Irrlicht 3D Engine
Tutorial 22: Material Viewer
022shot.jpg

This example can be used to play around with material settings and watch the results. Only the default non-shader materials are used in here.

You have two nodes to make it easier to see which difference your settings will make. Additionally you have one lightscenenode and you can set the global ambient values.

#include <irrlicht.h>
#include "driverChoice.h"

using namespace irr;

#ifdef _MSC_VER
#pragma comment(lib, "Irrlicht.lib")
#endif

Variables within the empty namespace are globals which are restricted to this file.

namespace
{
    const wchar_t* const DriverTypeNames[] =
    {
        L"NULL",
        L"SOFTWARE",
        L"BURNINGSVIDEO",
        L"DIRECT3D8",
        L"DIRECT3D9",
        L"OPENGL",
        0,
    };

    // For the gui id's
    enum EGUI_IDS
    {
        GUI_ID_OPEN_TEXTURE = 1,
        GUI_ID_QUIT,
        GUI_ID_MAX
    };

    // Name used in texture selection to clear the textures on the node
    const core::stringw CLEAR_TEXTURE = L"CLEAR texture";

    // some useful color constants
    const video::SColor SCOL_BLACK     = video::SColor(255, 0,   0,   0);
    const video::SColor SCOL_BLUE      = video::SColor(255, 0,   0,  255);
    const video::SColor SCOL_CYAN      = video::SColor(255, 0,  255, 255);
    const video::SColor SCOL_GRAY      = video::SColor(255, 128,128, 128);
    const video::SColor SCOL_GREEN     = video::SColor(255, 0,  255,  0);
    const video::SColor SCOL_MAGENTA   = video::SColor(255, 255, 0,  255);
    const video::SColor SCOL_RED       = video::SColor(255, 255, 0,   0);
    const video::SColor SCOL_YELLOW    = video::SColor(255, 255, 255, 0);
    const video::SColor SCOL_WHITE     = video::SColor(255, 255, 255, 255);
};  // namespace

Returns a new unique number on each call.

s32 makeUniqueId()
{
    static int unique = GUI_ID_MAX;
    ++unique;
    return unique;
}

Find out which vertex-type is needed for the given material type.

Custom GUI-control to edit colorvalues.

class CColorControl : public gui::IGUIElement
{
public:
    // Constructor
    CColorControl(gui::IGUIEnvironment* guiEnv, const core::position2d<s32> & pos, const wchar_t *text, IGUIElement* parent, s32 id=-1 )
        : gui::IGUIElement(gui::EGUIET_ELEMENT, guiEnv, parent,id, core::rect< s32 >(pos, pos+core::dimension2d<s32>(80, 75)))
        , DirtyFlag(true)
        , ColorStatic(0)
        , EditAlpha(0)
        , EditRed(0)
        , EditGreen(0)
        , EditBlue(0)
    {
        using namespace gui;
        ButtonSetId = makeUniqueId();

        const core::rect< s32 > rectControls(0,0,AbsoluteRect.getWidth(),AbsoluteRect.getHeight() );
        IGUIStaticText * groupElement = guiEnv->addStaticText (L"", rectControls, true, false, this, -1, false);
        groupElement->setNotClipped(true);

        guiEnv->addStaticText (text, core::rect<s32>(0,0,80,15), false, false, groupElement, -1, false);

        EditAlpha = addEditForNumbers(guiEnv, core::position2d<s32>(0,15), L"a", -1, groupElement );
        EditRed = addEditForNumbers(guiEnv, core::position2d<s32>(0,30), L"r", -1, groupElement );
        EditGreen = addEditForNumbers(guiEnv, core::position2d<s32>(0,45), L"g", -1, groupElement );
        EditBlue = addEditForNumbers(guiEnv, core::position2d<s32>(0,60), L"b", -1, groupElement );

        ColorStatic = guiEnv->addStaticText (L"", core::rect<s32>(60,15,80,75), true, false, groupElement, -1, true);

        guiEnv->addButton (core::rect<s32>(60,35,80,50), groupElement, ButtonSetId, L"set");
        SetEditsFromColor(Color);
    }

    // event receiver
    virtual bool OnEvent(const SEvent &event)
    {
        if ( event.EventType != EET_GUI_EVENT )
            return false;

        if ( event.GUIEvent.Caller->getID() == ButtonSetId && event.GUIEvent.EventType == gui::EGET_BUTTON_CLICKED )
        {
            Color = GetColorFromEdits();
            SetEditsFromColor(Color);
        }

        return false;
    }

    // set the color values
    void setColor(const video::SColor& col)
    {
        DirtyFlag = true;
        Color = col;
        SetEditsFromColor(Color);
    }

