Graphics: Adapt aspect ratio when SBS/TAB 3D is used

Adds support for choosing to present the full resolution
independently to each eye when using side-by-side or
top-and-bottom 3D.

8 files changed, 82 insertions, 23 deletions

diff --git a/Source/Core/Core/Config/GraphicsSettings.cpp b/Source/Core/Core/Config/GraphicsSettings.cpp
index 4dfe819beb..cd916c6864 100644
--- a/Source/Core/Core/Config/GraphicsSettings.cpp
+++ b/Source/Core/Core/Config/GraphicsSettings.cpp
@@ -163,6 +163,8 @@ const Info<float> GFX_CC_HDR_PAPER_WHITE_NITS{{System::GFX, "ColorCorrection", "
 // Graphics.Stereoscopy
 
 const Info<StereoMode> GFX_STEREO_MODE{{System::GFX, "Stereoscopy", "StereoMode"}, StereoMode::Off};
+const Info<bool> GFX_STEREO_PER_EYE_RESOLUTION_FULL{
+    {System::GFX, "Stereoscopy", "StereoPerEyeResolutionFull"}, false};
 const Info<int> GFX_STEREO_DEPTH{{System::GFX, "Stereoscopy", "StereoDepth"}, 20};
 const Info<int> GFX_STEREO_CONVERGENCE_PERCENTAGE{
     {System::GFX, "Stereoscopy", "StereoConvergencePercentage"}, 100};
diff --git a/Source/Core/Core/Config/GraphicsSettings.h b/Source/Core/Core/Config/GraphicsSettings.h
index bccc5ae293..7bad7fefbb 100644
--- a/Source/Core/Core/Config/GraphicsSettings.h
+++ b/Source/Core/Core/Config/GraphicsSettings.h
@@ -10,6 +10,7 @@
 enum class AspectMode : int;
 enum class ShaderCompilationMode : int;
 enum class StereoMode : int;
+enum class StereoPerEyeResolution : int;
 enum class TextureFilteringMode : int;
 enum class OutputResamplingMode : int;
 enum class ColorCorrectionRegion : int;
@@ -139,6 +140,7 @@ extern const Info<float> GFX_CC_HDR_PAPER_WHITE_NITS;
 // Graphics.Stereoscopy
 
 extern const Info<StereoMode> GFX_STEREO_MODE;
+extern const Info<bool> GFX_STEREO_PER_EYE_RESOLUTION_FULL;
 extern const Info<int> GFX_STEREO_DEPTH;
 extern const Info<int> GFX_STEREO_CONVERGENCE_PERCENTAGE;
 extern const Info<bool> GFX_STEREO_SWAP_EYES;
diff --git a/Source/Core/Core/DolphinAnalytics.cpp b/Source/Core/Core/DolphinAnalytics.cpp
index 5a5118932b..cc74b4d8af 100644
--- a/Source/Core/Core/DolphinAnalytics.cpp
+++ b/Source/Core/Core/DolphinAnalytics.cpp
@@ -385,6 +385,8 @@ void DolphinAnalytics::MakePerGameBuilder()
   builder.AddData("cfg-gfx-internal-resolution", g_Config.iEFBScale);
   builder.AddData("cfg-gfx-tc-samples", g_Config.iSafeTextureCache_ColorSamples);
   builder.AddData("cfg-gfx-stereo-mode", static_cast<int>(g_Config.stereo_mode));
+  builder.AddData("cfg-gfx-stereo-per-eye-resolution-full",
+                  g_Config.stereo_per_eye_resolution_full);
   builder.AddData("cfg-gfx-hdr", static_cast<int>(g_Config.bHDR));
   builder.AddData("cfg-gfx-per-pixel-lighting", g_Config.bEnablePixelLighting);
   builder.AddData("cfg-gfx-shader-compilation-mode", GetShaderCompilationMode(g_Config));
diff --git a/Source/Core/DolphinQt/Config/Graphics/EnhancementsWidget.cpp b/Source/Core/DolphinQt/Config/Graphics/EnhancementsWidget.cpp
index f70b01ef6a..897eea6be6 100644
--- a/Source/Core/DolphinQt/Config/Graphics/EnhancementsWidget.cpp
+++ b/Source/Core/DolphinQt/Config/Graphics/EnhancementsWidget.cpp
@@ -213,8 +213,12 @@ void EnhancementsWidget::CreateWidgets()
   m_3d_depth = new ConfigSlider(0, Config::GFX_STEREO_DEPTH_MAXIMUM, Config::GFX_STEREO_DEPTH);
   m_3d_convergence = new ConfigSlider(0, Config::GFX_STEREO_CONVERGENCE_MAXIMUM,
                                       Config::GFX_STEREO_CONVERGENCE, 100);
+
   m_3d_swap_eyes = new ConfigBool(tr("Swap Eyes"), Config::GFX_STEREO_SWAP_EYES);
 
