From dfa7cc869c7c00a124ff3f2170c5de6809ee1ea9 Mon Sep 17 00:00:00 2001
From: cdozdil <cdozdil@gmail.com>
Date: Mon, 1 Jun 2026 22:24:29 +0300
Subject: [PATCH] Improved auto FSR3.X/4 selection

---
 OptiScaler/State.h              | 13 +++++++++++++
 OptiScaler/Util.cpp             | 27 +++++++++++++++++++++++++++
 OptiScaler/fsr4/FSR4Upgrade.cpp | 19 +++++++++++++++++--
 3 files changed, 57 insertions(+), 2 deletions(-)

diff --git a/OptiScaler/State.h b/OptiScaler/State.h
index db13c644..c748bcfe 100644
--- a/OptiScaler/State.h
+++ b/OptiScaler/State.h
@@ -10,6 +10,18 @@
 #include <ankerl/unordered_dense.h>
 #include <mutex>
 
+typedef enum WindowsVersion
+{
+    Unknown = 0,
+    WindowsXP,
+    WindowsVista,
+    Windows7,
+    Windows8,
+    Windows8_1,
+    Windows10,
+    Windows11,
+} WindowsVersion;
+
 typedef enum API
 {
     NotSelected = 0,
@@ -89,6 +101,7 @@ class State
     std::string GameVersion;
     GameEngineType GameEngine = GameEngineType::Other;
     ankerl::unordered_dense::map<void*, std::string> DeviceAdapterNames;
+    WindowsVersion WindowsVer = WindowsVersion::Unknown;
 
     bool NvngxDx11Inited = false;
     bool NvngxDx12Inited = false;
diff --git a/OptiScaler/Util.cpp b/OptiScaler/Util.cpp
index f9594450..c6938ed3 100644
--- a/OptiScaler/Util.cpp
+++ b/OptiScaler/Util.cpp
@@ -97,19 +97,46 @@ std::string Util::GetWindowsName(const OSVERSIONINFOW& os)
     DWORD build = os.dwBuildNumber;
 
     if (major == 10 && build >= 22000)
+    {
+        State::Instance().WindowsVer = WindowsVersion::Windows11;
         return "Windows 11";
+    }
+
     if (major == 10)
+    {
+        State::Instance().WindowsVer = WindowsVersion::Windows10;
         return "Windows 10";
+    }
+
     if (major == 6 && minor == 3)
+    {
+        State::Instance().WindowsVer = WindowsVersion::Windows8_1;
         return "Windows 8.1";
+    }
+
     if (major == 6 && minor == 2)
+    {
+        State::Instance().WindowsVer = WindowsVersion::Windows8;
         return "Windows 8";
+    }
+
     if (major == 6 && minor == 1)
+    {
+        State::Instance().WindowsVer = WindowsVersion::Windows7;
         return "Windows 7";
+    }
+
     if (major == 6 && minor == 0)
+    {
+        State::Instance().WindowsVer = WindowsVersion::WindowsVista;
         return "Windows Vista";
+    }
+
     if (major == 5 && minor == 1)
+    {
+        State::Instance().WindowsVer = WindowsVersion::WindowsXP;
         return "Windows XP";
+    }
 
     return "Unknown Windows Version";
 }
diff --git a/OptiScaler/fsr4/FSR4Upgrade.cpp b/OptiScaler/fsr4/FSR4Upgrade.cpp
index 5ec54ec5..13bbf034 100644
--- a/OptiScaler/fsr4/FSR4Upgrade.cpp
+++ b/OptiScaler/fsr4/FSR4Upgrade.cpp
@@ -186,8 +186,23 @@ void CheckForGPU()
 
                     if (!Config::Instance()->Dx12Upscaler.has_value())
                     {
-                        LOG_INFO("Setting Dx12Upscaler to fsr31 because RDNA4 GPU is detected");
-                        Config::Instance()->Dx12Upscaler.set_volatile_value("fsr31");
+                        if (State::Instance().WindowsVer == WindowsVersion::Windows11)
+                        {
+                            LOG_INFO("Setting Dx12Upscaler to fsr31 because RDNA4 GPU is detected");
+                            Config::Instance()->Dx12Upscaler.set_volatile_value("fsr31");
+                        }
+                        else
+                        {
+                            if (KernelBaseProxy::GetModuleHandleW_()(L"D3D12Core.dll") != nullptr)
+                            {
+                                LOG_INFO("Setting Dx12Upscaler to fsr31 because RDNA4 GPU is detected");
+                                Config::Instance()->Dx12Upscaler.set_volatile_value("fsr31");
+                            }
+                            else
+                            {
+                                LOG_WARN("RDNA4 GPU is detected but Agility SDK is not detected!");
+                            }
+                        }
                     }
                 }
             }