Support additional screen layouts.

Allows users to choose a single screen layout or a large screen layout.
Adds a configuration option to change the prominent screen.

src/citra/config.cpp

@@ -72,6 +72,10 @@ void Config::ReadValues() {
     Settings::values.bg_green = (float)sdl2_config->GetReal("Renderer", "bg_green", 1.0);
     Settings::values.bg_blue = (float)sdl2_config->GetReal("Renderer", "bg_blue", 1.0);
 
+    // Layout
+    Settings::values.layout_option = static_cast<Settings::LayoutOption>(sdl2_config->GetInteger("Layout", "layout_option", 0));
+    Settings::values.swap_screen = sdl2_config->GetBoolean("Layout", "swap_screen", false);
+
     // Audio
     Settings::values.sink_id = sdl2_config->Get("Audio", "output_engine", "auto");
     Settings::values.enable_audio_stretching =

src/citra/default_ini.h

@@ -63,6 +63,16 @@ use_scaled_resolution =
 # 0 (default): Off, 1: On
 use_vsync =
 
+[Layout]
+# Layout for the screen inside the render window.
+# 0 (default): Default Top Bottom Screen, 1: Single Screen Only, 2: Large Screen Small Screen
+layout_option =
+
+# Swaps the prominent screen with the other screen.
+# For example, if Single Screen is chosen, setting this to 1 will display the bottom screen instead of the top screen.
+# 0 (default): Top Screen is prominent, 1: Bottom Screen is prominent
+swap_screen =
+
 # The clear color for the renderer. What shows up on the sides of the bottom screen.
 # Must be in range of 0.0-1.0. Defaults to 1.0 for all.
 bg_red =

src/citra/emu_window/emu_window_sdl2.cpp

@@ -46,11 +46,8 @@ bool EmuWindow_SDL2::IsOpen() const {
 
 void EmuWindow_SDL2::OnResize() {
     int width, height;
-
     SDL_GetWindowSize(render_window, &width, &height);
-
-    NotifyFramebufferLayoutChanged(
-        EmuWindow::FramebufferLayout::DefaultScreenLayout(width, height));
+    UpdateCurrentFramebufferLayout(width, height);
 }
 
 EmuWindow_SDL2::EmuWindow_SDL2() {

src/citra_qt/bootmanager.cpp

@@ -161,9 +161,7 @@ void GRenderWindow::OnFramebufferSizeChanged() {
     qreal pixelRatio = windowPixelRatio();
     unsigned width = child->QPaintDevice::width() * pixelRatio;
     unsigned height = child->QPaintDevice::height() * pixelRatio;
-
-    NotifyFramebufferLayoutChanged(
-        EmuWindow::FramebufferLayout::DefaultScreenLayout(width, height));
+    UpdateCurrentFramebufferLayout(width, height);
 }
 
 void GRenderWindow::BackupGeometry() {

src/citra_qt/config.cpp

@@ -54,6 +54,11 @@ void Config::ReadValues() {
     Settings::values.bg_blue = qt_config->value("bg_blue", 1.0).toFloat();
     qt_config->endGroup();
 
+    qt_config->beginGroup("Layout");
+    Settings::values.layout_option = static_cast<Settings::LayoutOption>(qt_config->value("layout_option").toInt());
+    Settings::values.swap_screen = qt_config->value("swap_screen", false).toBool();
+    qt_config->endGroup();
+
     qt_config->beginGroup("Audio");
     Settings::values.sink_id = qt_config->value("output_engine", "auto").toString().toStdString();
     Settings::values.enable_audio_stretching =
@@ -155,6 +160,11 @@ void Config::SaveValues() {
     qt_config->setValue("bg_blue", (double)Settings::values.bg_blue);
     qt_config->endGroup();
 
+    qt_config->beginGroup("Layout");
+    qt_config->setValue("layout_option", static_cast<int>(Settings::values.layout_option));
+    qt_config->setValue("swap_screen", Settings::values.swap_screen);
+    qt_config->endGroup();
+
     qt_config->beginGroup("Audio");
     qt_config->setValue("output_engine", QString::fromStdString(Settings::values.sink_id));
     qt_config->setValue("enable_audio_stretching", Settings::values.enable_audio_stretching);

src/citra_qt/configure_dialog.cpp

@@ -23,4 +23,5 @@ void ConfigureDialog::applyConfiguration() {
     ui->graphicsTab->applyConfiguration();
     ui->audioTab->applyConfiguration();
     ui->debugTab->applyConfiguration();
+    Settings::Apply();
 }

