This is the source for BloodyMess Tutorial 4.

#include "ExampleApplication.h"

#include <NxOgre.h>
#include <NxOgreOGRE3D.h>

class BloodyMessTutorial4Listener : public ExampleFrameListener
{ 
public:
    BloodyMessTutorial4Listener(RenderWindow *win, Camera *cam) 
        : ExampleFrameListener(win, cam)
    {
        mTimeController = NxOgre::TimeController::getSingleton();
    }

    bool frameStarted(const FrameEvent& evt)
    {
        mTimeController->advance(evt.timeSinceLastFrame);
        return ExampleFrameListener::frameStarted(evt);
    }

protected:
    NxOgre::TimeController*        mTimeController;
};

class BloodyMessTutorial4 : public ExampleApplication, public NxOgre::Callback
{
protected:
    NxOgre::World*            mWorld;
    NxOgre::Scene*            mScene;
    NxOgre::TimeController*        mTimeController;
    OGRE3DRenderSystem*        mRenderSystem;

    OGRE3DBody*            mCube;
    NxOgre::Volume*            mVolume;

    void createScene()
    {
        // Set ambient light
        mSceneMgr->setAmbientLight(ColourValue(0.5f, 0.5f, 0.5f));

        // Create a light
        Light* l = mSceneMgr->createLight("MainLight");
        l->setPosition(20, 80, 50);

        // Position the camera
        mCamera->setPosition(0, 20, 80);
        mCamera->lookAt(0, 20, 0);

        // Create the world
        mWorld = NxOgre::World::createWorld();

        // Create scene description
        NxOgre::SceneDescription sceneDesc;
        sceneDesc.mGravity = NxOgre::Vec3(0, -9.81f, 0);
        sceneDesc.mName = "DemoScene";

        // Create scene
        mScene = mWorld->createScene(sceneDesc);

        // Set some physical scene values
        mScene->getMaterial(0)->setStaticFriction(0.5);
        mScene->getMaterial(0)->setDynamicFriction(0.5);
        mScene->getMaterial(0)->setRestitution(0.1);

        // Create render system
        mRenderSystem = new OGRE3DRenderSystem(mScene);

        //Create time controller
        mTimeController = NxOgre::TimeController::getSingleton();

        // Add objects
        mCube = mRenderSystem->createBody(new NxOgre::Box(1, 1, 1), NxOgre::Vec3(0, 10, 0), "cube.1m.mesh");
        
        // Create floor plane (Ogre)
        MovablePlane *plane = new MovablePlane("Plane");
        plane->d = 0;
        plane->normal = Vector3::UNIT_Y;
        Ogre::MeshManager::getSingleton().createPlane("PlaneMesh", 
            ResourceGroupManager::DEFAULT_RESOURCE_GROUP_NAME, 
            *plane, 120, 120, 1, 1, true, 1, 3, 3, Vector3::UNIT_Z);
        Entity *planeEnt = mSceneMgr->createEntity("PlaneEntity", "PlaneMesh");
        planeEnt->setMaterialName("Examples/GrassFloor");

        Ogre::SceneNode* mPlaneNode = mSceneMgr->getRootSceneNode()->createChildSceneNode();
        mPlaneNode->attachObject(planeEnt);

        mVolume = mScene->createVolume(new NxOgre::Box(5), NxOgre::Matrix44(NxOgre::Vec3(0, 0, 0)), this, NxOgre::Enums::VolumeCollisionType_All);
    }

    // Create a new frame listener
    void createFrameListener()
    {
        mFrameListener = new BloodyMessTutorial4Listener(mWindow, mCamera);
        mRoot->addFrameListener(mFrameListener);
    }

    void onVolumeEvent(NxOgre::Volume* volume, NxOgre::Shape* volumeShape, NxOgre::RigidBody* rigidBody, NxOgre::Shape* rigidBodyShape, unsigned int collisionEvent)
    {
        if(collisionEvent == NxOgre::Enums::VolumeCollisionType_OnEnter)
        {
            NxOgre::Actor* actor = static_cast<NxOgre::Actor*>(rigidBody);
            float y =   (9.81 * actor->getMass())                  // counteract gravity
                + (-actor->getLinearVelocity().y * actor->getMass())      // counteract vertical velocity
                + (10 - actor->getGlobalPosition().y * actor->getMass()); // Add some force to move it to the top

            actor->addForce(NxOgre::Vec3(0, y, 0), NxOgre::Enums::ForceMode_Impulse); 
        }
    }
};

#if OGRE_PLATFORM == OGRE_PLATFORM_WIN32
#define WIN32_LEAN_AND_MEAN
#include "windows.h"
#endif

#ifdef __cplusplus
extern "C" {
#endif

#if OGRE_PLATFORM == OGRE_PLATFORM_WIN32
    INT WINAPI WinMain(HINSTANCE hInst, HINSTANCE, LPSTR strCmdLine, INT)
#else
    int main(int argc, char **argv)
#endif
    {
        // Create application object
        BloodyMessTutorial4 app;

        try {
            app.go();
        } catch(Exception& e) {
#if OGRE_PLATFORM == OGRE_PLATFORM_WIN32
            MessageBoxA(NULL, e.getFullDescription().c_str(),
                "An exception has occurred!", MB_OK | MB_ICONERROR | MB_TASKMODAL);
#else
            std::cerr << "An exception has occurred: " << e.getFullDescription();
#endif
        }

        return 0;
    }

#ifdef __cplusplus
}
#endif