Partially revert "Rework window management to fix issues restoring window state between windowed and full-screen"

This exposes all sorts of issues with full-screen transitions on Windows and macOS:
- Loss of proper window decorations when transitioning from full-screen to windowed on Windows
- Improper sizing when transitioning from true full-screen to windowed on macOS

This reverts commit 38396b26919d56dab02e3e06e7791ef9b748bacf.

app/streaming/session.cpp

@@ -449,6 +449,7 @@ Session::Session(NvComputer* computer, NvApp& app, StreamingPreferences *prefere
       m_AudioMuted(false),
       m_DisplayOriginX(0),
       m_DisplayOriginY(0),
+      m_PendingWindowedTransition(false),
       m_UnexpectedTermination(true), // Failure prior to streaming is unexpected
       m_InputHandler(nullptr),
       m_MouseEmulationRefCount(0),
@@ -896,10 +897,12 @@ void Session::getWindowDimensions(int& x, int& y,
                                   int& width, int& height)
 {
     int displayIndex = 0;
+    bool fullScreen;
 
     if (m_Window != nullptr) {
         displayIndex = SDL_GetWindowDisplayIndex(m_Window);
         SDL_assert(displayIndex >= 0);
+        fullScreen = (SDL_GetWindowFlags(m_Window) & SDL_WINDOW_FULLSCREEN);
     }
     // Create our window on the same display that Qt's UI
     // was being displayed on.
@@ -926,19 +929,38 @@ void Session::getWindowDimensions(int& x, int& y,
                             i, SDL_GetError());
             }
         }
+
+        fullScreen = m_IsFullScreen;
     }
 
     SDL_Rect usableBounds;
-    if (SDL_GetDisplayUsableBounds(displayIndex, &usableBounds) == 0) {
+    if (fullScreen && SDL_GetDisplayBounds(displayIndex, &usableBounds) == 0) {
-        // Don't use more than 80% of the display to leave room for system UI
+        width = usableBounds.w;
-        width = (int)SDL_roundf(usableBounds.w * 0.80f);
+        height = usableBounds.h;
-        height = (int)SDL_roundf(usableBounds.h * 0.80f);
+    }
+    else if (SDL_GetDisplayUsableBounds(displayIndex, &usableBounds) == 0) {
+        width = usableBounds.w;
+        height = usableBounds.h;
 
-        // If the stream window can fit within the usable drawing area with 1:1
+        if (m_Window != nullptr) {
-        // scaling, do that rather than filling the screen.
+            int top, left, bottom, right;
-        if (m_StreamConfig.width < width && m_StreamConfig.height < height) {
+
-            width = m_StreamConfig.width;
+            if (SDL_GetWindowBordersSize(m_Window, &top, &left, &bottom, &right) == 0) {
-            height = m_StreamConfig.height;
+                width -= left + right;
+                height -= top + bottom;
+            }
+            else {
+                SDL_LogWarn(SDL_LOG_CATEGORY_APPLICATION,
+                            "Unable to get window border size: %s",
+                            SDL_GetError());
+            }
+
+            // If the stream window can fit within the usable drawing area with 1:1
+            // scaling, do that rather than filling the screen.
+            if (m_StreamConfig.width < width && m_StreamConfig.height < height) {
+                width = m_StreamConfig.width;
+                height = m_StreamConfig.height;
+            }
         }
     }
     else {
@@ -1048,6 +1070,7 @@ void Session::toggleFullscreen()
             SDL_SetWindowGrab(m_Window, SDL_TRUE);
         }
 
+        SDL_SetWindowResizable(m_Window, SDL_FALSE);
         SDL_SetWindowFullscreen(m_Window, m_FullScreenFlag);
     }
     else {
@@ -1055,6 +1078,10 @@ void Session::toggleFullscreen()
         SDL_SetWindowGrab(m_Window, SDL_FALSE);
 
         SDL_SetWindowFullscreen(m_Window, 0);
+        SDL_SetWindowResizable(m_Window, SDL_TRUE);
+
+        // Reposition the window when the resize is complete
+        m_PendingWindowedTransition = true;
     }
 
     // Input handler might need to start/stop keyboard grab after changing modes
@@ -1351,19 +1378,12 @@ void Session::execInternal()
     SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 8);
     SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, 8);
 
-    Uint32 windowFlags = SDL_WINDOW_ALLOW_HIGHDPI | SDL_WINDOW_RESIZABLE;
-
-    // If the video is larger than the entire desktop, maximize the window
-    if (m_StreamConfig.width > width || m_StreamConfig.height > height) {
-        windowFlags |= SDL_WINDOW_MAXIMIZED;
-    }
-
     m_Window = SDL_CreateWindow("Moonlight",
                                 x,
                                 y,
                                 width,
                                 height,
-                                windowFlags | StreamUtils::getPlatformWindowFlags());
+                                SDL_WINDOW_ALLOW_HIGHDPI | StreamUtils::getPlatformWindowFlags());
     if (!m_Window) {
         SDL_LogWarn(SDL_LOG_CATEGORY_APPLICATION,
                     "SDL_CreateWindow() failed with platform flags: %s",
@@ -1374,7 +1394,7 @@ void Session::execInternal()
                                     y,
                                     width,
                                     height,
-                                    windowFlags);
+                                    SDL_WINDOW_ALLOW_HIGHDPI);
         if (!m_Window) {
             SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
                          "SDL_CreateWindow() failed: %s",
@@ -1411,8 +1431,22 @@ void Session::execInternal()
     }
 #endif
 
-    // Enter full-screen if requested
+    // For non-full screen windows, call getWindowDimensions()
-    if (m_IsFullScreen) {
+    // again after creating a window to allow it to account
+    // for window chrome size.
+    if (!m_IsFullScreen) {
+        getWindowDimensions(x, y, width, height);
+
+        // We must set the size before the position because centering
+        // won't work unless it knows the final size of the window.
+        SDL_SetWindowSize(m_Window, width, height);
+        SDL_SetWindowPosition(m_Window, x, y);
+
+        // Passing SDL_WINDOW_RESIZABLE to set this during window
+        // creation causes our window to be full screen for some reason
+        SDL_SetWindowResizable(m_Window, SDL_TRUE);
+    }
+    else {
         // Update the window display mode based on our current monitor
         updateOptimalWindowDisplayMode();
 
@@ -1582,6 +1616,20 @@ void Session::execInternal()
             }
 #endif
 
+            // Complete any repositioning that was deferred until
+            // the resize from full-screen to windowed had completed.
+            // If we try to do this immediately, the resize won't take effect
+            // properly on Windows.
+            if (m_PendingWindowedTransition) {
+                m_PendingWindowedTransition = false;
+
+                int x, y, width, height;
+                getWindowDimensions(x, y, width, height);
+
+                SDL_SetWindowSize(m_Window, width, height);
+                SDL_SetWindowPosition(m_Window, x, y);
+            }
+
             if (m_FlushingWindowEventsRef > 0) {
                 // Ignore window events for renderer reset if flushing
                 SDL_LogInfo(SDL_LOG_CATEGORY_APPLICATION,

app/streaming/session.h

@@ -163,6 +163,7 @@ private:
     int m_DisplayOriginX;
     int m_DisplayOriginY;
     bool m_ThreadedExec;
+    bool m_PendingWindowedTransition;
     bool m_UnexpectedTermination;
     SdlInputHandler* m_InputHandler;
     int m_MouseEmulationRefCount;