Tutorial 17: Helloworld mobile

This example show Hello World for Windows mobile. It compiles on other platform too. The only differences between the original examples are. You need a GUI, because otherwise you can't quit the application. You need a Filesystem, which is relative based to your executable.

#include <irrlicht.h>

#if defined ( _IRR_WINDOWS_ )
    #include <windows.h>
#endif

using namespace irr;
using namespace core;
using namespace scene;
using namespace video;
using namespace io;
using namespace gui;

#pragma comment(lib, "Irrlicht.lib")

class EventReceiver_basic : public IEventReceiver
{
private:
    IrrlichtDevice *Device;
public:
    EventReceiver_basic ( IrrlichtDevice *device ): Device ( device ) {}

    virtual bool OnEvent(const SEvent& event)
    {
        if (event.EventType == EET_GUI_EVENT)
        {
            s32 id = event.GUIEvent.Caller->getID();

            switch(event.GUIEvent.EventType)
            {
                case EGET_BUTTON_CLICKED:
                if (id == 2)
                {
                    Device->closeDevice();
                    return true;
                } break;
            }
        }

        return false;
    }
};

class CSampleSceneNode : public ISceneNode
{
    aabbox3d<f32> Box;
    S3DVertex Vertices[4];
    SMaterial Material;
public:

    CSampleSceneNode(ISceneNode* parent, ISceneManager* mgr, s32 id)
        : ISceneNode(parent, mgr, id)
    {
        Material.Wireframe = false;
        Material.Lighting = false;

        Vertices[0] = S3DVertex(0,0,10, 1,1,0, SColor(255,0,255,255), 0, 1);
        Vertices[1] = S3DVertex(10,0,-10, 1,0,0, SColor(255,255,0,255), 1, 1);
        Vertices[2] = S3DVertex(0,20,0, 0,1,1, SColor(255,255,255,0), 1, 0);
        Vertices[3] = S3DVertex(-10,0,-10, 0,0,1, SColor(255,0,255,0), 0, 0);
        Box.reset(Vertices[0].Pos);
        for (s32 i=1; i<4; ++i)
            Box.addInternalPoint(Vertices[i].Pos);
    }
    virtual void OnRegisterSceneNode()
    {
        if (IsVisible)
            SceneManager->registerNodeForRendering(this);

        ISceneNode::OnRegisterSceneNode();
    }

    virtual void render()
    {
        u16 indices[] = {   0,2,3, 2,1,3, 1,0,3, 2,0,1  };
        IVideoDriver* driver = SceneManager->getVideoDriver();

        driver->setMaterial(Material);
        driver->setTransform(ETS_WORLD, AbsoluteTransformation);
        driver->drawIndexedTriangleList(&Vertices[0], 4, &indices[0], 4);
    }

    virtual const aabbox3d<f32>& getBoundingBox() const
    {
        return Box;
    }

    virtual u32 getMaterialCount()
    {
        return 1;
    }

    virtual SMaterial& getMaterial(u32 i)
    {
        return Material;
    }   
};

! Startup a Windows Mobile Device

IrrlichtDevice *startup()
{
    // both software and burnings video can be used
    E_DRIVER_TYPE driverType = EDT_SOFTWARE; // EDT_BURNINGSVIDEO;

    // create device
    IrrlichtDevice *device = 0;

#if defined (_IRR_USE_WINDOWS_CE_DEVICE_)
    // set to standard mobile fullscreen 240x320
    device = createDevice(driverType, dimension2d<u32>(240, 320), 16, true );
#else
    // on PC. use window mode
    device = createDevice(driverType, dimension2d<u32>(240, 320), 16, false );
#endif      
    if ( 0 == device )
        return 0;

    IVideoDriver* driver = device->getVideoDriver();
    ISceneManager* smgr = device->getSceneManager();
    IGUIEnvironment* guienv = device->getGUIEnvironment();

    // set the filesystem relative to the executable
#if defined (_IRR_WINDOWS_)
    {
        wchar_t buf[255];
        GetModuleFileNameW ( 0, buf, 255 );

        io::path base = buf;
        base = base.subString ( 0, base.findLast ( '\\' ) + 1 );
        device->getFileSystem()->addFileArchive ( base );
    }
#endif

