Qt: Allow toggling fullscreen when VM is paused

src/core/host.cpp

@@ -322,7 +322,12 @@ void Host::ResizeDisplayWindow(s32 width, s32 height, float scale)
   if (System::IsValid())
   {
     if (System::IsPaused())
+    {
+      // Hackity hack, on some systems, presenting a single frame isn't enough to actually get it
+      // displayed. Two seems to be good enough. Maybe something to do with direct scanout.
       System::InvalidateDisplay();
+      System::InvalidateDisplay();
+    }
 
     System::HostDisplayResized();
   }

src/duckstation-qt/displaywidget.cpp

@@ -1,14 +1,19 @@
-// SPDX-FileCopyrightText: 2019-2022 Connor McLaughlin <stenzek@gmail.com>
+// SPDX-FileCopyrightText: 2019-2024 Connor McLaughlin <stenzek@gmail.com>
 // SPDX-License-Identifier: (GPL-3.0 OR CC-BY-NC-ND-4.0)
 
 #include "displaywidget.h"
-#include "common/assert.h"
-#include "common/bitutils.h"
-#include "common/log.h"
 #include "mainwindow.h"
 #include "qthost.h"
 #include "qtutils.h"
+
+#include "core/fullscreen_ui.h"
+
 #include "util/imgui_manager.h"
+
+#include "common/assert.h"
+#include "common/bitutils.h"
+#include "common/log.h"
+
 #include <QtCore/QDebug>
 #include <QtGui/QGuiApplication>
 #include <QtGui/QKeyEvent>
@@ -311,9 +316,12 @@ bool DisplayWidget::event(QEvent* event)
 
       // don't toggle fullscreen when we're bound.. that wouldn't end well.
       if (event->type() == QEvent::MouseButtonDblClick &&
-          static_cast<const QMouseEvent*>(event)->button() == Qt::LeftButton &&
-          !InputManager::HasAnyBindingsForKey(InputManager::MakePointerButtonKey(0, 0)) && QtHost::IsSystemValid() &&
-          !QtHost::IsSystemPaused() && Host::GetBoolSettingValue("Main", "DoubleClickTogglesFullscreen", true))
+          static_cast<const QMouseEvent*>(event)->button() == Qt::LeftButton && QtHost::IsSystemValid() &&
+          !FullscreenUI::HasActiveWindow() &&
+          ((!QtHost::IsSystemPaused() &&
+            !InputManager::HasAnyBindingsForKey(InputManager::MakePointerButtonKey(0, 0))) ||
+           (QtHost::IsSystemPaused() && !ImGuiManager::WantsMouseInput())) &&
+          Host::GetBoolSettingValue("Main", "DoubleClickTogglesFullscreen", true))
       {
         g_emu_thread->toggleFullscreen();
       }

src/util/imgui_manager.cpp

@@ -892,6 +892,11 @@ bool ImGuiManager::WantsTextInput()
   return s_imgui_wants_keyboard.load(std::memory_order_acquire);
 }
 
+bool ImGuiManager::WantsMouseInput()
+{
+  return s_imgui_wants_mouse.load(std::memory_order_acquire);
+}
+
 void ImGuiManager::AddTextInput(std::string str)
 {
   if (!ImGui::GetCurrentContext())

src/util/imgui_manager.h

@@ -69,6 +69,9 @@ ImFont* GetLargeFont();
 /// Returns true if imgui wants to intercept text input.
 bool WantsTextInput();
 
+/// Returns true if imgui wants to intercept mouse input.
+bool WantsMouseInput();
+
 /// Called on the UI or CPU thread in response to a key press. String is UTF-8.
 void AddTextInput(std::string str);