+  m_3d_per_eye_resolution =
+      new ConfigBool(tr("Use Full Resolution Per Eye"), Config::GFX_STEREO_PER_EYE_RESOLUTION_FULL);
+
   stereoscopy_layout->addWidget(new QLabel(tr("Stereoscopic 3D Mode:")), 0, 0);
   stereoscopy_layout->addWidget(m_3d_mode, 0, 1);
   stereoscopy_layout->addWidget(new QLabel(tr("Depth:")), 1, 0);
@@ -222,6 +226,11 @@ void EnhancementsWidget::CreateWidgets()
   stereoscopy_layout->addWidget(new QLabel(tr("Convergence:")), 2, 0);
   stereoscopy_layout->addWidget(m_3d_convergence, 2, 1);
   stereoscopy_layout->addWidget(m_3d_swap_eyes, 3, 0);
+  stereoscopy_layout->addWidget(m_3d_per_eye_resolution, 4, 0);
+
+  auto current_stereo_mode = Config::Get(Config::GFX_STEREO_MODE);
+  if (current_stereo_mode != StereoMode::SBS && current_stereo_mode != StereoMode::TAB)
+    m_3d_per_eye_resolution->hide();
 
   main_layout->addWidget(enhancements_box);
   main_layout->addWidget(stereoscopy_box);
@@ -241,9 +250,16 @@ void EnhancementsWidget::ConnectWidgets()
   connect(m_3d_mode, &QComboBox::currentIndexChanged, [this] {
     m_block_save = true;
     m_configure_color_correction->setEnabled(g_Config.backend_info.bSupportsPostProcessing);
-    LoadPPShaders(static_cast<StereoMode>(m_3d_mode->currentIndex()));
-    m_block_save = false;
 
+    auto current_stereo_mode = Config::Get(Config::GFX_STEREO_MODE);
+    LoadPPShaders(current_stereo_mode);
+
+    if (current_stereo_mode == StereoMode::SBS || current_stereo_mode == StereoMode::TAB)
+      m_3d_per_eye_resolution->show();
+    else
+      m_3d_per_eye_resolution->hide();
+
+    m_block_save = false;
     SaveSettings();
   });
   connect(m_configure_color_correction, &QPushButton::clicked, this,
@@ -609,6 +625,10 @@ void EnhancementsWidget::AddDescriptions()
   static const char TR_3D_SWAP_EYES_DESCRIPTION[] = QT_TR_NOOP(
       "Swaps the left and right eye. Most useful in side-by-side stereoscopy "
       "mode.<br><br><dolphin_emphasis>If unsure, leave this unchecked.</dolphin_emphasis>");
+  static const char TR_3D_PER_EYE_RESOLUTION_DESCRIPTION[] =
+      QT_TR_NOOP("Whether each eye gets full or half image resolution when using side-by-side "
+                 "or above-and-below 3D."
+                 "<br><br><dolphin_emphasis>If unsure, leave this unchecked.</dolphin_emphasis>");
   static const char TR_FORCE_24BIT_DESCRIPTION[] = QT_TR_NOOP(
       "Forces the game to render the RGB color channels in 24-bit, thereby increasing "
       "quality by reducing color banding.<br><br>Has no impact on performance and causes "
@@ -679,6 +699,8 @@ void EnhancementsWidget::AddDescriptions()
   m_3d_convergence->SetTitle(tr("Convergence"));
   m_3d_convergence->SetDescription(tr(TR_3D_CONVERGENCE_DESCRIPTION));
 