src/citra_qt/configure_graphics.cpp

@@ -23,6 +23,8 @@ void ConfigureGraphics::setConfiguration() {
     ui->toggle_shader_jit->setChecked(Settings::values.use_shader_jit);
     ui->toggle_scaled_resolution->setChecked(Settings::values.use_scaled_resolution);
     ui->toggle_vsync->setChecked(Settings::values.use_vsync);
+    ui->layout_combobox->setCurrentIndex(static_cast<int>(Settings::values.layout_option));
+    ui->swap_screen->setChecked(Settings::values.swap_screen);
 }
 
 void ConfigureGraphics::applyConfiguration() {
@@ -30,5 +32,7 @@ void ConfigureGraphics::applyConfiguration() {
     Settings::values.use_shader_jit = ui->toggle_shader_jit->isChecked();
     Settings::values.use_scaled_resolution = ui->toggle_scaled_resolution->isChecked();
     Settings::values.use_vsync = ui->toggle_vsync->isChecked();
+    Settings::values.layout_option = static_cast<Settings::LayoutOption>(ui->layout_combobox->currentIndex());
+    Settings::values.swap_screen = ui->swap_screen->isChecked();
     Settings::Apply();
 }

src/citra_qt/configure_graphics.ui

@@ -22,39 +22,89 @@
         <string>Graphics</string>
        </property>
        <layout class="QVBoxLayout" name="verticalLayout_2">
-         <item>
-           <widget class="QCheckBox" name="toggle_hw_renderer">
-             <property name="text">
-               <string>Enable hardware renderer</string>
-             </property>
-           </widget>
-         </item>
-         <item>
-           <widget class="QCheckBox" name="toggle_shader_jit">
-             <property name="text">
-               <string>Enable shader JIT</string>
-             </property>
-           </widget>
-         </item>
-         <item>
-           <widget class="QCheckBox" name="toggle_scaled_resolution">
-             <property name="text">
-               <string>Enable scaled resolution</string>
-             </property>
-           </widget>
-         </item>
-         <item>
-           <widget class="QCheckBox" name="toggle_vsync">
-             <property name="text">
-               <string>Enable V-Sync</string>
-             </property>
-           </widget>
-         </item>
+        <item>
+         <widget class="QCheckBox" name="toggle_hw_renderer">
+          <property name="text">
+           <string>Enable hardware renderer</string>
+          </property>
+         </widget>
+        </item>
+        <item>
+         <widget class="QCheckBox" name="toggle_shader_jit">
+          <property name="text">
+           <string>Enable shader JIT</string>
+          </property>
+         </widget>
+        </item>
+        <item>
+         <widget class="QCheckBox" name="toggle_scaled_resolution">
+          <property name="text">
+           <string>Enable scaled resolution</string>
+          </property>
+         </widget>
+        </item>
+        <item>
+         <widget class="QCheckBox" name="toggle_vsync">
+          <property name="text">
+           <string>Enable V-Sync</string>
+          </property>
+         </widget>
+        </item>
        </layout>
       </widget>
      </item>
     </layout>
    </item>
+   <item>
+    <widget class="QGroupBox" name="groupBox2">
+     <property name="title">
+      <string>Layout</string>
+     </property>
+     <layout class="QHBoxLayout" name="horizontalLayout_3">
+      <item>
+       <layout class="QVBoxLayout" name="verticalLayout_2">
+        <item>
+         <layout class="QHBoxLayout" name="horizontalLayout_3">
+          <item>
+           <widget class="QLabel" name="label1">
+            <property name="text">
+             <string>Screen Layout:</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <widget class="QComboBox" name="layout_combobox">
+            <item>
+             <property name="text">
+              <string notr="true">Default</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string notr="true">Single Screen</string>
+             </property>
+            </item>
+            <item>
+             <property name="text">
+              <string notr="true">Large Screen</string>
+             </property>
+            </item>
+           </widget>
+          </item>
+         </layout>
+        </item>
+        <item>
+         <widget class="QCheckBox" name="swap_screen">
+          <property name="text">
+           <string>Swap Screens</string>
+          </property>
+         </widget>
+        </item>
+       </layout>
+      </item>
+     </layout>
+    </widget>
+   </item>
    <item>
     <spacer name="verticalSpacer">
      <property name="orientation">
@@ -71,22 +121,5 @@
   </layout>
  </widget>
  <resources/>
- <connections>
-  <connection>
-   <sender>toggle_gdbstub</sender>
-   <signal>toggled(bool)</signal>
-   <receiver>gdbport_spinbox</receiver>
-   <slot>setEnabled(bool)</slot>
-   <hints>
-    <hint type="sourcelabel">
-     <x>84</x>
-     <y>157</y>
-    </hint>
-    <hint type="destinationlabel">
-     <x>342</x>
-     <y>158</y>
-    </hint>
-   </hints>
-  </connection>
- </connections>
+ <connections/>
 </ui>

