter(_GLFWwindow* window, GLFWbool entered);
  */
 void _glfwInputMonitorChange(void);
 
+/*! @ingroup event
+ */
+void _glfwInputMonitorWindowChange(_GLFWmonitor* monitor, _GLFWwindow* window);
+
 /*! @brief Notifies shared code of an error.
  *  @param[in] error The error code most suitable for the error.
  *  @param[in] format The `printf` style format string of the error

src/monitor.c

@@ -158,6 +158,11 @@ void _glfwInputMonitorChange(void)
     _glfwFreeMonitors(monitors, monitorCount);
 }
 
+void _glfwInputMonitorWindowChange(_GLFWmonitor* monitor, _GLFWwindow* window)
+{
+    monitor->window = window;
+}
+
 
 //////////////////////////////////////////////////////////////////////////
 //////                       GLFW internal API                      //////

src/win32_window.c

@@ -328,9 +328,9 @@ static int translateKey(WPARAM wParam, LPARAM lParam)
     return _glfw.win32.publicKeys[HIWORD(lParam) & 0x1FF];
 }
 
-// Enter full screen mode
+// Make the specified window and its video mode active on its monitor
 //
-static GLFWbool enterFullscreenMode(_GLFWwindow* window)
+static GLFWbool acquireMonitor(_GLFWwindow* window)
 {
     GLFWvidmode mode;
     GLFWbool status;
@@ -344,13 +344,18 @@ static GLFWbool enterFullscreenMode(_GLFWwindow* window)
     SetWindowPos(window->win32.handle, HWND_TOPMOST,
                  xpos, ypos, mode.width, mode.height, SWP_NOCOPYBITS);
 
+    _glfwInputMonitorWindowChange(window->monitor, window);
     return status;
 }
 
-// Leave full screen mode
+// Remove the window and restore the original video mode
 //
-static void leaveFullscreenMode(_GLFWwindow* window)
+static void releaseMonitor(_GLFWwindow* window)
 {
+    if (window->monitor->window != window)
+        return;
+
+    _glfwInputMonitorWindowChange(window->monitor, NULL);
     _glfwRestoreVideoModeWin32(window->monitor);
 }
 
@@ -597,7 +602,7 @@ static LRESULT CALLBACK windowProc(HWND hWnd, UINT uMsg,
             {
                 window->win32.iconified = GLFW_TRUE;
                 if (window->monitor)
-                    leaveFullscreenMode(window);
+                    releaseMonitor(window);
 
                 _glfwInputWindowIconify(window, GLFW_TRUE);
             }
@@ -606,7 +611,7 @@ static LRESULT CALLBACK windowProc(HWND hWnd, UINT uMsg,
             {
                 window->win32.iconified = GLFW_FALSE;
                 if (window->monitor)
-                    enterFullscreenMode(window);
+                    acquireMonitor(window);
 
                 _glfwInputWindowIconify(window, GLFW_FALSE);
             }
@@ -971,7 +976,7 @@ int _glfwPlatformCreateWindow(_GLFWwindow* window,
     if (window->monitor)
     {
         _glfwPlatformShowWindow(window);
-        if (!enterFullscreenMode(window))
+        if (!acquireMonitor(window))
             return GLFW_FALSE;
     }
 
@@ -981,7 +986,7 @@ int _glfwPlatformCreateWindow(_GLFWwindow* window,
 void _glfwPlatformDestroyWindow(_GLFWwindow* window)
 {
     if (window->monitor)
-        leaveFullscreenMode(window);
+        releaseMonitor(window);
 
     if (window->context.api != GLFW_NO_API)
     {
@@ -1088,7 +1093,7 @@ void _glfwPlatformGetWindowSize(_GLFWwindow* window, int* width, int* height)
 void _glfwPlatformSetWindowSize(_GLFWwindow* window, int width, int height)
 {
     if (window->monitor)
-        enterFullscreenMode(window);
+        acquireMonitor(window);
     else
     {
         int fullWidth, fullHeight;

src/x11_window.c

@@ -711,10 +711,12 @@ static void pushSelectionToManager(_GLFWwindow* window)
     }
 }
 
-// Enter full screen mode
+// Make the specified window and its video mode active on its monitor
 //
-static void enterFullscreenMode(_GLFWwindow* window)
+static GLFWbool acquireMonitor(_GLFWwindow* window)
 {
+    GLFWbool status;
+
     if (_glfw.x11.saver.count == 0)
     {
         // Remember old screen saver settings
@@ -731,7 +733,7 @@ static void enterFullscreenMode(_GLFWwindow* window)
 
     _glfw.x11.saver.count++;
 
-    _glfwSetVideoModeX11(window->monitor, &window->videoMode);
+    status = _glfwSetVideoModeX11(window->monitor, &window->videoMode);
 
     if (_glfw.x11.NET_WM_BYPASS_COMPOSITOR)
     {
@@ -778,12 +780,19 @@ static void enterFullscreenMode(_GLFWwindow* window)
                       _glfw.x11.NET_WM_STATE_FULLSCREEN,
                       0, 1, 0);
     }
+
+    _glfwInputMonitorWindowChange(window->monitor, window);
+    return status;
 }
 
-// Leave full screen mode
+// Remove the window and restore the original video mode
 //
-static void leaveFullscreenMode(_GLFWwindow* window)
+static void releaseMonitor(_GLFWwindow* window)
 {
+    if (window->monitor->window != window)
+        return;
+
+    _glfwInputMonitorWindowChange(window->monitor, NULL);
     _glfwRestoreVideoModeX11(window->monitor);
 
     _glfw.x11.saver.count--;
@@ -1335,14 +1344,14 @@ static void processEvent(XEvent *event)
                 if (state == IconicState)
                 {
                     if (window->monitor)
-                        leaveFullscreenMode(window);
+                        releaseMonitor(window);
 
                     _glfwInputWindowIconify(window, GLFW_TRUE);
                 }
                 else if (state == NormalState)
                 {
                     if (window->monitor)
-                        enterFullscreenMode(window);
+                        acquireMonitor(window);
 
                     _glfwInputWindowIconify(window, GLFW_FALSE);
                 }
@@ -1450,7 +1459,8 @@ int _glfwPlatformCreateWindow(_GLFWwindow* window,
     if (window->monitor)
     {
         _glfwPlatformShowWindow(window);
-        enterFullscreenMode(window);
+        if (!acquireMonitor(window))
+            return GLFW_FALSE;
     }
 
     return GLFW_TRUE;
@@ -1459,7 +1469,7 @@ int _glfwPlatformCreateWindow(_GLFWwindow* window,
 void _glfwPlatformDestroyWindow(_GLFWwindow* window)
 {
     if (window->monitor)
-        leaveFullscreenMode(window);
+        releaseMonitor(window);
 
     if (window->x11.ic)
     {