Ogre的SampleBrowser效果

最新的OGRE把例子都做为插件，在SampleBrowser中浏览。

那个浏览的界面做的真是好看，操作起来也不错，于是想把他的那个Sample的缩略图显示拿出来，以后做为游戏关卡的选择界面。

主要用的还是OGRE中的Overlay。

声明：

        // ui function
    void SetupUI();
    void SetupLevelMenu();
    void UpdateUI(double timeSinceLastFrame);

    // for ui
    OgreBites::SelectMenu* m_pMenu;
    std::vector<Ogre::OverlayContainer*> m_Thumbs;  // sample thumbnails
    Ogre::StringVector m_SampleNames;
    Ogre::Real m_CarouselPlace;

定义：

    m_SampleNames.push_back("thumb_bezier");
    m_SampleNames.push_back("thumb_bsp");
    m_SampleNames.push_back("thumb_bump");
    m_SampleNames.push_back("thumb_camtrack");
    m_SampleNames.push_back("thumb_cel");

void CMenuState::SetupLevelMenu()
{
// create template material for sample thumbnails
    Ogre::MaterialPtr thumbMat = Ogre::MaterialManager::getSingleton().create("SampleThumbnail", "Essential");
    thumbMat->getTechnique(0)->getPass(0)->createTextureUnitState();
    Ogre::MaterialPtr templateMat = Ogre::MaterialManager::getSingleton().getByName("SampleThumbnail");

    Ogre::StringVector::iterator itr;

    for (itr = m_SampleNames.begin(); itr != m_SampleNames.end(); itr++)
    {

        Ogre::String name = "SampleThumb" + Ogre::StringConverter::toString(m_Thumbs.size() + 1);

        // clone a new material for sample thumbnail
        Ogre::MaterialPtr newMat = templateMat->clone(name);

        Ogre::TextureUnitState* tus = newMat->getTechnique(0)->getPass(0)->getTextureUnitState(0);
        if (Ogre::ResourceGroupManager::getSingleton().resourceExists("Essential", *itr + ".png"))
            tus->setTextureName(*itr + ".png");
        else 
            tus->setTextureName("thumb_error.png");

        Ogre::BorderPanelOverlayElement* bp = (Ogre::BorderPanelOverlayElement*)
            Ogre::OverlayManager::getSingleton().createOverlayElementFromTemplate("SdkTrays/Picture", "BorderPanel", (*itr));

        //Ogre::ResourceGroupManager::getSingletonPtr()->loadResourceGroup("Essential");

        bp->setHorizontalAlignment(Ogre::GHA_RIGHT);
        bp->setVerticalAlignment(Ogre::GVA_CENTER);
        bp->setMaterialName(name);
        COgreFramework::getSingletonPtr()->m_pTrayMgr->getTraysLayer()->add2D(bp);

        m_Thumbs.push_back(bp);
    }
}

更新：

void CMenuState::UpdateUI(double timeSinceLastFrame)
{
    // makes the carousel spin smoothly toward its right position
    Ogre::Real carouselOffset = m_pMenu->getSelectionIndex() - m_CarouselPlace;
    if ((carouselOffset <= 0.001) && (carouselOffset >= -0.001)) m_CarouselPlace = m_pMenu->getSelectionIndex();
    else m_CarouselPlace += carouselOffset * Ogre::Math::Clamp<Ogre::Real>(timeSinceLastFrame * 0.015, -1.0, 1.0);

    for (int i = 0; i < (int)m_Thumbs.size(); i++)
    {
        Ogre::Real thumbOffset = m_CarouselPlace - i;
        Ogre::Real phase = (thumbOffset / 2.0) - 2.8;

        if (thumbOffset < -5 || thumbOffset > 4)    // prevent thumbnails from wrapping around in a circle
        {
            m_Thumbs[i]->hide();
            continue;
        }
        else m_Thumbs[i]->show();

        Ogre::Real left = Ogre::Math::Cos(phase) * 200.0;
        Ogre::Real top = Ogre::Math::Sin(phase) * 200.0;
        Ogre::Real scale = 1.0 / Ogre::Math::Pow((Ogre::Math::Abs(thumbOffset) + 1.0), 0.75);

        Ogre::BorderPanelOverlayElement* frame =
            (Ogre::BorderPanelOverlayElement*)m_Thumbs[i]->getChildIterator().getNext();

        m_Thumbs[i]->setDimensions(128.0 * scale, 96.0 * scale);
        frame->setDimensions(m_Thumbs[i]->getWidth() + 16.0, m_Thumbs[i]->getHeight() + 16.0);
        m_Thumbs[i]->setPosition((int)(left - 80.0 - (m_Thumbs[i]->getWidth() / 2.0)),
            (int)(top - 5.0 - (m_Thumbs[i]->getHeight() / 2.0)));

        if (i == m_pMenu->getSelectionIndex()) frame->setBorderMaterialName("SdkTrays/Frame/Over");
        else frame->setBorderMaterialName("SdkTrays/Frame");
    }
}

最后加上鼠标的滑轮操作：

bool CMenuState::mouseMoved(const OIS::MouseEvent &evt)
{

    OIS::MouseState state = evt.state;
    OIS::MouseEvent orientedEvt((OIS::Object*)evt.device, state);

    if (orientedEvt.state.Z.rel != 0 && m_pMenu->getNumItems() != 0)
    {
        int newIndex = m_pMenu->getSelectionIndex() - orientedEvt.state.Z.rel / Ogre::Math::Abs(orientedEvt.state.Z.rel);
        m_pMenu->selectItem(Ogre::Math::Clamp<int>(newIndex, 0, m_pMenu->getNumItems() - 1));
    }

    if (COgreFramework::getSingletonPtr()->m_pTrayMgr->injectMouseMove(evt))
        return true;

    return true;
}

效果图：