Request execution on dedicated GPU on Windows

src/porting.cpp

@@ -70,6 +70,15 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include <cstdarg>
 #include <cstdio>
 
+#if !defined(SERVER) && defined(_WIN32)
+// On Windows export some driver-specific variables to encourage Minetest to be
+// executed on the discrete GPU in case of systems with two. Portability is fun.
+extern "C" {
+	__declspec(dllexport) DWORD NvOptimusEnablement = 1;
+	__declspec(dllexport) DWORD AmdPowerXpressRequestHighPerformance = 1;
+}
+#endif
+
 namespace porting
 {