    // get the color values
    const video::SColor& getColor() const
    {
        return Color;
    }

    // To reset the dirty flag
    void resetDirty()
    {
        DirtyFlag = false;
    }

    // when the color was changed the dirty flag is set
    bool isDirty() const
    {
        return DirtyFlag;
    };

protected:

    // Add a staticbox for a description + an editbox so users can enter numbers
    gui::IGUIEditBox* addEditForNumbers(gui::IGUIEnvironment* guiEnv, const core::position2d<s32> & pos, const wchar_t *text, s32 id, gui::IGUIElement * parent)
    {
        using namespace gui;

        core::rect< s32 > rect(pos, pos+core::dimension2d<s32>(10, 15));
        guiEnv->addStaticText (text, rect, false, false, parent, -1, false);
        rect += core::position2d<s32>( 20, 0 );
        rect.LowerRightCorner.X += 20;
        gui::IGUIEditBox* edit = guiEnv->addEditBox(L"0", rect, true, parent, id);
        return edit;
    }

    // Get the color value from the editfields
    video::SColor GetColorFromEdits()
    {
        video::SColor col;

        if (EditAlpha)
        {
            u32 alpha = core::strtoul10(core::stringc(EditAlpha->getText()).c_str());
            if (alpha > 255)
                alpha = 255;
            col.setAlpha(alpha);
        }

        if (EditRed)
        {
            u32 red = core::strtoul10(core::stringc(EditRed->getText()).c_str());
            if (red > 255)
                red = 255;
            col.setRed(red);
        }

        if (EditGreen)
        {
            u32 green = core::strtoul10(core::stringc(EditGreen->getText()).c_str());
            if (green > 255)
                green = 255;
            col.setGreen(green);
        }

        if (EditBlue)
        {
            u32 blue = core::strtoul10(core::stringc(EditBlue->getText()).c_str());
            if (blue > 255)
                blue = 255;
            col.setBlue(blue);
        }

        return col;
    }

    // Fill the editfields with the value for the given color
    void SetEditsFromColor(video::SColor col)
    {
        DirtyFlag = true;
        if ( EditAlpha )
            EditAlpha->setText( core::stringw(col.getAlpha()).c_str() );
        if ( EditRed )
            EditRed->setText( core::stringw(col.getRed()).c_str() );
        if ( EditGreen )
            EditGreen->setText( core::stringw(col.getGreen()).c_str() );
        if ( EditBlue )
            EditBlue->setText( core::stringw(col.getBlue()).c_str() );
        if ( ColorStatic )
            ColorStatic->setBackgroundColor(col);
    }

private:

    bool DirtyFlag;
    video::SColor Color;
    s32 ButtonSetId;
    gui::IGUIStaticText * ColorStatic;
    gui::IGUIEditBox * EditAlpha;
    gui::IGUIEditBox * EditRed;
    gui::IGUIEditBox * EditGreen;
    gui::IGUIEditBox * EditBlue;
};

Custom GUI-control for to edit all colors typically used in materials and lights

class CAllColorsControl : public gui::IGUIElement
{
public:
    // Constructor
    CAllColorsControl(gui::IGUIEnvironment* guiEnv, const core::position2d<s32> & pos, const wchar_t * description, bool hasEmissive, IGUIElement* parent, s32 id=-1)
        : gui::IGUIElement(gui::EGUIET_ELEMENT, guiEnv, parent,id, core::rect<s32>(pos,pos+core::dimension2d<s32>(60,250)))
        , ControlAmbientColor(0), ControlDiffuseColor(0), ControlSpecularColor(0), ControlEmissiveColor(0)
    {
        core::rect<s32> rect(0, 0, 60, 15);
        guiEnv->addStaticText (description, rect, false, false, this, -1, false);
        createColorControls(guiEnv, core::position2d<s32>(0, 15), hasEmissive);
    }

    // Destructor
    virtual ~CAllColorsControl()
    {
        ControlAmbientColor->drop();
        ControlDiffuseColor->drop();
        if ( ControlEmissiveColor )
            ControlEmissiveColor->drop();
        ControlSpecularColor->drop();
    }