    IGUIStaticText *text = guienv->addStaticText(L"FPS: 25",
        rect<s32>(140,15,200,30), false, false, 0, 100 );

    guienv->addButton(core::rect<int>(200,10,238,30), 0, 2, L"Quit");

    // add irrlicht logo
    guienv->addImage(driver->getTexture("../../media/irrlichtlogo3.png"),
                    core::position2d<s32>(0,-2));
    return device;
}

!

int run ( IrrlichtDevice *device )
{
    while(device->run())
    if (device->isWindowActive())
    {
        device->getVideoDriver()->beginScene(true, true, SColor(0,100,100,100));
        device->getSceneManager()->drawAll();
        device->getGUIEnvironment()->drawAll();
        device->getVideoDriver()->endScene ();

        IGUIElement *stat = device->getGUIEnvironment()->
            getRootGUIElement()->getElementFromId ( 100 );
        if ( stat )
        {
            stringw str = L"FPS: ";
            str += (s32)device->getVideoDriver()->getFPS();

            stat->setText ( str.c_str() );
        }
    }

    device->drop();
    return 0;
}

!

int example_customscenenode()
{
    // create device
    IrrlichtDevice *device = startup();
    if (device == 0)
        return 1; // could not create selected driver.

    // create engine and camera
    EventReceiver_basic receiver(device);
    device->setEventReceiver(&receiver);
    
    IVideoDriver* driver = device->getVideoDriver();
    ISceneManager* smgr = device->getSceneManager();
    IGUIEnvironment* guienv = device->getGUIEnvironment();


    smgr->addCameraSceneNode(0, vector3df(0,-40,0), vector3df(0,0,0));

    CSampleSceneNode *myNode = 
        new CSampleSceneNode(smgr->getRootSceneNode(), smgr, 666);

    ISceneNodeAnimator* anim = 
        smgr->createRotationAnimator(vector3df(0.8f, 0, 0.8f));

    if(anim)
    {
        myNode->addAnimator(anim);
        anim->drop();
        anim = 0; // As I shouldn't refer to it again, ensure that I can't
    }

    myNode->drop();
    myNode = 0; // As I shouldn't refer to it again, ensure that I can't

    return run ( device );
}

class EventReceiver_terrain : public IEventReceiver
{
public:

    EventReceiver_terrain(IrrlichtDevice *device, scene::ISceneNode* terrain, scene::ISceneNode* skybox, scene::ISceneNode* skydome) :
        Device ( device ), Terrain(terrain), Skybox(skybox), Skydome(skydome), showBox(true)
    {
        Skybox->setVisible(true);
        Skydome->setVisible(false);
    }

    bool OnEvent(const SEvent& event)
    {
        if (event.EventType == EET_GUI_EVENT)
        {
            s32 id = event.GUIEvent.Caller->getID();

            switch(event.GUIEvent.EventType)
            {
                case EGET_BUTTON_CLICKED:
                if (id == 2)
                {
                    Device->closeDevice();
                    return true;
                } break;
            }
        }

        // check if user presses the key 'W' or 'D'
        if (event.EventType == irr::EET_KEY_INPUT_EVENT && !event.KeyInput.PressedDown)
        {
            switch (event.KeyInput.Key)
            {
            case irr::KEY_KEY_W: // switch wire frame mode
                Terrain->setMaterialFlag(video::EMF_WIREFRAME,
                        !Terrain->getMaterial(0).Wireframe);
                Terrain->setMaterialFlag(video::EMF_POINTCLOUD, false);
                return true;
            case irr::KEY_KEY_P: // switch wire frame mode
                Terrain->setMaterialFlag(video::EMF_POINTCLOUD,
                        !Terrain->getMaterial(0).PointCloud);
                Terrain->setMaterialFlag(video::EMF_WIREFRAME, false);
                return true;
            case irr::KEY_KEY_D: // toggle detail map
                Terrain->setMaterialType(
                    Terrain->getMaterial(0).MaterialType == video::EMT_SOLID ?
                    video::EMT_DETAIL_MAP : video::EMT_SOLID);
                return true;
            case irr::KEY_KEY_S: // toggle skies
                showBox=!showBox;
                Skybox->setVisible(showBox);
                Skydome->setVisible(!showBox);
                return true;
            default:
                break;
            }
        }

        return false;
    }

private:
    IrrlichtDevice *Device;
    scene::ISceneNode* Terrain;
    scene::ISceneNode* Skybox;
    scene::ISceneNode* Skydome;
    bool showBox;
};

