Add default hotkey to swap primary screens.

Also minor style changes

src/common/emu_window.h

@@ -200,7 +200,7 @@ public:
     }
 
     /**
-     * Convenience method to update the VideoCore EmuWindow
+     * Convenience method to update the current frame layout
      * Read from the current settings to determine which layout to use.
      */
     void UpdateCurrentFramebufferLayout(unsigned width, unsigned height);

src/common/framebuffer_layout.cpp

@@ -51,11 +51,15 @@ FramebufferLayout DefaultFrameLayout(unsigned width, unsigned height, bool swapp
             bot_screen.TranslateX((screen_window_area.GetWidth() - bot_screen.GetWidth()) / 2);
     } else {
         // Window is narrower than the emulation content => apply borders to the top and bottom
-        top_screen = top_screen.TranslateY(height / 2 - top_screen.GetHeight());
         // Recalculate the bottom screen to account for the width difference between top and bottom
         screen_window_area = {0, 0, width, top_screen.GetHeight()};
         bot_screen = maxRectangle(screen_window_area, BOT_SCREEN_ASPECT_RATIO);
         bot_screen = bot_screen.TranslateX((top_screen.GetWidth() - bot_screen.GetWidth()) / 2);
+        if (swapped) {
+            bot_screen = bot_screen.TranslateY(height / 2 - bot_screen.GetHeight());
+        } else {
+            top_screen = top_screen.TranslateY(height / 2 - top_screen.GetHeight());
+        }
     }
     // Move the top screen to the bottom if we are swapped.
     res.top_screen = swapped ? top_screen.TranslateY(height / 2) : top_screen;

src/common/framebuffer_layout.h

@@ -33,7 +33,8 @@ FramebufferLayout DefaultFrameLayout(unsigned width, unsigned height, bool is_sw
 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
+ * 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

src/common/math_util.h

@@ -45,10 +45,8 @@ struct Rectangle {
         return Rectangle{left, top + y, right, bottom + y};
     }
     Rectangle<T> Scale(const float s) const {
-        ASSERT(s > 0);
-        return Rectangle {
-            left, top, static_cast<T>((right + left) * s), static_cast<T>((top + bottom) * s)
-        };
+        return Rectangle{left, top, static_cast<T>((right + left) * s),
+                         static_cast<T>((top + bottom) * s)};
     }
 };