    // Set the color values to those within the material
    void setColorsToMaterialColors(const video::SMaterial & material)
    {
        ControlAmbientColor->setColor(material.AmbientColor);
        ControlDiffuseColor->setColor(material.DiffuseColor);
        ControlEmissiveColor->setColor(material.EmissiveColor);
        ControlSpecularColor->setColor(material.SpecularColor);
    }

    // Update all changed colors in the material
    void updateMaterialColors(video::SMaterial & material)
    {
        if ( ControlAmbientColor->isDirty() )
            material.AmbientColor = ControlAmbientColor->getColor();
        if ( ControlDiffuseColor->isDirty() )
            material.DiffuseColor = ControlDiffuseColor->getColor();
        if ( ControlEmissiveColor->isDirty() )
            material.EmissiveColor = ControlEmissiveColor->getColor();
        if ( ControlSpecularColor->isDirty() )
            material.SpecularColor = ControlSpecularColor->getColor();
    }

    // Set the color values to those from the light data
    void setColorsToLightDataColors(const video::SLight & lightData)
    {
        ControlAmbientColor->setColor(lightData.AmbientColor.toSColor());
        ControlAmbientColor->setColor(lightData.DiffuseColor.toSColor());
        ControlAmbientColor->setColor(lightData.SpecularColor.toSColor());
    }

    // Update all changed colors in the light data
    void updateLightColors(video::SLight & lightData)
    {
        if ( ControlAmbientColor->isDirty() )
            lightData.AmbientColor = video::SColorf( ControlAmbientColor->getColor() );
        if ( ControlDiffuseColor->isDirty() )
            lightData.DiffuseColor = video::SColorf( ControlDiffuseColor->getColor() );
        if ( ControlSpecularColor->isDirty() )
            lightData.SpecularColor = video::SColorf(ControlSpecularColor->getColor() );
    }

    // To reset the dirty flags
    void resetDirty()
    {
        ControlAmbientColor->resetDirty();
        ControlDiffuseColor->resetDirty();
        ControlSpecularColor->resetDirty();
        if ( ControlEmissiveColor )
            ControlEmissiveColor->resetDirty();
    }

protected:
    void createColorControls(gui::IGUIEnvironment* guiEnv, const core::position2d<s32> & pos, bool hasEmissive)
    {
        ControlAmbientColor = new CColorControl( guiEnv, pos, L"ambient", this);
        ControlDiffuseColor = new CColorControl( guiEnv, pos + core::position2d<s32>(0, 75), L"diffuse", this );
        ControlSpecularColor = new CColorControl( guiEnv, pos + core::position2d<s32>(0, 150), L"specular", this );
        if ( hasEmissive )
        {
            ControlEmissiveColor = new CColorControl( guiEnv, pos + core::position2d<s32>(0, 225), L"emissive", this );
        }
    }

private:
    CColorControl*  ControlAmbientColor;
    CColorControl*  ControlDiffuseColor;
    CColorControl*  ControlSpecularColor;
    CColorControl*  ControlEmissiveColor;
};

GUI-Control to offer a selection of available textures.

class CTextureControl : public gui::IGUIElement
{
public:
    CTextureControl(gui::IGUIEnvironment* guiEnv, video::IVideoDriver * driver, const core::position2d<s32> & pos, IGUIElement* parent, s32 id=-1)
    : gui::IGUIElement(gui::EGUIET_ELEMENT, guiEnv, parent,id, core::rect<s32>(pos,pos+core::dimension2d<s32>(100,15)))
    , DirtyFlag(true), ComboTexture(0)
    {
        core::rect<s32> rectCombo(0, 0, AbsoluteRect.getWidth(),AbsoluteRect.getHeight());
        ComboTexture = guiEnv->addComboBox (rectCombo, this);
        updateTextures(driver);
    }

    virtual bool OnEvent(const SEvent &event)
    {
        if ( event.EventType != EET_GUI_EVENT )
            return false;

        if ( event.GUIEvent.Caller == ComboTexture && event.GUIEvent.EventType == gui::EGET_COMBO_BOX_CHANGED )
        {
            DirtyFlag = true;
        }

        return false;
    }

    // Workaround for a problem with comboboxes.
    // We have to get in front when the combobox wants to get in front or combobox-list might be drawn below other elements.
    virtual bool bringToFront(IGUIElement* element)
    {
        bool result = gui::IGUIElement::bringToFront(element);
        if ( Parent && element == ComboTexture )
            result &= Parent->bringToFront(this);
        return result;
    }

