This file is indexed.

/usr/share/openscenegraph/examples/osgqfont/osgqfont.cpp is in openscenegraph-examples 3.2.0~rc1-4.

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/* OpenSceneGraph example, osgtext.
*
*  Permission is hereby granted, free of charge, to any person obtaining a copy
*  of this software and associated documentation files (the "Software"), to deal
*  in the Software without restriction, including without limitation the rights
*  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
*  copies of the Software, and to permit persons to whom the Software is
*  furnished to do so, subject to the following conditions:
*
*  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
*  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
*  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
*  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
*  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
*  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
*  THE SOFTWARE.
*/

#include <QApplication>
#include <QGridLayout>
#include <QWidget>

#include <osgQt/GraphicsWindowQt>
#include <osgQt/QFontImplementation>

#include <osgDB/ReadFile>
#include <osgDB/WriteFile>
#include <osgDB/Registry>

#include <osgGA/StateSetManipulator>
#include <osgGA/TrackballManipulator>
#include <osgViewer/CompositeViewer>
#include <osgViewer/ViewerEventHandlers>

#include <osg/Geode>
#include <osg/Camera>
#include <osg/ShapeDrawable>
#include <osg/Sequence>
#include <osg/PolygonMode>

#include <osgText/Font>
#include <osgText/Text>

osg::Group* createHUDText()
{

    osg::Group* rootNode = new osg::Group;

    osgText::Font* font = new osgText::Font(new osgQt::QFontImplementation(QFont("Arial")));

    osg::Geode* geode  = new osg::Geode;
    rootNode->addChild(geode);

    float windowHeight = 1024.0f;
    float windowWidth = 1280.0f;
    float margin = 50.0f;


////////////////////////////////////////////////////////////////////////////////////////////////////////
//    
// Examples of how to set up different text layout
//

    osg::Vec4 layoutColor(1.0f,1.0f,0.0f,1.0f);
    float layoutCharacterSize = 20.0f;    
    
    {
        osgText::Text* text = new osgText::Text;
        text->setFont(font);
        text->setColor(layoutColor);
        text->setCharacterSize(layoutCharacterSize);
        text->setPosition(osg::Vec3(margin,windowHeight-margin,0.0f));

        // the default layout is left to right, typically used in languages
        // originating from europe such as English, French, German, Spanish etc..
        text->setLayout(osgText::Text::LEFT_TO_RIGHT);

        text->setText("text->setLayout(osgText::Text::LEFT_TO_RIGHT);");
        geode->addDrawable(text);
    }

    {
        osgText::Text* text = new osgText::Text;
        text->setFont(font);
        text->setColor(layoutColor);
        text->setCharacterSize(layoutCharacterSize);
        text->setPosition(osg::Vec3(windowWidth-margin,windowHeight-margin,0.0f));

        // right to left layouts would be used for hebrew or arabic fonts.
        text->setLayout(osgText::Text::RIGHT_TO_LEFT);
        text->setAlignment(osgText::Text::RIGHT_BASE_LINE);

        text->setText("text->setLayout(osgText::Text::RIGHT_TO_LEFT);");
        geode->addDrawable(text);
    }

    {
        osgText::Text* text = new osgText::Text;
        text->setFont(font);
        text->setColor(layoutColor);
        text->setPosition(osg::Vec3(margin,windowHeight-margin,0.0f));
        text->setCharacterSize(layoutCharacterSize);

        // vertical font layout would be used for asian fonts.
        text->setLayout(osgText::Text::VERTICAL);

        text->setText("text->setLayout(osgText::Text::VERTICAL);");
        geode->addDrawable(text);
    }
    
    
////////////////////////////////////////////////////////////////////////////////////////////////////////
//    
// Examples of how to set up different font resolution
//

    osg::Vec4 fontSizeColor(0.0f,1.0f,1.0f,1.0f);
    float fontSizeCharacterSize = 30;
    
    osg::Vec3 cursor = osg::Vec3(margin*2,windowHeight-margin*2,0.0f);
    
    {
        osgText::Text* text = new osgText::Text;
        text->setFont(font);
        text->setColor(fontSizeColor);
        text->setCharacterSize(fontSizeCharacterSize);
        text->setPosition(cursor);
        