The start of the main function starts like in most other example. We ask the user for the desired renderer and start it up. This time with the advanced parameter handling.

int example_terrain()
{
    // create device
    IrrlichtDevice *device = startup();
    if (device == 0)
        return 1; // could not create selected driver.

First, we add standard stuff to the scene: A nice irrlicht engine logo, a small help text, a user controlled camera, and we disable the mouse cursor.

video::IVideoDriver* driver = device->getVideoDriver();
scene::ISceneManager* smgr = device->getSceneManager();
gui::IGUIEnvironment* env = device->getGUIEnvironment();


//set other font
//env->getSkin()->setFont(env->getFont("../../media/fontlucida.png"));

// add some help text
env->addStaticText(
    L"Press 'W' to change wireframe mode\nPress 'D' to toggle detail map\nPress 'S' to toggle skybox/skydome",
    core::rect<s32>(5,250,235,320), true, true, 0, -1, true);

// add camera
scene::ICameraSceneNode* camera =
    smgr->addCameraSceneNodeFPS(0,100.0f,1.2f);

camera->setPosition(core::vector3df(2700*2,255*2,2600*2));
camera->setTarget(core::vector3df(2397*2,343*2,2700*2));
camera->setFarValue(42000.0f);

// disable mouse cursor
device->getCursorControl()->setVisible(false);

Here comes the terrain renderer scene node: We add it just like any other scene node to the scene using ISceneManager::addTerrainSceneNode(). The only parameter we use is a file name to the heightmap we use. A heightmap is simply a gray scale texture. The terrain renderer loads it and creates the 3D terrain from it.

To make the terrain look more big, we change the scale factor of it to (40, 4.4, 40). Because we don't have any dynamic lights in the scene, we switch off the lighting, and we set the file terrain-texture.jpg as texture for the terrain and detailmap3.jpg as second texture, called detail map. At last, we set the scale values for the texture: The first texture will be repeated only one time over the whole terrain, and the second one (detail map) 20 times.

// add terrain scene node
scene::ITerrainSceneNode* terrain = smgr->addTerrainSceneNode(
    "../../media/terrain-heightmap.bmp",
    0,                  // parent node
    -1,                 // node id
    core::vector3df(0.f, 0.f, 0.f),     // position
    core::vector3df(0.f, 0.f, 0.f),     // rotation
    core::vector3df(40.f, 4.4f, 40.f),  // scale
    video::SColor ( 255, 255, 255, 255 ),   // vertexColor
    5,                  // maxLOD
    scene::ETPS_17,             // patchSize
    4                   // smoothFactor
    );

if ( terrain )
{
    terrain->setMaterialFlag(video::EMF_LIGHTING, false);

    terrain->setMaterialTexture(0,
            driver->getTexture("../../media/terrain-texture.jpg"));
    terrain->setMaterialTexture(1,
            driver->getTexture("../../media/detailmap3.jpg"));
    
    terrain->setMaterialType(video::EMT_DETAIL_MAP);

    terrain->scaleTexture(1.0f, 20.0f);
    //terrain->setDebugDataVisible ( true );

To be able to do collision with the terrain, we create a triangle selector. If you want to know what triangle selectors do, just take a look into the collision tutorial. The terrain triangle selector works together with the terrain. To demonstrate this, we create a collision response animator and attach it to the camera, so that the camera will not be able to fly through the terrain.

