1 files changed, 50 insertions, 0 deletions
diff --git a/src/common/emu_window.cpp b/src/common/emu_window.cpp
index 48bb35db5..1082ae26d 100644
--- a/src/common/emu_window.cpp
+++ b/src/common/emu_window.cpp
@@ -3,6 +3,7 @@
 // Refer to the license.txt file included.
 
 #include "emu_window.h"
+#include "video_core/video_core.h"
 
 void EmuWindow::KeyPressed(KeyMap::HostDeviceKey key) {
     Service::HID::PadState mapped_key = KeyMap::GetPadKey(key);
@@ -15,3 +16,52 @@ void EmuWindow::KeyReleased(KeyMap::HostDeviceKey key) {
 
     Service::HID::PadButtonRelease(mapped_key);
 }
+
+EmuWindow::FramebufferLayout EmuWindow::FramebufferLayout::DefaultScreenLayout(int width, int height) {
+    ASSERT(width > 0);
+    ASSERT(height > 0);
+
+    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;
+    }
+
+    return res;
+}