src/common/CMakeLists.txt

@@ -5,6 +5,7 @@ set(SRCS
             break_points.cpp
             emu_window.cpp
             file_util.cpp
+            framebuffer_layout.cpp
             hash.cpp
             key_map.cpp
             logging/filter.cpp
@@ -35,6 +36,7 @@ set(HEADERS
             common_types.h
             emu_window.h
             file_util.h
+            framebuffer_layout.h
             hash.h
             key_map.h
             linear_disk_cache.h

src/common/emu_window.cpp

@@ -40,7 +40,7 @@ void EmuWindow::CirclePadUpdated(float x, float y) {
  * @param framebuffer_y Framebuffer y-coordinate to check
  * @return True if the coordinates are within the touchpad, otherwise false
  */
-static bool IsWithinTouchscreen(const EmuWindow::FramebufferLayout& layout, unsigned framebuffer_x,
+static bool IsWithinTouchscreen(const Layout::FramebufferLayout& layout, unsigned framebuffer_x,
                                 unsigned framebuffer_y) {
     return (
         framebuffer_y >= layout.bottom_screen.top && framebuffer_y < layout.bottom_screen.bottom &&
@@ -89,57 +89,19 @@ void EmuWindow::TouchMoved(unsigned framebuffer_x, unsigned framebuffer_y) {
     TouchPressed(framebuffer_x, framebuffer_y);
 }
 
-EmuWindow::FramebufferLayout EmuWindow::FramebufferLayout::DefaultScreenLayout(unsigned width,
-                                                                               unsigned height) {
-    // When hiding the widget, the function receives a size of 0
-    if (width == 0)
-        width = 1;
-    if (height == 0)
-        height = 1;
-
-    EmuWindow::FramebufferLayout res = {width, height, {}, {}};
-
-    float window_aspect_ratio = static_cast<float>(height) / width;
-    float emulation_aspect_ratio =
-        static_cast<float>(VideoCore::kScreenTopHeight * 2) / VideoCore::kScreenTopWidth;
-
-    if (window_aspect_ratio > emulation_aspect_ratio) {
-        // Window is narrower than the emulation content => apply borders to the top and bottom
-        int viewport_height = static_cast<int>(std::round(emulation_aspect_ratio * width));
-
-        res.top_screen.left = 0;
-        res.top_screen.right = res.top_screen.left + width;
-        res.top_screen.top = (height - viewport_height) / 2;
-        res.top_screen.bottom = res.top_screen.top + viewport_height / 2;
-
-        int bottom_width = static_cast<int>(
-            (static_cast<float>(VideoCore::kScreenBottomWidth) / VideoCore::kScreenTopWidth) *
-            (res.top_screen.right - res.top_screen.left));
-        int bottom_border = ((res.top_screen.right - res.top_screen.left) - bottom_width) / 2;
-
-        res.bottom_screen.left = bottom_border;
-        res.bottom_screen.right = res.bottom_screen.left + bottom_width;
-        res.bottom_screen.top = res.top_screen.bottom;
-        res.bottom_screen.bottom = res.bottom_screen.top + viewport_height / 2;
-    } else {
-        // Otherwise, apply borders to the left and right sides of the window.
-        int viewport_width = static_cast<int>(std::round(height / emulation_aspect_ratio));
-
-        res.top_screen.left = (width - viewport_width) / 2;
-        res.top_screen.right = res.top_screen.left + viewport_width;
-        res.top_screen.top = 0;
-        res.top_screen.bottom = res.top_screen.top + height / 2;
-
-        int bottom_width = static_cast<int>(
-            (static_cast<float>(VideoCore::kScreenBottomWidth) / VideoCore::kScreenTopWidth) *
-            (res.top_screen.right - res.top_screen.left));
-        int bottom_border = ((res.top_screen.right - res.top_screen.left) - bottom_width) / 2;
-
-        res.bottom_screen.left = res.top_screen.left + bottom_border;
-        res.bottom_screen.right = res.bottom_screen.left + bottom_width;
-        res.bottom_screen.top = res.top_screen.bottom;
-        res.bottom_screen.bottom = res.bottom_screen.top + height / 2;
+void EmuWindow::UpdateCurrentFramebufferLayout(unsigned width, unsigned height) {
+    Layout::FramebufferLayout layout;
+    switch (Settings::values.layout_option) {
+    case Settings::LayoutOption::SingleScreen:
+        layout = Layout::SingleFrameLayout(width, height, Settings::values.swap_screen);
+        break;
+    case Settings::LayoutOption::LargeScreen:
+        layout = Layout::LargeFrameLayout(width, height, Settings::values.swap_screen);
+        break;
+    case Settings::LayoutOption::Default:
+    default:
+        layout = Layout::DefaultFrameLayout(width, height, Settings::values.swap_screen);
+        break;
     }
-
-    return res;
+    NotifyFramebufferLayoutChanged(layout);
 }

src/common/emu_window.h

@@ -7,6 +7,7 @@
 #include <tuple>
 #include <utility>
 #include "common/common_types.h"
+#include "common/framebuffer_layout.h"
 #include "common/math_util.h"
 #include "core/hle/service/hid/hid.h"
 
