From c22dc143d1c1e6ff831b112f8d1de0b1f28d7a22 Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Tue, 30 Jan 2018 12:19:53 +0100
Subject: [PATCH] [d3d119 Implemented DXVK_FEATURE_LEVEL to restrict D3D
 feature levels

---
 src/d3d11/d3d11_device.cpp | 26 +++++++++++++++++++++++++-
 src/d3d11/d3d11_device.h   |  2 ++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/src/d3d11/d3d11_device.cpp b/src/d3d11/d3d11_device.cpp
index 16c39462..b06b6feb 100644
--- a/src/d3d11/d3d11_device.cpp
+++ b/src/d3d11/d3d11_device.cpp
@@ -1361,7 +1361,7 @@ namespace dxvk {
     const Rc<DxvkAdapter>&  adapter,
           D3D_FEATURE_LEVEL featureLevel) {
     // We currently only support 11_0 interfaces
-    if (featureLevel > D3D_FEATURE_LEVEL_11_0)
+    if (featureLevel > GetMaxFeatureLevel())
       return false;
     
     // Check whether all features are supported
@@ -2170,4 +2170,28 @@ namespace dxvk {
     m_resourceInitCommands = 0;
   }
   
+  
+  D3D_FEATURE_LEVEL D3D11Device::GetMaxFeatureLevel() {
+    static const std::array<std::pair<std::string, D3D_FEATURE_LEVEL>, 6> s_featureLevels = {{
+      { "11_0", D3D_FEATURE_LEVEL_11_0 },
+      { "10_1", D3D_FEATURE_LEVEL_10_1 },
+      { "10_0", D3D_FEATURE_LEVEL_10_0 },
+      { "9_3",  D3D_FEATURE_LEVEL_9_3  },
+      { "9_2",  D3D_FEATURE_LEVEL_9_2  },
+      { "9_1",  D3D_FEATURE_LEVEL_9_1  },
+    }};
+    
+    const std::string maxLevel = env::getEnvVar(L"DXVK_FEATURE_LEVEL");
+    
+    auto entry = std::find_if(s_featureLevels.begin(), s_featureLevels.end(),
+      [&] (const std::pair<std::string, D3D_FEATURE_LEVEL>& pair) {
+        return pair.first == maxLevel;
+      });
+    
+    return entry != s_featureLevels.end()
+      ? entry->second
+      : D3D_FEATURE_LEVEL_11_0;
+    
+  }
+  
 }
diff --git a/src/d3d11/d3d11_device.h b/src/d3d11/d3d11_device.h
index ee4f0333..88ba89d7 100644
--- a/src/d3d11/d3d11_device.h
+++ b/src/d3d11/d3d11_device.h
@@ -333,6 +333,8 @@ namespace dxvk {
     void UnlockResourceInitContext(uint64_t CommandCount);
     void SubmitResourceInitCommands();
     
+    static D3D_FEATURE_LEVEL GetMaxFeatureLevel();
+    
   };
   
 }