[qt] fix aspect ratio enum mismatch for framebuffer (#2792)

the framebuffer:
```c++
enum class AspectRatio {
    Default,
    R4_3,
    R21_9,
    R16_10,
    StretchToWindow,
};
```
the actual enum
```c++
ENUM(AspectRatio, R16_9, R4_3, R21_9, R16_10, Stretch);
```
If someone were to add a new setting it would likely cause catastrophe.

1280/720 = 16/9

Signed-off-by: lizzie <lizzie@eden-emu.dev>

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/2792
Reviewed-by: MaranBr <maranbr@eden-emu.dev>
Reviewed-by: crueter <crueter@eden-emu.dev>
Co-authored-by: lizzie <lizzie@eden-emu.dev>
Co-committed-by: lizzie <lizzie@eden-emu.dev>

2 files changed, 42 insertions, 77 deletions

diff --git a/src/core/frontend/framebuffer_layout.cpp b/src/core/frontend/framebuffer_layout.cpp
index 63e17f9ceb..cd7b5b3046 100644
--- a/src/core/frontend/framebuffer_layout.cpp
+++ b/src/core/frontend/framebuffer_layout.cpp
@@ -14,69 +14,54 @@
 namespace Layout {
 
 // Finds the largest size subrectangle contained in window area that is confined to the aspect ratio
-template <class T>
-static Common::Rectangle<T> MaxRectangle(Common::Rectangle<T> window_area,
-                                         float screen_aspect_ratio) {
-    const float scale = (std::min)(static_cast<float>(window_area.GetWidth()),
-                                 static_cast<float>(window_area.GetHeight()) / screen_aspect_ratio);
-    return Common::Rectangle<T>{0, 0, static_cast<T>(std::round(scale)),
-                                static_cast<T>(std::round(scale * screen_aspect_ratio))};
+static Common::Rectangle<u32> MaxRectangle(Common::Rectangle<u32> window_area, float screen_aspect_ratio) noexcept {
+    const float scale = (std::min)(float(window_area.GetWidth()), float(window_area.GetHeight()) / screen_aspect_ratio);
+    return Common::Rectangle<u32>{0, 0, u32(std::round(scale)), u32(std::round(scale * screen_aspect_ratio))};
 }
 
-FramebufferLayout DefaultFrameLayout(u32 width, u32 height) {
-    ASSERT(width > 0);
-    ASSERT(height > 0);
+/// @brief 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(u32 width, u32 height) noexcept {
+    ASSERT(width > 0 && height > 0);
+    auto const window_aspect_ratio = float(height) / float(width);
+    auto const emulation_aspect_ratio = EmulationAspectRatio(Settings::values.aspect_ratio.GetValue(), window_aspect_ratio);
+    Common::Rectangle<u32> const screen_window_area{0, 0, width, height};
+    auto screen = MaxRectangle(screen_window_area, emulation_aspect_ratio);
+    if (window_aspect_ratio < emulation_aspect_ratio) {
+        screen = screen.TranslateX((screen_window_area.GetWidth() - screen.GetWidth()) / 2);
+    } else {
+        screen = screen.TranslateY((height - screen.GetHeight()) / 2);
+    }
     // The drawing code needs at least somewhat valid values for both screens
     // so just calculate them both even if the other isn't showing.
-    FramebufferLayout res{
+    return FramebufferLayout{
         .width = width,
         .height = height,
-        .screen = {},
+        .screen = screen,
         .is_srgb = false,
     };
-
-    const float window_aspect_ratio = static_cast<float>(height) / static_cast<float>(width);
-    const float emulation_aspect_ratio = EmulationAspectRatio(
-        static_cast<AspectRatio>(Settings::values.aspect_ratio.GetValue()), window_aspect_ratio);
-
-    const Common::Rectangle<u32> screen_window_area{0, 0, width, height};
-    Common::Rectangle<u32> screen = MaxRectangle(screen_window_area, emulation_aspect_ratio);
-
-    if (window_aspect_ratio < emulation_aspect_ratio) {
-        screen = screen.TranslateX((screen_window_area.GetWidth() - screen.GetWidth()) / 2);
-    } else {
-        screen = screen.TranslateY((height - screen.GetHeight()) / 2);
-    }
-
-    res.screen = screen;
-    return res;
-}
-
-FramebufferLayout FrameLayoutFromResolutionScale(f32 res_scale) {
-    const bool is_docked = Settings::IsDockedMode();
-    const u32 screen_width = is_docked ? ScreenDocked::Width : ScreenUndocked::Width;
-    const u32 screen_height = is_docked ? ScreenDocked::Height : ScreenUndocked::Height;
-
-    const u32 width = static_cast<u32>(static_cast<f32>(screen_width) * res_scale);
-    const u32 height = static_cast<u32>(static_cast<f32>(screen_height) * res_scale);
-
-    return DefaultFrameLayout(width, height);
 }
 