@@ -38,23 +39,6 @@ public:
         std::pair<unsigned, unsigned> min_client_area_size;
     };
 
-    /// Describes the layout of the window framebuffer (size and top/bottom screen positions)
-    struct FramebufferLayout {
-
-        /**
-         * Factory method for constructing a default FramebufferLayout
-         * @param width Window framebuffer width in pixels
-         * @param height Window framebuffer height in pixels
-         * @return Newly created FramebufferLayout object with default screen regions initialized
-         */
-        static FramebufferLayout DefaultScreenLayout(unsigned width, unsigned height);
-
-        unsigned width;
-        unsigned height;
-        MathUtil::Rectangle<unsigned> top_screen;
-        MathUtil::Rectangle<unsigned> bottom_screen;
-    };
-
     /// Swap buffers to display the next frame
     virtual void SwapBuffers() = 0;
 
@@ -211,10 +195,16 @@ public:
       * Gets the framebuffer layout (width, height, and screen regions)
       * @note This method is thread-safe
       */
-    const FramebufferLayout& GetFramebufferLayout() const {
+    const Layout::FramebufferLayout& GetFramebufferLayout() const {
         return framebuffer_layout;
     }
 
+    /**
+     * Convenience method to update the VideoCore EmuWindow
+     * Read from the current settings to determine which layout to use.
+     */
+    void UpdateCurrentFramebufferLayout(unsigned width, unsigned height);
+
 protected:
     EmuWindow() {
         // TODO: Find a better place to set this.
@@ -250,7 +240,7 @@ protected:
      * Update framebuffer layout with the given parameter.
      * @note EmuWindow implementations will usually use this in window resize event handlers.
      */
-    void NotifyFramebufferLayoutChanged(const FramebufferLayout& layout) {
+    void NotifyFramebufferLayoutChanged(const Layout::FramebufferLayout& layout) {
         framebuffer_layout = layout;
     }
 
@@ -274,7 +264,7 @@ private:
         // By default, ignore this request and do nothing.
     }
 
-    FramebufferLayout framebuffer_layout; ///< Current framebuffer layout
+    Layout::FramebufferLayout framebuffer_layout; ///< Current framebuffer layout
 
     unsigned client_area_width;  ///< Current client width, should be set by window impl.
     unsigned client_area_height; ///< Current client height, should be set by window impl.

