Repair Nvidia black-screen fix to reenable ENB mod loading.

The ENB mod places a proxy DLL in the SkyrimSE.exe directory to hook the D3D11 functions it needs. But SkyrimTogether.exe launches from a different directory, so the default DLL search path doesn't find it. Check for existence of the DLL and load it if found.

Also fixes a minor invocation bug.

Code/client/NvidiaUtil.cpp

@@ -1,4 +1,5 @@
 #include "NvidiaUtil.h"
+#include "immersive_launcher/launcher.h"
 #include <d3d11.h>
 
 bool IsNvidiaOverlayLoaded()
@@ -9,8 +10,20 @@ bool IsNvidiaOverlayLoaded()
 // This makes the Nvidia overlay happy.
 // The call to D3D11CreateDevice probably causes some of their
 // internal hooks to be called and do the required init work before the game window opens.
-HRESULT CreateEarlyDxDevice(ID3D11Device* apOutDevice, D3D_FEATURE_LEVEL* apOutFeatureLevel)
+HRESULT CreateEarlyDxDevice(ID3D11Device** appOutDevice, D3D_FEATURE_LEVEL* apOutFeatureLevel)
 {
-    return D3D11CreateDevice(nullptr, D3D_DRIVER_TYPE_HARDWARE, nullptr, 0, nullptr, 0, D3D11_SDK_VERSION, &apOutDevice,
-                             apOutFeatureLevel, nullptr);
+    // ENB (https://enbdev.org) works by injecting a proxy d3d11.dll into the SkyrimSE.exe
+    // directory. It won't be loaded if SkyrimTogether.exe compile-time links to d3d11.dll, 
+    // as it is in a different directory. To fix, launch ENB version if it is there, otherwise
+    // launch via the standard search path.
+    auto LC = launcher::GetLaunchContext();
+    auto d3d11Path = LC->gamePath / "d3d11.dll";
+    auto pModule = LoadLibraryExW(d3d11Path.c_str(), nullptr, LOAD_WITH_ALTERED_SEARCH_PATH);
+
+    // If that failed, standard lookup.
+    if (!pModule)
+        pModule = LoadLibraryExW(d3d11Path.filename().c_str(), nullptr, 0);
+    const auto pD3D11CreateDevice = reinterpret_cast<decltype(&D3D11CreateDevice)>(GetProcAddress(pModule, "D3D11CreateDevice"));
+
+    return pD3D11CreateDevice(nullptr, D3D_DRIVER_TYPE_HARDWARE, nullptr, 0, nullptr, 0, D3D11_SDK_VERSION, appOutDevice, apOutFeatureLevel, nullptr);
 }

Code/client/NvidiaUtil.h

@@ -5,4 +5,4 @@
 
 bool IsNvidiaOverlayLoaded();
 
-HRESULT CreateEarlyDxDevice(ID3D11Device* apOutDevice, D3D_FEATURE_LEVEL* apOutFeatureLevel);
+HRESULT CreateEarlyDxDevice(ID3D11Device** appOutDevice, D3D_FEATURE_LEVEL* apOutFeatureLevel);

Code/client/TiltedOnlineApp.cpp

@@ -119,11 +119,11 @@ void TiltedOnlineApp::UninstallHooks()
 
 void TiltedOnlineApp::ApplyNvidiaFix() noexcept
 {
-    auto d3dFeatureLevel = D3D_FEATURE_LEVEL_11_0;
-    HRESULT hr = CreateEarlyDxDevice(m_pDevice, &d3dFeatureLevel);
+    D3D_FEATURE_LEVEL d3dFeatureLevelOut;
+    HRESULT hr = CreateEarlyDxDevice(&m_pDevice, &d3dFeatureLevelOut);
     if (FAILED(hr))
         spdlog::error("D3D11CreateDevice failed. Detected an NVIDIA GPU, error code={0:x}", hr);
 
-    if (d3dFeatureLevel < D3D_FEATURE_LEVEL_11_0)
+    if (d3dFeatureLevelOut < D3D_FEATURE_LEVEL_11_0)
         spdlog::warn("Unexpected D3D11 feature level detected (< 11.0), may cause issues");
 }