fix: detect Wine host, use D3D11 on macOS

MacOS doesn't support a cool enough desktop OpenGL version for us to
launch when using the Desktop OpenGL backend of ANGLE.

We now detect the presence of Wine and query it for the host platform
(analogous to `uname`).

On Wine macOS we select D3D11. This platform requires use of libraries
like D3DMetal/GPTK in Kegworks to emulate D3D11 enough.

On Wine Linux we select Desktop OpenGL as D3D11 requires use of DXVK
to function well enough.

On proper Windows we select D3D11 and for any other platforms we don't
indicate any preference for now.

Author: zao

engine/system/win/sys_video.cpp

@@ -99,17 +99,24 @@ void sys_IVideo::FreeHandle(sys_IVideo* hnd)
 }
 
 
-using WineGetVersionFun = const char* ();
-static bool RunningOnWine()
+static std::string GetWineHostVersion()
 {
 #ifdef _WIN32
+	using WineHostVersionFun = void (const char** /*sysname*/, const char** /*release*/);
 	HMODULE mod = GetModuleHandleA("ntdll.dll");
 	if (!mod)
-		return false;
-	auto ptr = GetProcAddress(mod, "wine_get_version");
-	return !!ptr;
+		return "";
+	auto ptr = GetProcAddress(mod, "wine_get_host_version");
+	if (!ptr)
+		return "";
+	auto fun = (WineHostVersionFun*)ptr;
+	const char* sysname{};
+	const char* release{};
+	fun(&sysname, &release);
+	return sysname ? sysname : "";
+#else
+	return "";
 #endif
-	return false;
 }
 
 sys_video_c::sys_video_c(sys_IMain* sysHnd)
@@ -121,9 +128,16 @@ sys_video_c::sys_video_c(sys_IMain* sysHnd)
 
 	strcpy(curTitle, CFG_TITLE);
 
-	const int platformType = RunningOnWine()
-		? GLFW_ANGLE_PLATFORM_TYPE_OPENGL
-		: GLFW_ANGLE_PLATFORM_TYPE_D3D11;
+	int platformType = GLFW_ANGLE_PLATFORM_TYPE_NONE;
+#ifdef _WIN32
+	const std::string wineHost = GetWineHostVersion();
+	if (wineHost == "Linux")
+		platformType = GLFW_ANGLE_PLATFORM_TYPE_OPENGL;
+	else if (wineHost == "Darwin")
+		platformType = GLFW_ANGLE_PLATFORM_TYPE_D3D11;
+	else // Native Windows
+		platformType = GLFW_ANGLE_PLATFORM_TYPE_D3D11;
+#endif
 	glfwInitHint(GLFW_ANGLE_PLATFORM_TYPE, platformType);
 	glfwInit();
 }