src/common/framebuffer_layout.cpp

@@ -0,0 +1,312 @@
+// Copyright 2016 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <cmath>
+
+#include "common/assert.h"
+#include "common/framebuffer_layout.h"
+#include "video_core/video_core.h"
+
+namespace Layout {
+static FramebufferLayout DefaultFrameLayout(unsigned width, unsigned height) {
+
+    ASSERT(width > 0);
+    ASSERT(height > 0);
+
+    FramebufferLayout res {width, height, true, true, {}, {}};
+
+    float window_aspect_ratio = static_cast<float>(height) / width;
+    float emulation_aspect_ratio = static_cast<float>(VideoCore::kScreenTopHeight * 2) /
+        VideoCore::kScreenTopWidth;
+
+    if (window_aspect_ratio > emulation_aspect_ratio) {
+        // Window is narrower than the emulation content => apply borders to the top and bottom
+        int viewport_height = static_cast<int>(std::round(emulation_aspect_ratio * width));
+
+        res.top_screen.left = 0;
+        res.top_screen.right = res.top_screen.left + width;
+        res.top_screen.top = (height - viewport_height) / 2;
+        res.top_screen.bottom = res.top_screen.top + viewport_height / 2;
+
+        int bottom_width = static_cast<int>((static_cast<float>(VideoCore::kScreenBottomWidth) /
+            VideoCore::kScreenTopWidth) * (res.top_screen.right - res.top_screen.left));
+        int bottom_border = ((res.top_screen.right - res.top_screen.left) - bottom_width) / 2;
+
+        res.bottom_screen.left = bottom_border;
+        res.bottom_screen.right = res.bottom_screen.left + bottom_width;
+        res.bottom_screen.top = res.top_screen.bottom;
+        res.bottom_screen.bottom = res.bottom_screen.top + viewport_height / 2;
+    } else {
+        // Otherwise, apply borders to the left and right sides of the window.
+        int viewport_width = static_cast<int>(std::round(height / emulation_aspect_ratio));
+
+        res.top_screen.left = (width - viewport_width) / 2;
+        res.top_screen.right = res.top_screen.left + viewport_width;
+        res.top_screen.top = 0;
+        res.top_screen.bottom = res.top_screen.top + height / 2;
+
+        int bottom_width = static_cast<int>((static_cast<float>(VideoCore::kScreenBottomWidth) /
+            VideoCore::kScreenTopWidth) * (res.top_screen.right - res.top_screen.left));
+        int bottom_border = ((res.top_screen.right - res.top_screen.left) - bottom_width) / 2;
+
+        res.bottom_screen.left = res.top_screen.left + bottom_border;
+        res.bottom_screen.right = res.bottom_screen.left + bottom_width;
+        res.bottom_screen.top = res.top_screen.bottom;
+        res.bottom_screen.bottom = res.bottom_screen.top + height / 2;
+    }
+
+    return res;
+}
+
+static FramebufferLayout DefaultFrameLayout_Swapped(unsigned width, unsigned height) {
+
+    ASSERT(width > 0);
+    ASSERT(height > 0);
+
+    FramebufferLayout res {width, height, true, true, {}, {}};
+
+    float window_aspect_ratio = static_cast<float>(height) / width;
+    float emulation_aspect_ratio = static_cast<float>(VideoCore::kScreenTopHeight * 2) /
+        VideoCore::kScreenTopWidth;
+
+    if (window_aspect_ratio > emulation_aspect_ratio) {
+        // Window is narrower than the emulation content => apply borders to the top and bottom
+        int viewport_height = static_cast<int>(std::round(emulation_aspect_ratio * width));
+
+        res.top_screen.left = 0;
+        res.top_screen.right = res.top_screen.left + width;
+
+        int bottom_width = static_cast<int>((static_cast<float>(VideoCore::kScreenBottomWidth) /
+            VideoCore::kScreenTopWidth) * (res.top_screen.right - res.top_screen.left));
+        int bottom_border = ((res.top_screen.right - res.top_screen.left) - bottom_width) / 2;
+
+        res.bottom_screen.left = bottom_border;
+        res.bottom_screen.right = res.bottom_screen.left + bottom_width;
+        res.bottom_screen.top = (height - viewport_height) / 2;
+        res.bottom_screen.bottom = res.bottom_screen.top + viewport_height / 2;
+
+        res.top_screen.top = res.bottom_screen.bottom;
+        res.top_screen.bottom = res.top_screen.top + viewport_height / 2;
+    } else {
+        // Otherwise, apply borders to the left and right sides of the window.
+        int viewport_width = static_cast<int>(std::round(height / emulation_aspect_ratio));
+        res.top_screen.left = (width - viewport_width) / 2;
+        res.top_screen.right = res.top_screen.left + viewport_width;
+
+        int bottom_width = static_cast<int>((static_cast<float>(VideoCore::kScreenBottomWidth) /
+            VideoCore::kScreenTopWidth) * (res.top_screen.right - res.top_screen.left));
+        int bottom_border = ((res.top_screen.right - res.top_screen.left) - bottom_width) / 2;
