UI element resize without canvas recreate. Capture slot by value when loading/saving states.

qt/src/DisplayPanel.cpp

@@ -82,19 +82,19 @@ DisplayPanel::DisplayPanel(EmuApplication *app_)
     });
 
     QObject::connect(comboBox_messages, &QComboBox::currentIndexChanged, [&](int index) {
-        bool restart = (app->config->display_messages == EmuConfig::eOnscreen || index == EmuConfig::eOnscreen);
+        bool recreate = (app->config->display_messages == EmuConfig::eOnscreen || index == EmuConfig::eOnscreen);
 
         app->config->display_messages = index;
         app->updateSettings();
-        if (restart)
-            app->window->recreateCanvas();
+        if (recreate)
+            app->window->recreateUIAssets();
     });
 
     QObject::connect(spinBox_osd_size, &QSpinBox::valueChanged, [&](int value) {
-        bool restart = (app->config->osd_size != value && app->config->display_messages == EmuConfig::eOnscreen);
+        bool recreate = (app->config->osd_size != value && app->config->display_messages == EmuConfig::eOnscreen);
         app->config->osd_size = value;
-        if (restart)
-            app->window->recreateCanvas();
+        if (recreate)
+            app->window->recreateUIAssets();
     });
 }
 

qt/src/EmuApplication.cpp

@@ -460,28 +460,28 @@ void EmuApplication::startInputTimer()
 
 void EmuApplication::loadState(int slot)
 {
-    emu_thread->runOnThread([&] {
+    emu_thread->runOnThread([&, slot] {
         core->loadState(slot);
     });
 }
 
 void EmuApplication::loadState(std::string filename)
 {
-    emu_thread->runOnThread([&] {
+    emu_thread->runOnThread([&, filename] {
         core->loadState(filename);
     });
 }
 
 void EmuApplication::saveState(int slot)
 {
-    emu_thread->runOnThread([&] {
+    emu_thread->runOnThread([&, slot] {
         core->saveState(slot);
     });
 }
 
 void EmuApplication::saveState(std::string filename)
 {
-    emu_thread->runOnThread([&] {
+    emu_thread->runOnThread([&, filename] {
         core->saveState(filename);
     });
 }

qt/src/EmuCanvas.hpp

@@ -14,6 +14,7 @@ class EmuCanvas : public QWidget
     virtual void draw() = 0;
     void paintEvent(QPaintEvent *) override = 0;
     virtual void createContext() {}
+    virtual void recreateUIAssets() {}
     void output(uint8_t *buffer, int width, int height, QImage::Format format, int bytes_per_line, double frame_rate);
     void throttle();
     void resizeEvent(QResizeEvent *event) override = 0;

qt/src/EmuCanvasOpenGL.cpp

@@ -174,11 +174,7 @@ void EmuCanvasOpenGL::createContext()
 
     if (config->display_messages == EmuConfig::eOnscreen)
     {
-        auto defaults = S9xImGuiGetDefaults();
-        defaults.font_size = config->osd_size;
-        defaults.spacing = defaults.font_size / 2.4;
-        S9xImGuiInit(&defaults);
-        ImGui_ImplOpenGL3_Init();
+        recreateUIAssets();
     }
 
     loadShaders();
@@ -383,3 +379,20 @@ void EmuCanvasOpenGL::saveParameters(std::string filename)
     if (shader)
         shader->save(filename.c_str());
 }
+
+void EmuCanvasOpenGL::recreateUIAssets()
+{
+    if (S9xImGuiRunning())
+    {
+        S9xImGuiDeinit();
+    }
+
+    if (config->display_messages != EmuConfig::eOnscreen)
+        return;
+
+    auto defaults = S9xImGuiGetDefaults();
+    defaults.font_size = config->osd_size;
+    defaults.spacing = defaults.font_size / 2.4;
+    S9xImGuiInit(&defaults);
+    ImGui_ImplOpenGL3_Init();
+}

qt/src/EmuCanvasOpenGL.hpp

@@ -23,7 +23,7 @@ class EmuCanvasOpenGL : public EmuCanvas
     void shaderChanged() override;
     void showParametersDialog() override;
     void saveParameters(std::string filename) override;
-
+    void recreateUIAssets() override;
 
   private:
     void resizeTexture(int width, int height);

qt/src/EmuCanvasVulkan.cpp

@@ -300,3 +300,20 @@ void EmuCanvasVulkan::saveParameters(std::string filename)
     if (shader_chain && shader_chain->preset)
         shader_chain->preset->save_to_file(filename);
 }
+
+void EmuCanvasVulkan::recreateUIAssets()
+{
+    if (ImGui::GetCurrentContext())
+    {
+        context->wait_idle();
+        imgui_descriptor_pool.reset();
+        imgui_render_pass.reset();
+        ImGui_ImplVulkan_Shutdown();
+        ImGui::DestroyContext();
+    }
+
+    if (config->display_messages != EmuConfig::eOnscreen)
+        return;
+
+    initImGui();
+}

qt/src/EmuCanvasVulkan.hpp

@@ -30,6 +30,7 @@ class EmuCanvasVulkan : public EmuCanvas
     void draw() override;
 
     bool initImGui();
+    void recreateUIAssets();
     vk::UniqueRenderPass imgui_render_pass;
     vk::UniqueDescriptorPool imgui_descriptor_pool;
 

qt/src/EmuMainWindow.cpp

@@ -633,3 +633,11 @@ void EmuMainWindow::output(uint8_t *buffer, int width, int height, QImage::Forma
     if (canvas)
         canvas->output(buffer, width, height, format, bytes_per_line, frame_rate);
 }
+
+void EmuMainWindow::recreateUIAssets()
+{
+    app->emu_thread->runOnThread([&] {
+        if (canvas)
+            canvas->recreateUIAssets();
+    }, true);
+}

qt/src/EmuMainWindow.hpp

@@ -33,6 +33,7 @@ class EmuMainWindow : public QMainWindow
     bool isActivelyDrawing();
     void openFile();
     bool openFile(std::string filename);
+    void recreateUIAssets();
     std::vector<std::string> getDisplayDeviceList();
     EmuApplication *app;
     EmuCanvas *canvas;