    // return selected texturename (if any, otherwise 0)
    const wchar_t * getSelectedTextureName() const
    {
        s32 selected = ComboTexture->getSelected();
        if ( selected < 0 )
            return 0;
        return ComboTexture->getItem(selected);
    }

    // reset the dirty flag
    void resetDirty()
    {
        DirtyFlag = false;
    }

    // when the texture was changed the dirty flag is set
    bool isDirty() const
    {
        return DirtyFlag;
    };

    // Put the names of all currently loaded textures in a combobox
    void updateTextures(video::IVideoDriver * driver)
    {
        s32 oldSelected = ComboTexture->getSelected();
        s32 selectNew = -1;
        const wchar_t * oldTextureName = 0;
        if ( oldSelected >= 0 )
        {
            oldTextureName = ComboTexture->getItem(oldSelected);
        }
        ComboTexture->clear();
        for ( u32 i=0; i < driver->getTextureCount(); ++i )
        {
            video::ITexture * texture = driver->getTextureByIndex(i);
            core::stringw name( texture->getName() );
            ComboTexture->addItem( name.c_str() );
            if ( oldTextureName && selectNew < 0 && name == oldTextureName )
                selectNew = i;
        }

        // add another name which can be used to clear the texture
        ComboTexture->addItem( CLEAR_TEXTURE.c_str() );
        if ( CLEAR_TEXTURE == oldTextureName )
            selectNew = ComboTexture->getItemCount()-1;

        if ( selectNew >= 0 )
            ComboTexture->setSelected(selectNew);

        DirtyFlag = true;
    }

private:
    bool DirtyFlag;
    gui::IGUIComboBox * ComboTexture;
};

Control which allows setting some of the material values for a meshscenenode

struct SMeshNodeControl
{
    // constructor
    SMeshNodeControl()
        : Initialized(false), Driver(0), MeshManipulator(0), SceneNode(0), SceneNode2T(0), SceneNodeTangents(0)
        , AllColorsControl(0), ButtonLighting(0), InfoLighting(0), ComboMaterial(0), TextureControl1(0), TextureControl2(0), ControlVertexColors(0)
    {
    }

    // Destructor
    virtual ~SMeshNodeControl()
    {
        if ( TextureControl1 )
            TextureControl1->drop();
        if ( TextureControl2 )
            TextureControl2->drop();
        if ( ControlVertexColors )
            ControlVertexColors->drop();
        if ( AllColorsControl )
            AllColorsControl->drop();
    }

    void init(scene::IMeshSceneNode* node, IrrlichtDevice * device, const core::position2d<s32> & pos, const wchar_t * description)
    {
        if ( Initialized || !node || !device) // initializing twice or with invalid data not allowed
            return;

        Driver = device->getVideoDriver ();
        gui::IGUIEnvironment* guiEnv = device->getGUIEnvironment();
        scene::ISceneManager* smgr = device->getSceneManager();
        MeshManipulator = smgr->getMeshManipulator();

        SceneNode = node;
        scene::IMeshManipulator * meshManip = smgr->getMeshManipulator();

        scene::IMesh * mesh2T = meshManip->createMeshWith2TCoords(node->getMesh());
        SceneNode2T = smgr->addMeshSceneNode(mesh2T, 0, -1, SceneNode->getPosition(), SceneNode->getRotation(), SceneNode->getScale() );
        mesh2T->drop();

        scene::IMesh * meshTangents = meshManip->createMeshWithTangents(node->getMesh(), false, false, false);
        SceneNodeTangents = smgr->addMeshSceneNode(meshTangents, 0, -1
                                            , SceneNode->getPosition(), SceneNode->getRotation(), SceneNode->getScale() );
        meshTangents->drop();

        video::SMaterial & material = SceneNode->getMaterial(0);
        material.Lighting = true;
        AllColorsControl = new CAllColorsControl(guiEnv, pos, description, true, guiEnv->getRootGUIElement());
        AllColorsControl->setColorsToMaterialColors(material);

        core::rect<s32> rectBtn(pos + core::position2d<s32>(0, 320), core::dimension2d<s32>(60, 15));
        ButtonLighting = guiEnv->addButton (rectBtn, 0, -1, L"Lighting");
        ButtonLighting->setIsPushButton(true);
        ButtonLighting->setPressed(material.Lighting);
        core::rect<s32> rectInfo( rectBtn.LowerRightCorner.X, rectBtn.UpperLeftCorner.Y, rectBtn.LowerRightCorner.X+40, rectBtn.UpperLeftCorner.Y+15 );
        InfoLighting = guiEnv->addStaticText(L"", rectInfo, true, false );
        InfoLighting->setTextAlignment(gui::EGUIA_CENTER, gui::EGUIA_CENTER );