+
+        res.bottom_screen.left = res.top_screen.left + bottom_border;
+        res.bottom_screen.right = res.bottom_screen.left + bottom_width;
+        res.bottom_screen.top = 0;
+        res.bottom_screen.bottom = res.bottom_screen.top + height / 2;
+
+        res.top_screen.top = res.bottom_screen.bottom;
+        res.top_screen.bottom = res.top_screen.top + height / 2;
+    }
+
+    return res;
+}
+
+static FramebufferLayout SingleFrameLayout(unsigned width, unsigned height) {
+
+    ASSERT(width > 0);
+    ASSERT(height > 0);
+
+    FramebufferLayout res {width, height, true, false, {}, {}};
+
+    float window_aspect_ratio = static_cast<float>(height) / width;
+    float emulation_aspect_ratio = static_cast<float>(VideoCore::kScreenTopHeight) /
+        VideoCore::kScreenTopWidth;
+
+    if (window_aspect_ratio > emulation_aspect_ratio) {
+        // Window is narrower than the emulation content => apply borders to the top and bottom
+        int viewport_height = static_cast<int>(std::round(emulation_aspect_ratio * width));
+
+        res.top_screen.left = 0;
+        res.top_screen.right = res.top_screen.left + width;
+        res.top_screen.top = (height - viewport_height) / 2;
+        res.top_screen.bottom = res.top_screen.top + viewport_height;
+
+        res.bottom_screen.left = 0;
+        res.bottom_screen.right = VideoCore::kScreenBottomWidth;
+        res.bottom_screen.top = 0;
+        res.bottom_screen.bottom = VideoCore::kScreenBottomHeight;
+    } else {
+        // Otherwise, apply borders to the left and right sides of the window.
+        int viewport_width = static_cast<int>(std::round(height / emulation_aspect_ratio));
+
+        res.top_screen.left = (width - viewport_width) / 2;
+        res.top_screen.right = res.top_screen.left + viewport_width;
+        res.top_screen.top = 0;
+        res.top_screen.bottom = res.top_screen.top + height;
+
+        // The Rasterizer still depends on these fields to maintain the right aspect ratio
+        res.bottom_screen.left = 0;
+        res.bottom_screen.right = VideoCore::kScreenBottomWidth;
+        res.bottom_screen.top = 0;
+        res.bottom_screen.bottom = VideoCore::kScreenBottomHeight;
+    }
+
+    return res;
+}
+
+static FramebufferLayout SingleFrameLayout_Swapped(unsigned width, unsigned height) {
+
+    ASSERT(width > 0);
+    ASSERT(height > 0);
+
+    FramebufferLayout res {width, height, false, true, {}, {}};
+
+    float window_aspect_ratio = static_cast<float>(height) / width;
+    float emulation_aspect_ratio = static_cast<float>(VideoCore::kScreenBottomHeight) /
+        VideoCore::kScreenBottomWidth;
+
+    if (window_aspect_ratio > emulation_aspect_ratio) {
+        // Window is narrower than the emulation content => apply borders to the top and bottom
+        int viewport_height = static_cast<int>(std::round(emulation_aspect_ratio * width));
+
+        res.bottom_screen.left = 0;
+        res.bottom_screen.right = res.bottom_screen.left + width;
+        res.bottom_screen.top = (height - viewport_height) / 2;
+        res.bottom_screen.bottom = res.bottom_screen.top + viewport_height;
+
+        // The Rasterizer still depends on these fields to maintain the right aspect ratio
+        res.top_screen.left = 0;
+        res.top_screen.right = VideoCore::kScreenTopWidth;
+        res.top_screen.top = 0;
+        res.top_screen.bottom = VideoCore::kScreenTopHeight;
+    } else {
+        // Otherwise, apply borders to the left and right sides of the window.
+        int viewport_width = static_cast<int>(std::round(height / emulation_aspect_ratio));
+
+        res.bottom_screen.left = (width - viewport_width) / 2;
+        res.bottom_screen.right = res.bottom_screen.left + viewport_width;
+        res.bottom_screen.top = 0;
+        res.bottom_screen.bottom = res.bottom_screen.top + height;
+
+        res.top_screen.left = 0;
+        res.top_screen.right = VideoCore::kScreenTopWidth;
+        res.top_screen.top = 0;
+        res.top_screen.bottom = VideoCore::kScreenTopHeight;
+    }
+
+    return res;
+}
+
+static FramebufferLayout LargeFrameLayout(unsigned width, unsigned height) {
+
+    ASSERT(width > 0);
+    ASSERT(height > 0);
+
+    FramebufferLayout res {width, height, true, true, {}, {}};
+
+    float window_aspect_ratio = static_cast<float>(height) / width;
+    float emulation_aspect_ratio = static_cast<float>(VideoCore::kScreenTopHeight * 4) /
+        (VideoCore::kScreenTopWidth * 4 + VideoCore::kScreenBottomWidth);
+
+    if (window_aspect_ratio > emulation_aspect_ratio) {
+        // Window is narrower than the emulation content => apply borders to the top and bottom
+        int viewport_height = static_cast<int>(std::round(emulation_aspect_ratio * width));