+  m_3d_per_eye_resolution->SetDescription(tr(TR_3D_PER_EYE_RESOLUTION_DESCRIPTION));
+
   m_3d_swap_eyes->SetDescription(tr(TR_3D_SWAP_EYES_DESCRIPTION));
 }
 
diff --git a/Source/Core/DolphinQt/Config/Graphics/EnhancementsWidget.h b/Source/Core/DolphinQt/Config/Graphics/EnhancementsWidget.h
index 7c4c193fb4..9e64d5400f 100644
--- a/Source/Core/DolphinQt/Config/Graphics/EnhancementsWidget.h
+++ b/Source/Core/DolphinQt/Config/Graphics/EnhancementsWidget.h
@@ -58,6 +58,7 @@ private:
   ConfigSlider* m_3d_depth;
   ConfigSlider* m_3d_convergence;
   ConfigBool* m_3d_swap_eyes;
+  ConfigBool* m_3d_per_eye_resolution;
 
   int m_msaa_modes;
   bool m_block_save;
diff --git a/Source/Core/VideoCommon/Present.cpp b/Source/Core/VideoCommon/Present.cpp
index 66d377acd7..c7ae018bbc 100644
--- a/Source/Core/VideoCommon/Present.cpp
+++ b/Source/Core/VideoCommon/Present.cpp
@@ -398,40 +398,68 @@ Presenter::ConvertStereoRectangle(const MathUtil::Rectangle<int>& rc) const
 float Presenter::CalculateDrawAspectRatio(bool allow_stretch) const
 {
   auto aspect_mode = g_ActiveConfig.aspect_mode;
+  float resulting_aspect_ratio;
 
   if (!allow_stretch && aspect_mode == AspectMode::Stretch)
     aspect_mode = AspectMode::Auto;
 
