Activate nVIDIA Optimus under Java/OpenGL?

Question

I know it's already asked several times with no clear answer and I already filed a bug to nVIDIA. However, I'm still seeking a better workaround than starting JavaFX in Prism-D3D engine (which immediately allows subsequent OpenGL context to be created via nVIDIA).

Environment:

• nVIDIA 860m, driver 337.88, 340.43, 340.66 (quadro driver)
• Java 8u11 (tested x86/x64 & Java 7 as well)

Tested and failed:

• nVIDIA Profile
• NvOptimusEnablement (custom launcher written in C)
• Calling OpenCL first (custom launcher written in C)
• Calling Cuda first (JCuda, it actually shows nVIDIA name but OpenGL remains unaffected)

Failed APIs:

• JavaFX8 ES2 pipeline (it does function, see https://github.com/AqD/JOGL-FX )
• JOGL 2.1.5

Workarounds:

• JavaFX8 D3D pipeline. All GLContext created after D3D initialization work.

I nailed the problem to a very simple sample, calling realtech-vr OpenGL Extension Viewer (written in .NET). Inside there is a native "infogl.dll" which reads GL information and apparently activates Optimus right after oevClientInitialize.

The weirdness is that, the simplest console program calling infogl.dll works:

    Win32.oevSetDriverVersion("10.18.10.3621", 2176);
    Win32.oevClientLoadDatabase(File.ReadAllText("C:\\Program Files (x86)\\realtech VR\\OpenGL Extensions Viewer 4.1\\extensions.xml"));
    Win32.oevClientInitialize();
    for (var i = 0; i <= 9; i++)
    {
        var tree = Marshal.PtrToStringAnsi(Win32.oevClientGetCapsAndExtTree(i));
        Console.WriteLine(tree.Split('\n').First(ln => ln.Contains("text_id=\"357\"")));
    }
    Console.ReadLine();

But the very same code in Java by JNA doesn't:

    infogl.INSTANCE.oevSetDriverVersion("10.18.10.3621", 2176);
    String extXml = null;
    try {
        extXml = new String(
                Files.readAllBytes(Paths.get("C:\\Program Files (x86)\\realtech VR\\OpenGL Extensions Viewer 4.1\\extensions.xml")),
                "UTF-8");
    } catch (IOException e) {
        throw new RuntimeException(e);
    }
    infogl.INSTANCE.oevClientLoadDatabase(extXml);
    infogl.INSTANCE.oevClientInitialize();
    for (int i = 0; i <= 9; i++)
    {
        String tree = infogl.INSTANCE.oevClientGetCapsAndExtTree(i);
        System.out.println(Arrays.asList(tree.split("\\n")).first(ln -> ln.contains("text_id=\"357\"")));
    }

And it's unrelated to executable name "java" - I have tried.

The JavaFX D3D solution is unsuitable because it reduces OpenGL FPS by half on AMD Radeon chips - I assume that must be just as bad on nVIDIA ones, and that's why I seek to get it work with ES2 pipeline.

Answer 1

Launching JVM from .NET apparently works (via jni4net). It crashes in nvoglv64.dll at the end of JavaFX finalization through.

using net.sf.jni4net;
using net.sf.jni4net.utils;
...

    public static void Main(string[] args)
    {
        InitializeOpenGL();
        var setup = new BridgeSetup();
        setup.AddClassPath(@"C:\Program Files\Java\jdk1.8.0_11\demo\javafx_samples\Modena.jar");
        setup.AddJVMOption("-Dprism.order=es2");
        setup.AddJVMOption("-Dprism.verbose=true");
        var env = Bridge.CreateJVM(setup);
        [email protected]("Greetings from C# to Java world!");
        Console.WriteLine("Initializing...");
        var klass = env.FindClass("modena/Modena");
        Console.WriteLine("Finding main()...");
        var mainMethodId = klass.getMethods().First(m => m.getName().Equals("main")).GetMethodId();
        Console.WriteLine("Calling main()...");
        env.CallStaticVoidMethod(klass, mainMethodId, Convertor.ParArrayStrongC2JString(env, new string[0]));
        Console.WriteLine("Ended, press enter");
        Console.ReadLine();
    }

    protected static void InitializeOpenGL()
    {
        Win32.oevSetDriverVersion("10.18.10.3621", 2176);
        Win32.oevClientLoadDatabase(File.ReadAllText("C:\\Program Files (x86)\\realtech VR\\OpenGL Extensions Viewer 4.1\\extensions.xml"));
        Win32.oevClientInitialize();
        for (var i = 0; i <= 9; i++)
        {
            var tree = Marshal.PtrToStringAnsi(Win32.oevClientGetCapsAndExtTree(i));
            Console.WriteLine(tree.Split('\n').First(ln => ln.Contains("text_id=\"357\"")));
        }
        // Optimus should be activated by now!
    }

I have yet found the real reason that Optimus is activated under .NET...... But it's very likely C/C++ of the same code wouldn't work, since it's exactly what Java version does (JNI calls)

PS: I just verified that "OpenTK" (.NET wrapper of OpenGL) cannot activate Optimus either. I'm totally confused.....