+
+        res.top_screen.left = 0;
+        // Top screen occupies 4 / 5ths of the total width
+        res.top_screen.right = static_cast<int>(std::round(width / 5)) * 4;
+        res.top_screen.top = (height - viewport_height) / 2;
+        res.top_screen.bottom = res.top_screen.top + viewport_height;
+
+        int bottom_height = static_cast<int>((static_cast<float>(VideoCore::kScreenBottomHeight) /
+            VideoCore::kScreenBottomWidth) * (width - res.top_screen.right));
+
+        res.bottom_screen.left = res.top_screen.right;
+        res.bottom_screen.right = width;
+        res.bottom_screen.bottom = res.top_screen.bottom;
+        res.bottom_screen.top = res.bottom_screen.bottom - bottom_height;
+    } else {
+        // Otherwise, apply borders to the left and right sides of the window.
+        int viewport_width = static_cast<int>(std::round(height / emulation_aspect_ratio));
+        // Break the viewport into fifths and give top 4 of them
+        int fifth_width = static_cast<int>(std::round(viewport_width / 5));
+
+        res.top_screen.left = (width - viewport_width) / 2;
+        res.top_screen.right = res.top_screen.left + fifth_width * 4;
+        res.top_screen.top = 0;
+        res.top_screen.bottom = height;
+
+        int bottom_height = static_cast<int>((static_cast<float>(VideoCore::kScreenBottomHeight) /
+            VideoCore::kScreenBottomWidth) * (fifth_width));
+
+        res.bottom_screen.left = res.top_screen.right;
+        res.bottom_screen.right = width - (width - viewport_width) / 2;
+        res.bottom_screen.bottom = res.top_screen.bottom;
+        res.bottom_screen.top = res.bottom_screen.bottom - bottom_height;
+    }
+
+    return res;
+}
+
+static FramebufferLayout LargeFrameLayout_Swapped(unsigned width, unsigned height) {
+
+    ASSERT(width > 0);
+    ASSERT(height > 0);
+
+    FramebufferLayout res {width, height, true, true, {}, {}};
+
+    float window_aspect_ratio = static_cast<float>(height) / width;
+    float emulation_aspect_ratio = static_cast<float>(VideoCore::kScreenBottomHeight * 4) /
+        (VideoCore::kScreenBottomWidth * 4 + VideoCore::kScreenTopWidth);
+
+    if (window_aspect_ratio > emulation_aspect_ratio) {
+        // Window is narrower than the emulation content => apply borders to the top and bottom
+        int viewport_height = static_cast<int>(std::round(emulation_aspect_ratio * width));
+
+        res.bottom_screen.left = 0;
+        // Top screen occupies 4 / 5ths of the total width
+        res.bottom_screen.right = static_cast<int>(std::round(width / 5)) * 4;
+        res.bottom_screen.top = (height - viewport_height) / 2;
+        res.bottom_screen.bottom = res.bottom_screen.top + viewport_height;
+
+        int top_height = static_cast<int>((static_cast<float>(VideoCore::kScreenTopHeight) /
+            VideoCore::kScreenTopWidth) * (width - res.bottom_screen.right));
+
+        res.top_screen.left = res.bottom_screen.right;
+        res.top_screen.right = width;
+        res.top_screen.bottom = res.bottom_screen.bottom;
+        res.top_screen.top = res.top_screen.bottom - top_height;
+    } else {
+        // Otherwise, apply borders to the left and right sides of the window.
+        int viewport_width = static_cast<int>(std::round(height / emulation_aspect_ratio));
+        // Break the viewport into fifths and give top 4 of them
+        int fifth_width = static_cast<int>(std::round(viewport_width / 5));
+
+        res.bottom_screen.left = (width - viewport_width) / 2;
+        res.bottom_screen.right = res.bottom_screen.left + fifth_width * 4;
+        res.bottom_screen.top = 0;
+        res.bottom_screen.bottom = height;
+
+        int top_height = static_cast<int>((static_cast<float>(VideoCore::kScreenTopHeight) /
+            VideoCore::kScreenTopWidth) * (fifth_width));
+
+        res.top_screen.left = res.bottom_screen.right;
+        res.top_screen.right = width - (width - viewport_width) / 2;
+        res.top_screen.bottom = res.bottom_screen.bottom;
+        res.top_screen.top = res.top_screen.bottom - top_height;
+    }
+
+    return res;
+}
+
+FramebufferLayout DefaultFrameLayout(unsigned width, unsigned height, bool is_swapped) {
+    return is_swapped ? DefaultFrameLayout_Swapped(width, height) : DefaultFrameLayout(width, height);
+}
+
+FramebufferLayout SingleFrameLayout(unsigned width, unsigned height, bool is_swapped) {
+    return is_swapped ? SingleFrameLayout_Swapped(width, height) : SingleFrameLayout(width, height);
+}
+
+FramebufferLayout LargeFrameLayout(unsigned width, unsigned height, bool is_swapped) {
+    return is_swapped ? LargeFrameLayout_Swapped(width, height) : LargeFrameLayout(width, height);
+}
+}