        core::rect<s32> rectCombo(pos.X, rectBtn.LowerRightCorner.Y, pos.X+100, rectBtn.LowerRightCorner.Y+15);
        ComboMaterial = guiEnv->addComboBox (rectCombo);
        for ( int i=0; i <= (int)video::EMT_ONETEXTURE_BLEND; ++i )
        {
            ComboMaterial->addItem( core::stringw(video::sBuiltInMaterialTypeNames[i]).c_str() );
        }
        ComboMaterial->setSelected( (s32)material.MaterialType );

        core::position2d<s32> posTex(rectCombo.UpperLeftCorner.X,rectCombo.LowerRightCorner.Y);
        TextureControl1 = new CTextureControl(guiEnv, Driver, posTex, guiEnv->getRootGUIElement());
        posTex.Y += 15;
        TextureControl2 = new CTextureControl(guiEnv, Driver, posTex, guiEnv->getRootGUIElement());

        core::position2d<s32> posVertexColors( posTex.X, posTex.Y + 15);
        ControlVertexColors = new CColorControl( guiEnv, posVertexColors, L"Vertex colors", guiEnv->getRootGUIElement());

        video::S3DVertex * vertices =  (video::S3DVertex *)node->getMesh()->getMeshBuffer(0)->getVertices();
        if ( vertices )
        {
            ControlVertexColors->setColor(vertices[0].Color);
        }

        Initialized = true;
    }

    void update()
    {
        if ( !Initialized )
            return;

        video::SMaterial & material = SceneNode->getMaterial(0);
        video::SMaterial & material2T = SceneNode2T->getMaterial(0);
        video::SMaterial & materialTangents = SceneNodeTangents->getMaterial(0);

        s32 selectedMaterial = ComboMaterial->getSelected();
        if ( selectedMaterial >= (s32)video::EMT_SOLID && selectedMaterial <= (s32)video::EMT_ONETEXTURE_BLEND)
        {
            video::E_VERTEX_TYPE vertexType = getVertexTypeForMaterialType((video::E_MATERIAL_TYPE)selectedMaterial);
            switch ( vertexType )
            {
                case video::EVT_STANDARD:
                    material.MaterialType = (video::E_MATERIAL_TYPE)selectedMaterial;
                    SceneNode->setVisible(true);
                    SceneNode2T->setVisible(false);
                    SceneNodeTangents->setVisible(false);
                    break;
                case video::EVT_2TCOORDS:
                    material2T.MaterialType = (video::E_MATERIAL_TYPE)selectedMaterial;
                    SceneNode->setVisible(false);
                    SceneNode2T->setVisible(true);
                    SceneNodeTangents->setVisible(false);
                    break;
                case video::EVT_TANGENTS:
                    materialTangents.MaterialType = (video::E_MATERIAL_TYPE)selectedMaterial;
                    SceneNode->setVisible(false);
                    SceneNode2T->setVisible(false);
                    SceneNodeTangents->setVisible(true);
                    break;
            }
        }

        updateMaterial(material);
        updateMaterial(material2T);
        updateMaterial(materialTangents);

        if ( ButtonLighting->isPressed() )
            InfoLighting->setText(L"on");
        else
            InfoLighting->setText(L"off");

        AllColorsControl->resetDirty();
        TextureControl1->resetDirty();
        TextureControl2->resetDirty();
        ControlVertexColors->resetDirty();
    }

    void updateTextures()
    {
        TextureControl1->updateTextures(Driver);
        TextureControl2->updateTextures(Driver);
    }

protected:

    void updateMaterial(video::SMaterial & material)
    {
        AllColorsControl->updateMaterialColors(material);
        material.Lighting = ButtonLighting->isPressed();
        if ( TextureControl1->isDirty() )
        {
            material.TextureLayer[0].Texture = Driver->getTexture( io::path(TextureControl1->getSelectedTextureName()) );
        }
        if ( TextureControl2->isDirty() )
        {
            material.TextureLayer[1].Texture = Driver->getTexture( io::path(TextureControl2->getSelectedTextureName()) );
        }
        if ( ControlVertexColors->isDirty() )
        {
            MeshManipulator->setVertexColors (SceneNode->getMesh(), ControlVertexColors->getColor());
            MeshManipulator->setVertexColors (SceneNode2T->getMesh(), ControlVertexColors->getColor());
            MeshManipulator->setVertexColors (SceneNodeTangents->getMesh(), ControlVertexColors->getColor());
        }
    }