        // use text that uses 10 by 10 texels as a target resolution for fonts.
        text->setFontResolution(10,10); // blocky but small texture memory usage
        
        text->setText("text->setFontResolution(10,10); // blocky but small texture memory usage");
        geode->addDrawable(text);
    }
    
    cursor.y() -= fontSizeCharacterSize;
    {
        osgText::Text* text = new osgText::Text;
        text->setFont(font);
        text->setColor(fontSizeColor);
        text->setCharacterSize(fontSizeCharacterSize);
        text->setPosition(cursor);
        
        // use text that uses 20 by 20 texels as a target resolution for fonts.
        text->setFontResolution(20,20); // smoother but higher texture memory usage (but still quite low).
        
        text->setText("text->setFontResolution(20,20); // smoother but higher texture memory usage (but still quite low).");
        geode->addDrawable(text);
    }
    
    cursor.y() -= fontSizeCharacterSize;
    {
        osgText::Text* text = new osgText::Text;
        text->setFont(font);
        text->setColor(fontSizeColor);
        text->setCharacterSize(fontSizeCharacterSize);
        text->setPosition(cursor);
        
        // use text that uses 40 by 40 texels as a target resolution for fonts.
        text->setFontResolution(40,40); // even smoother but again higher texture memory usage.
        
        text->setText("text->setFontResolution(40,40); // even smoother but again higher texture memory usage.");
        geode->addDrawable(text);
    }


////////////////////////////////////////////////////////////////////////////////////////////////////////
//    
// Examples of how to set up different sized text
//

    osg::Vec4 characterSizeColor(1.0f,0.0f,1.0f,1.0f);
    
    cursor.y() -= fontSizeCharacterSize*2.0f;
    
    {
        osgText::Text* text = new osgText::Text;
        text->setFont(font);
        text->setColor(characterSizeColor);
        text->setFontResolution(20,20);
        text->setPosition(cursor);
        
        // use text that is 20 units high.
        text->setCharacterSize(20); // small
        
        text->setText("text->setCharacterSize(20.0f); // small");
        geode->addDrawable(text);
    }
    
    cursor.y() -= 30.0f;
    {
        osgText::Text* text = new osgText::Text;
        text->setFont(font);
        text->setColor(characterSizeColor);
        text->setFontResolution(30,30);
        text->setPosition(cursor);
        
        // use text that is 30 units high.
        text->setCharacterSize(30.0f); // medium
        
        text->setText("text->setCharacterSize(30.0f); // medium");
        geode->addDrawable(text);
    }
    
    cursor.y() -= 50.0f;
    {
        osgText::Text* text = new osgText::Text;
        text->setFont(font);
        text->setColor(characterSizeColor);
        text->setFontResolution(40,40);
        text->setPosition(cursor);
        
        // use text that is 60 units high.
        text->setCharacterSize(60.0f); // large
        
        text->setText("text->setCharacterSize(60.0f); // large");
        geode->addDrawable(text);
    }


////////////////////////////////////////////////////////////////////////////////////////////////////////
//    
// Examples of how to set up different alignments
//

    osg::Vec4 alignmentSizeColor(0.0f,1.0f,0.0f,1.0f);
    float alignmentCharacterSize = 25.0f;
    cursor.x() = 640;
    cursor.y() = margin*4.0f;
    