   // If stretch is enabled, we prefer the aspect ratio of the window.
   if (aspect_mode == AspectMode::Stretch)
-    return (static_cast<float>(m_backbuffer_width) / static_cast<float>(m_backbuffer_height));
-
-  // The actual aspect ratio of the XFB texture is irrelevant, the VI one is the one that matters
-  const auto& vi = Core::System::GetInstance().GetVideoInterface();
-  const float source_aspect_ratio = vi.GetAspectRatio();
-
-  // This will scale up the source ~4:3 resolution to its equivalent ~16:9 resolution
-  if (aspect_mode == AspectMode::ForceWide ||
-      (aspect_mode == AspectMode::Auto && g_widescreen->IsGameWidescreen()))
-  {
-    return SourceAspectRatioToWidescreen(source_aspect_ratio);
-  }
-  else if (aspect_mode == AspectMode::Custom)
   {
-    return source_aspect_ratio * (g_ActiveConfig.GetCustomAspectRatio() / (4.0f / 3.0f));
+    resulting_aspect_ratio =
+        (static_cast<float>(m_backbuffer_width) / static_cast<float>(m_backbuffer_height));
   }
-  // For the "custom stretch" mode, we force the exact target aspect ratio, without
-  // acknowleding the difference between the source aspect ratio and 4:3.
-  else if (aspect_mode == AspectMode::CustomStretch)
+  else
   {
-    return g_ActiveConfig.GetCustomAspectRatio();
+    // The actual aspect ratio of the XFB texture is irrelevant, the VI one is the one that matters
+    const auto& vi = Core::System::GetInstance().GetVideoInterface();
+    const float source_aspect_ratio = vi.GetAspectRatio();
+
+    // This will scale up the source ~4:3 resolution to its equivalent ~16:9 resolution
+    if (aspect_mode == AspectMode::ForceWide ||
+        (aspect_mode == AspectMode::Auto && g_widescreen->IsGameWidescreen()))
+    {
+      resulting_aspect_ratio = SourceAspectRatioToWidescreen(source_aspect_ratio);
+    }
+    else if (aspect_mode == AspectMode::Custom)
+    {
+      resulting_aspect_ratio =
+          source_aspect_ratio * (g_ActiveConfig.GetCustomAspectRatio() / (4.0f / 3.0f));
+    }
+    // For the "custom stretch" mode, we force the exact target aspect ratio, without
+    // acknowledging the difference between the source aspect ratio and 4:3.
+    else if (aspect_mode == AspectMode::CustomStretch)
+    {
+      resulting_aspect_ratio = g_ActiveConfig.GetCustomAspectRatio();
+    }
+    else if (aspect_mode == AspectMode::Raw)
+    {
+      resulting_aspect_ratio =
+          m_xfb_entry ? (static_cast<float>(m_last_xfb_width) / m_last_xfb_height) : 1.f;
+    }
+    else
+    {
+      resulting_aspect_ratio = source_aspect_ratio;
+    }
   }
-  else if (aspect_mode == AspectMode::Raw)
+
+  if (g_ActiveConfig.stereo_per_eye_resolution_full)
   {
-    return m_xfb_entry ? (static_cast<float>(m_last_xfb_width) / m_last_xfb_height) : 1.f;
+    if (g_ActiveConfig.stereo_mode == StereoMode::SBS)
+    {
+      // Render twice as wide if using side-by-side 3D, since the 3D will halve the horizontal
+      // resolution
+      resulting_aspect_ratio *= 2.0;
+    }
+    else if (g_ActiveConfig.stereo_mode == StereoMode::TAB)
+    {
+      // Render twice as tall if using top-and-bottom 3D, since the 3D will halve the vertical
+      // resolution
+      resulting_aspect_ratio /= 2.0;
+    }
   }
 
-  return source_aspect_ratio;
+  return resulting_aspect_ratio;
 }
 
 void Presenter::AdjustRectanglesToFitBounds(MathUtil::Rectangle<int>* target_rect,
diff --git a/Source/Core/VideoCommon/VideoConfig.cpp b/Source/Core/VideoCommon/VideoConfig.cpp
index efa159795c..8ca1f4ec63 100644
--- a/Source/Core/VideoCommon/VideoConfig.cpp
+++ b/Source/Core/VideoCommon/VideoConfig.cpp
@@ -171,6 +171,7 @@ void VideoConfig::Refresh()
   color_correction.fHDRPaperWhiteNits = Config::Get(Config::GFX_CC_HDR_PAPER_WHITE_NITS);
 
   stereo_mode = Config::Get(Config::GFX_STEREO_MODE);
+  stereo_per_eye_resolution_full = Config::Get(Config::GFX_STEREO_PER_EYE_RESOLUTION_FULL);
   iStereoDepth = Config::Get(Config::GFX_STEREO_DEPTH);
   iStereoConvergencePercentage = Config::Get(Config::GFX_STEREO_CONVERGENCE_PERCENTAGE);
   bStereoSwapEyes = Config::Get(Config::GFX_STEREO_SWAP_EYES);
diff --git a/Source/Core/VideoCommon/VideoConfig.h b/Source/Core/VideoCommon/VideoConfig.h
index 1e5f03d0e5..5cce23bfd2 100644
--- a/Source/Core/VideoCommon/VideoConfig.h
+++ b/Source/Core/VideoCommon/VideoConfig.h
@@ -241,6 +241,7 @@ struct VideoConfig final
 
   // Stereoscopy
   StereoMode stereo_mode{};
+  bool stereo_per_eye_resolution_full = false;
   int iStereoDepth = 0;
   int iStereoConvergence = 0;
   int iStereoConvergencePercentage = 0;