-float EmulationAspectRatio(AspectRatio aspect, float window_aspect_ratio) {
+/// @brief Convenience method to determine emulation aspect ratio
+/// @param aspect Represents the index of aspect ratio stored in Settings::values.aspect_ratio
+/// @param window_aspect_ratio Current window aspect ratio
+/// @return Emulation render window aspect ratio
+float EmulationAspectRatio(Settings::AspectRatio aspect, float window_aspect_ratio) noexcept {
     switch (aspect) {
-    case AspectRatio::Default:
-        return static_cast<float>(ScreenUndocked::Height) / ScreenUndocked::Width;
-    case AspectRatio::R4_3:
+    case Settings::AspectRatio::R16_9:
+        return 9.0f / 16.0f;
+    case Settings::AspectRatio::R4_3:
         return 3.0f / 4.0f;
-    case AspectRatio::R21_9:
+    case Settings::AspectRatio::R21_9:
         return 9.0f / 21.0f;
-    case AspectRatio::R16_10:
+    case Settings::AspectRatio::R16_10:
         return 10.0f / 16.0f;
-    case AspectRatio::StretchToWindow:
+    case Settings::AspectRatio::Stretch:
         return window_aspect_ratio;
     default:
-        return static_cast<float>(ScreenUndocked::Height) / ScreenUndocked::Width;
+        return float(ScreenUndocked::Height) / ScreenUndocked::Width;
     }
 }
 
diff --git a/src/core/frontend/framebuffer_layout.h b/src/core/frontend/framebuffer_layout.h
index 94683b30f2..06b826775a 100644
--- a/src/core/frontend/framebuffer_layout.h
+++ b/src/core/frontend/framebuffer_layout.h
@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2018 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -6,6 +9,10 @@
 #include "common/common_types.h"
 #include "common/math_util.h"
 
+namespace Settings {
+enum class AspectRatio : u32;
+}
+
 namespace Layout {
 
 namespace MinimumSize {
@@ -23,15 +30,7 @@ constexpr u32 Width = 1920;
 constexpr u32 Height = 1080;
 } // namespace ScreenDocked
 
-enum class AspectRatio {
-    Default,
-    R4_3,
-    R21_9,
-    R16_10,
-    StretchToWindow,
-};
-
-/// Describes the layout of the window framebuffer
+/// @brief Describes the layout of the window framebuffer
 struct FramebufferLayout {
     u32 width{ScreenUndocked::Width};
     u32 height{ScreenUndocked::Height};
@@ -39,26 +38,7 @@ struct FramebufferLayout {
     bool is_srgb{};
 };
 
-/**
- * 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(u32 width, u32 height);
-
-/**
- * Convenience method to get frame layout by resolution scale
- * @param res_scale resolution scale factor
- */
-FramebufferLayout FrameLayoutFromResolutionScale(f32 res_scale);
-
-/**
- * Convenience method to determine emulation aspect ratio
- * @param aspect Represents the index of aspect ratio stored in Settings::values.aspect_ratio
- * @param window_aspect_ratio Current window aspect ratio
- * @return Emulation render window aspect ratio
- */
-float EmulationAspectRatio(AspectRatio aspect, float window_aspect_ratio);
+FramebufferLayout DefaultFrameLayout(u32 width, u32 height) noexcept;
+float EmulationAspectRatio(Settings::AspectRatio aspect, float window_aspect_ratio) noexcept;
 
 } // namespace Layout