    bool Initialized;
    video::IVideoDriver *       Driver;
    scene::IMeshManipulator*    MeshManipulator;
    scene::IMeshSceneNode*      SceneNode;
    scene::IMeshSceneNode*      SceneNode2T;
    scene::IMeshSceneNode*      SceneNodeTangents;
    CAllColorsControl*          AllColorsControl;
    gui::IGUIButton *           ButtonLighting;
    gui::IGUIStaticText*        InfoLighting;
    gui::IGUIComboBox *         ComboMaterial;
    CTextureControl*            TextureControl1;
    CTextureControl*            TextureControl2;
    CColorControl*              ControlVertexColors;
};

Control to allow setting the color values of a lightscenenode.

struct SLightNodeControl
{
    // constructor
    SLightNodeControl() : Initialized(false), SceneNode(0), AllColorsControl(0)
    {
    }

    virtual ~SLightNodeControl()
    {
        if ( AllColorsControl )
            AllColorsControl->drop();
    }

    void init(scene::ILightSceneNode* node, gui::IGUIEnvironment* guiEnv, const core::position2d<s32> & pos, const wchar_t * description)
    {
        if ( Initialized || !node || !guiEnv) // initializing twice or with invalid data not allowed
            return;
        SceneNode = node;
        AllColorsControl = new CAllColorsControl(guiEnv, pos, description, false, guiEnv->getRootGUIElement());
        const video::SLight & lightData = SceneNode->getLightData();
        AllColorsControl->setColorsToLightDataColors(lightData);
        Initialized = true;
    }

    void update()
    {
        if ( !Initialized )
            return;

        video::SLight & lightData = SceneNode->getLightData();
        AllColorsControl->updateLightColors(lightData);
    }

protected:
    bool Initialized;
    scene::ILightSceneNode* SceneNode;
    CAllColorsControl* AllColorsControl;
};

Application configuration

struct SConfig
{
    SConfig()
    : RenderInBackground(true)
    , DriverType(video::EDT_BURNINGSVIDEO)
    , ScreenSize(640, 480)
    {
    }

    bool RenderInBackground;
    video::E_DRIVER_TYPE DriverType;
    core::dimension2d<u32> ScreenSize;
};

Main application class

class CApp : public IEventReceiver
{
    friend int main(int argc, char *argv[]);

public:
    // constructor
    CApp()
    : IsRunning(false)
    , Device(0)
    , Camera(0)
    , GlobalAmbient(0)
    {
    }

    // destructor
    ~CApp()
    {
    }

    // stop running - will quit at end of mainloop
    void stopApp()
    {
        IsRunning = false;
    }

    // Event handler
    virtual bool OnEvent(const SEvent &event)
    {
        if (event.EventType == EET_GUI_EVENT)
        {
            gui::IGUIEnvironment* env = Device->getGUIEnvironment();

            switch(event.GUIEvent.EventType)
            {
                case gui::EGET_MENU_ITEM_SELECTED:
                {
                    gui::IGUIContextMenu* menu = (gui::IGUIContextMenu*)event.GUIEvent.Caller;
                    s32 id = menu->getItemCommandId(menu->getSelectedItem());

                    switch(id)
                    {
                        case GUI_ID_OPEN_TEXTURE: // File -> Open Texture
                            env->addFileOpenDialog(L"Please select a texture file to open");
                        break;
                        case GUI_ID_QUIT: // File -> Quit
                            stopApp();
                        break;
                    }
                }
                break;

                case gui::EGET_FILE_SELECTED:
                {
                    // load the model file, selected in the file open dialog
                    gui::IGUIFileOpenDialog* dialog =
                        (gui::IGUIFileOpenDialog*)event.GUIEvent.Caller;
                    loadTexture(io::path(dialog->getFileName()).c_str());
                }
                break;

                default:
                break;
            }
        }

        return false;
    }

protected:

    // Application initialization
    // returns true when it was successful initialized, otherwise false.
    bool init(int argc, char *argv[])
    {
        // ask user for driver
        Config.DriverType=driverChoiceConsole();
        if (Config.DriverType==video::EDT_COUNT)
            return false;