// create triangle selector for the terrain 
scene::ITriangleSelector* selector
    = smgr->createTerrainTriangleSelector(terrain, 0);
terrain->setTriangleSelector(selector);

// create collision response animator and attach it to the camera
scene::ISceneNodeAnimator* anim = smgr->createCollisionResponseAnimator(
    selector, camera, core::vector3df(60,100,60),
    core::vector3df(0,0,0),
    core::vector3df(0,50,0));
selector->drop();
camera->addAnimator(anim);
anim->drop();

If you need access to the terrain data you can also do this directly via the following code fragment.

    scene::CDynamicMeshBuffer* buffer = new scene::CDynamicMeshBuffer(video::EVT_2TCOORDS, video::EIT_16BIT);
    terrain->getMeshBufferForLOD(*buffer, 0);
    video::S3DVertex2TCoords* data = (video::S3DVertex2TCoords*)buffer->getVertexBuffer().getData();
    // Work on data or get the IndexBuffer with a similar call.
    buffer->drop(); // When done drop the buffer again.
}

To make the user be able to switch between normal and wireframe mode, we create an instance of the event receiver from above and let Irrlicht know about it. In addition, we add the skybox which we already used in lots of Irrlicht examples and a skydome, which is shown mutually exclusive with the skybox by pressing 'S'.

    // create skybox and skydome
    driver->setTextureCreationFlag(video::ETCF_CREATE_MIP_MAPS, false);

    scene::ISceneNode* skybox=smgr->addSkyBoxSceneNode(
        driver->getTexture("../../media/irrlicht2_up.jpg"),
        driver->getTexture("../../media/irrlicht2_dn.jpg"),
        driver->getTexture("../../media/irrlicht2_lf.jpg"),
        driver->getTexture("../../media/irrlicht2_rt.jpg"),
        driver->getTexture("../../media/irrlicht2_ft.jpg"),
        driver->getTexture("../../media/irrlicht2_bk.jpg"));
    scene::ISceneNode* skydome=smgr->addSkyDomeSceneNode(driver->getTexture("../../media/skydome.jpg"),16,8,0.95f,2.0f);

    driver->setTextureCreationFlag(video::ETCF_CREATE_MIP_MAPS, true);

    // create event receiver
    EventReceiver_terrain receiver( device, terrain, skybox, skydome);
    device->setEventReceiver(&receiver);

    return run ( device );
}

int example_helloworld()
{
    // create device
    IrrlichtDevice *device = startup();
    if (device == 0)
        return 1; // could not create selected driver.

    IVideoDriver* driver = device->getVideoDriver();
    ISceneManager* smgr = device->getSceneManager();
    IGUIEnvironment* guienv = device->getGUIEnvironment();

    IAnimatedMesh* mesh = smgr->getMesh("../../media/sydney.md2");
    if (!mesh)
    {
        device->drop();
        return 1;
    }
    IAnimatedMeshSceneNode* node = smgr->addAnimatedMeshSceneNode( mesh );

To let the mesh look a little bit nicer, we change its material. We disable lighting because we do not have a dynamic light in here, and the mesh would be totally black otherwise. Then we set the frame loop, such that the predefined STAND animation is used. And last, we apply a texture to the mesh. Without it the mesh would be drawn using only a color.

if (node)
{
    node->setMaterialFlag(EMF_LIGHTING, false);
    node->setMD2Animation(scene::EMAT_STAND);
    node->setMaterialTexture( 0, driver->getTexture("../../media/sydney.bmp") );
}

To look at the mesh, we place a camera into 3d space at the position (0, 30, -40). The camera looks from there to (0,5,0), which is approximately the place where our md2 model is.

    smgr->addCameraSceneNode(0, vector3df(0,30,-40), vector3df(0,5,0));

    EventReceiver_basic receiver(device);
    device->setEventReceiver(&receiver);

    return run ( device );

}

#if defined (_IRR_USE_WINDOWS_CE_DEVICE_)
    #pragma comment(linker, "/subsystem:WINDOWSCE /ENTRY:main") 
#elif defined (_IRR_WINDOWS_)
    #pragma comment(linker, "/subsystem:windows /ENTRY:mainCRTStartup")
#endif

int main()
{
    example_helloworld ();
    example_customscenenode();
    //example_terrain();
}