src/common/framebuffer_layout.h

@@ -0,0 +1,43 @@
+// Copyright 2016 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include "common/math_util.h"
+namespace Layout {
+/// Describes the layout of the window framebuffer (size and top/bottom screen positions)
+struct FramebufferLayout {
+    unsigned width;
+    unsigned height;
+    bool top_screen_enabled;
+    bool bottom_screen_enabled;
+    MathUtil::Rectangle<unsigned> top_screen;
+    MathUtil::Rectangle<unsigned> bottom_screen;
+};
+
+/**
+ * Factory method for constructing a default FramebufferLayout
+ * @param width Window framebuffer width in pixels
+ * @param height Window framebuffer height in pixels
+ * @return Newly created FramebufferLayout object with default screen regions initialized
+ */
+FramebufferLayout DefaultFrameLayout(unsigned width, unsigned height, bool is_swapped);
+
+/**
+ * Factory method for constructing a FramebufferLayout with only the top screen
+ * @param width Window framebuffer width in pixels
+ * @param height Window framebuffer height in pixels
+ * @return Newly created FramebufferLayout object with default screen regions initialized
+ */
+FramebufferLayout SingleFrameLayout(unsigned width, unsigned height, bool is_swapped);
+
+/**
+ * Factory method for constructing a Frame with the a 4x size Top screen with a 1x size bottom screen on the right
+ * This is useful in particular because it matches well with a 1920x1080 resolution monitor
+ * @param width Window framebuffer width in pixels
+ * @param height Window framebuffer height in pixels
+ * @return Newly created FramebufferLayout object with default screen regions initialized
+ */
+FramebufferLayout LargeFrameLayout(unsigned width, unsigned height, bool is_swapped);
+}

src/core/settings.cpp

@@ -7,6 +7,8 @@
 #include "settings.h"
 #include "video_core/video_core.h"
 
+#include "common/emu_window.h"
+
 namespace Settings {
 
 Values values = {};
@@ -20,6 +22,11 @@ void Apply() {
     VideoCore::g_shader_jit_enabled = values.use_shader_jit;
     VideoCore::g_scaled_resolution_enabled = values.use_scaled_resolution;
 
+    if (VideoCore::g_emu_window) {
+        auto layout = VideoCore::g_emu_window->GetFramebufferLayout();
+        VideoCore::g_emu_window->UpdateCurrentFramebufferLayout(layout.width, layout.height);
+    }
+
     AudioCore::SelectSink(values.sink_id);
     AudioCore::EnableStretching(values.enable_audio_stretching);
 }

src/core/settings.h

@@ -10,7 +10,15 @@
 
 namespace Settings {
 
+enum class LayoutOption {
+    Default,
+    SingleScreen,
+    LargeScreen,
+    Custom,
+};
+
 namespace NativeInput {
+
 enum Values {
     // directly mapped keys
     A,
@@ -84,6 +92,9 @@ struct Values {
     bool use_scaled_resolution;
     bool use_vsync;
 
+    LayoutOption layout_option;
+    bool swap_screen;
+
     float bg_red;
     float bg_green;
     float bg_blue;

src/video_core/renderer_opengl/renderer_opengl.cpp

@@ -390,6 +390,8 @@ void RendererOpenGL::DrawSingleScreenRotated(const ScreenInfo& screen_info, floa
  */
 void RendererOpenGL::DrawScreens() {
     auto layout = render_window->GetFramebufferLayout();
+    const auto& top_screen = layout.top_screen;
+    const auto& bottom_screen = layout.bottom_screen;
 
     glViewport(0, 0, layout.width, layout.height);
     glClear(GL_COLOR_BUFFER_BIT);
@@ -403,12 +405,16 @@ void RendererOpenGL::DrawScreens() {
     glActiveTexture(GL_TEXTURE0);
     glUniform1i(uniform_color_texture, 0);
 
-    DrawSingleScreenRotated(screen_infos[0], (float)layout.top_screen.left,
-                            (float)layout.top_screen.top, (float)layout.top_screen.GetWidth(),
-                            (float)layout.top_screen.GetHeight());
-    DrawSingleScreenRotated(screen_infos[1], (float)layout.bottom_screen.left,
-                            (float)layout.bottom_screen.top, (float)layout.bottom_screen.GetWidth(),
-                            (float)layout.bottom_screen.GetHeight());
+    if (layout.top_screen_enabled) {
+        DrawSingleScreenRotated(screen_infos[0], (float)top_screen.left,
+                                (float)top_screen.top, (float)top_screen.GetWidth(),
+                                (float)top_screen.GetHeight());
+    }
+    if (layout.bottom_screen_enabled) {
+        DrawSingleScreenRotated(screen_infos[1], (float)bottom_screen.left,
+                                (float)bottom_screen.top, (float)bottom_screen.GetWidth(),
+                                (float)bottom_screen.GetHeight());
+    }
 
     m_current_frame++;
 }