        // create the device with the settings from our config
        Device = createDevice(Config.DriverType, Config.ScreenSize);
        if (!Device)
            return false;
        Device->setWindowCaption( DriverTypeNames[Config.DriverType] );
        Device->setEventReceiver(this);

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

        // set a nicer font
        gui::IGUISkin* skin = guiEnv->getSkin();
        gui::IGUIFont* font = guiEnv->getFont("../../media/fonthaettenschweiler.bmp");
        if (font)
            skin->setFont(font);

        // remove some alpha value because it makes those menus harder to read otherwise
        video::SColor col3dHighLight( skin->getColor(gui::EGDC_APP_WORKSPACE) );
        col3dHighLight.setAlpha(255);
        video::SColor colHighLight( col3dHighLight );
        skin->setColor(gui::EGDC_HIGH_LIGHT, colHighLight );
        skin->setColor(gui::EGDC_3D_HIGH_LIGHT, col3dHighLight );

        // Add some textures which are useful to test material settings
        createDefaultTextures(driver);

        // create a menu
        gui::IGUIContextMenu * menuBar = guiEnv->addMenu();
        menuBar->addItem(L"File", -1, true, true);

        gui::IGUIContextMenu* subMenuFile = menuBar->getSubMenu(0);
        subMenuFile->addItem(L"Open texture ...", GUI_ID_OPEN_TEXTURE);
        subMenuFile->addSeparator();
        subMenuFile->addItem(L"Quit", GUI_ID_QUIT);

        // a static camera
        Camera = smgr->addCameraSceneNode (0, core::vector3df(0, 0, 0),
                                            core::vector3df(0, 0, 100),
                                            -1);

        // add the nodes which are used to show the materials
        scene::IMeshSceneNode* nodeL = smgr->addCubeSceneNode (30.0f, 0, -1,
                                           core::vector3df(-35, 0, 100),
                                           core::vector3df(0, 0, 0),
                                           core::vector3df(1.0f, 1.0f, 1.0f));
        NodeLeft.init( nodeL, Device, core::position2d<s32>(10,20), L"left node" );

        scene::IMeshSceneNode* nodeR = smgr->addCubeSceneNode (30.0f, 0, -1,
                                           core::vector3df(35, 0, 100),
                                           core::vector3df(0, 0, 0),
                                           core::vector3df(1.0f, 1.0f, 1.0f));
        NodeRight.init( nodeR, Device, core::position2d<s32>(530,20), L"right node" );

        // add one light
        scene::ILightSceneNode* nodeLight = smgr->addLightSceneNode(0, core::vector3df(0, 0, 0),
                                                        video::SColorf(1.0f, 1.0f, 1.0f),
                                                        100.0f);
        LightControl.init(nodeLight, guiEnv, core::position2d<s32>(270,20), L"light" );

        // one large cube around everything. That's mainly to make the light more obvious.
        scene::IMeshSceneNode* backgroundCube = smgr->addCubeSceneNode (200.0f, 0, -1, core::vector3df(0, 0, 0),
                                           core::vector3df(45, 0, 0),
                                           core::vector3df(1.0f, 1.0f, 1.0f));
        backgroundCube->getMaterial(0).BackfaceCulling = false;         // we are within the cube, so we have to disable backface culling to see it
        backgroundCube->getMaterial(0).EmissiveColor.set(255,50,50,50); // we keep some self lighting to keep texts visible

        // set the ambient light value
        GlobalAmbient = new CColorControl( guiEnv, core::position2d<s32>(270, 300), L"global ambient", guiEnv->getRootGUIElement());
        GlobalAmbient->setColor( smgr->getAmbientLight().toSColor() );

        return true;
    }

    // Update one frame
    bool update()
    {
        using namespace irr;

        video::IVideoDriver* videoDriver =  Device->getVideoDriver();
        if ( !Device->run() )
            return false;

        if ( Device->isWindowActive() || Config.RenderInBackground )
        {
            gui::IGUIEnvironment* guiEnv = Device->getGUIEnvironment();
            scene::ISceneManager* smgr = Device->getSceneManager();
            gui::IGUISkin * skin = guiEnv->getSkin();

            // update our controls
            NodeLeft.update();
            NodeRight.update();
            LightControl.update();

            // update ambient light settings
            if ( GlobalAmbient->isDirty() )
            {
                smgr->setAmbientLight( GlobalAmbient->getColor() );
                GlobalAmbient->resetDirty();
            }

            // draw everything
            video::SColor bkColor( skin->getColor(gui::EGDC_APP_WORKSPACE) );
            videoDriver->beginScene(true, true, bkColor);

            smgr->drawAll();
            guiEnv->drawAll();

            videoDriver->endScene();
        }

        return true;
    }

    // Run the application. Our main loop.
    void run()
    {
        IsRunning = true;

        if ( !Device )
            return;

        // main application loop
        while(IsRunning)
        {
            if ( !update() )
                break;

            Device->sleep( 5 );
        }
    }

    // Close down the application
    void quit()
    {
        IsRunning = false;
        GlobalAmbient->drop();
        GlobalAmbient = NULL;
        if ( Device )
        {
            Device->closeDevice();
            Device->drop();
            Device = NULL;
        }
    }

    // Create some useful textures.
    // Note that the function put readability over speed, you shouldn't use setPixel at runtime but for initialization it's nice.
    void createDefaultTextures(video::IVideoDriver * driver)
    {
        const u32 width = 256;
        const u32 height = 256;
        video::IImage * imageA8R8G8B8 = driver->createImage (video::ECF_A8R8G8B8, core::dimension2d<u32>(width, height));
        if ( !imageA8R8G8B8 )
            return;
        const u32 pitch = imageA8R8G8B8->getPitch();

        // some nice square-pattern with 9 typical colors
        for ( u32 y = 0; y < height; ++ y )
        {
            for ( u32 x = 0; x < pitch; ++x )
            {
                if ( y < height/3 )
                {
                    if ( x < width/3 )
                        imageA8R8G8B8->setPixel (x, y, SCOL_BLACK);
                    else if ( x < 2*width/3 )
                        imageA8R8G8B8->setPixel (x, y, SCOL_BLUE);
                    else
                        imageA8R8G8B8->setPixel (x, y, SCOL_CYAN);
                }
                else if ( y < 2*height/3 )
                {
                    if ( x < width/3 )
                        imageA8R8G8B8->setPixel (x, y, SCOL_GRAY);
                    else if ( x < 2*width/3 )
                        imageA8R8G8B8->setPixel (x, y, SCOL_GREEN);
                    else
                        imageA8R8G8B8->setPixel (x, y, SCOL_MAGENTA);
                }
                else
                {
                    if ( x < width/3 )
                        imageA8R8G8B8->setPixel (x, y, SCOL_RED);
                    else if ( x < 2*width/3 )
                        imageA8R8G8B8->setPixel (x, y, SCOL_YELLOW);
                    else
                        imageA8R8G8B8->setPixel (x, y, SCOL_WHITE);
                }
            }
        }
        driver->addTexture (io::path("CARO_A8R8G8B8"), imageA8R8G8B8);

        // all white
        imageA8R8G8B8->fill(SCOL_WHITE);
        driver->addTexture (io::path("WHITE_A8R8G8B8"), imageA8R8G8B8);

        // all black
        imageA8R8G8B8->fill(SCOL_BLACK);
        driver->addTexture (io::path("BLACK_A8R8G8B8"), imageA8R8G8B8);

        // gray-scale
        for ( u32 y = 0; y < height; ++ y )
        {
            for ( u32 x = 0; x < pitch; ++x )
            {
                imageA8R8G8B8->setPixel (x, y, video::SColor(y, x,x,x) );
            }
        }
        driver->addTexture (io::path("GRAYSCALE_A8R8G8B8"), imageA8R8G8B8);

        imageA8R8G8B8->drop();
    }

    // Load a texture and make sure nodes know it when more textures are available.
    void loadTexture(const io::path &name)
    {
        Device->getVideoDriver()->getTexture(name);
        NodeLeft.updateTextures();
        NodeRight.updateTextures();
    }

private:
    SConfig                     Config;
    volatile bool               IsRunning;
    IrrlichtDevice *            Device;
    scene::ICameraSceneNode *   Camera;
    SMeshNodeControl            NodeLeft;
    SMeshNodeControl            NodeRight;
    SLightNodeControl           LightControl;
    CColorControl *             GlobalAmbient;
};

A very short main as we do everything else in classes.

int main(int argc, char *argv[])
{
    CApp APP;

    if ( !APP.init(argc, argv) )
    {
        printf("init failed\n");
        return 1;
    }

    APP.run();
    APP.quit();

    return 0;
}