    typedef std::pair<osgText::Text::AlignmentType,std::string> AlignmentPair;
    typedef std::vector<AlignmentPair> AlignmentList;
    AlignmentList alignmentList;
    alignmentList.push_back(AlignmentPair(osgText::Text::LEFT_TOP,"text->setAlignment(\nosgText::Text::LEFT_TOP);"));
    alignmentList.push_back(AlignmentPair(osgText::Text::LEFT_CENTER,"text->setAlignment(\nosgText::Text::LEFT_CENTER);"));
    alignmentList.push_back(AlignmentPair(osgText::Text::LEFT_BOTTOM,"text->setAlignment(\nosgText::Text::LEFT_BOTTOM);"));
    alignmentList.push_back(AlignmentPair(osgText::Text::CENTER_TOP,"text->setAlignment(\nosgText::Text::CENTER_TOP);"));
    alignmentList.push_back(AlignmentPair(osgText::Text::CENTER_CENTER,"text->setAlignment(\nosgText::Text::CENTER_CENTER);"));
    alignmentList.push_back(AlignmentPair(osgText::Text::CENTER_BOTTOM,"text->setAlignment(\nosgText::Text::CENTER_BOTTOM);"));
    alignmentList.push_back(AlignmentPair(osgText::Text::RIGHT_TOP,"text->setAlignment(\nosgText::Text::RIGHT_TOP);"));
    alignmentList.push_back(AlignmentPair(osgText::Text::RIGHT_CENTER,"text->setAlignment(\nosgText::Text::RIGHT_CENTER);"));
    alignmentList.push_back(AlignmentPair(osgText::Text::RIGHT_BOTTOM,"text->setAlignment(\nosgText::Text::RIGHT_BOTTOM);"));
    alignmentList.push_back(AlignmentPair(osgText::Text::LEFT_BASE_LINE,"text->setAlignment(\nosgText::Text::LEFT_BASE_LINE);"));
    alignmentList.push_back(AlignmentPair(osgText::Text::CENTER_BASE_LINE,"text->setAlignment(\nosgText::Text::CENTER_BASE_LINE);"));
    alignmentList.push_back(AlignmentPair(osgText::Text::RIGHT_BASE_LINE,"text->setAlignment(\nosgText::Text::RIGHT_BASE_LINE);"));
    alignmentList.push_back(AlignmentPair(osgText::Text::LEFT_BOTTOM_BASE_LINE,"text->setAlignment(\nosgText::Text::LEFT_BOTTOM_BASE_LINE);"));
    alignmentList.push_back(AlignmentPair(osgText::Text::CENTER_BOTTOM_BASE_LINE,"text->setAlignment(\nosgText::Text::CENTER_BOTTOM_BASE_LINE);"));
    alignmentList.push_back(AlignmentPair(osgText::Text::RIGHT_BOTTOM_BASE_LINE,"text->setAlignment(\nosgText::Text::RIGHT_BOTTOM_BASE_LINE);"));


    osg::Sequence* sequence = new osg::Sequence;
    {
        for(AlignmentList::iterator itr=alignmentList.begin();
            itr!=alignmentList.end();
            ++itr)
        {
            osg::Geode* alignmentGeode = new osg::Geode;
            sequence->addChild(alignmentGeode);
            sequence->setTime(sequence->getNumChildren(), 1.0f);

            osgText::Text* text = new osgText::Text;
            text->setFont(font);
            text->setColor(alignmentSizeColor);
            text->setCharacterSize(alignmentCharacterSize);
            text->setPosition(cursor);
            text->setDrawMode(osgText::Text::TEXT|osgText::Text::ALIGNMENT|osgText::Text::BOUNDINGBOX);
            
            text->setAlignment(itr->first);
            text->setText(itr->second);
            
            alignmentGeode->addDrawable(text);


        }
        
    }

    sequence->setMode(osg::Sequence::START);
    sequence->setInterval(osg::Sequence::LOOP, 0, -1);
    sequence->setDuration(1.0f, -1);
    
    rootNode->addChild(sequence);


////////////////////////////////////////////////////////////////////////////////////////////////////////
//    
// Examples of how to set up different fonts...
//

    cursor.x() = margin*2.0f;
    cursor.y() = margin*2.0f;
    
    osg::Vec4 fontColor(1.0f,0.5f,0.0f,1.0f);
    float fontCharacterSize = 20.0f;
    float spacing = 40.0f;
    
    {
        osgText::Text* text = new osgText::Text;
        text->setColor(fontColor);
        text->setPosition(cursor);
        text->setCharacterSize(fontCharacterSize);
        
        text->setFont(0);
        text->setText("text->setFont(0); // inbuilt font.");
        geode->addDrawable(text);

        cursor.x() = text->getBound().xMax() + spacing ;
    }
    
    {
        osgText::Font* arial = new osgText::Font(new osgQt::QFontImplementation(QFont("Arial")));

        osgText::Text* text = new osgText::Text;
        text->setColor(fontColor);
        text->setPosition(cursor);
        text->setCharacterSize(fontCharacterSize);
        
        text->setFont(arial);
        text->setText(arial!=0?
                      "text->setFont(\"fonts/arial.ttf\");":
                      "unable to load \"fonts/arial.ttf\"");
        geode->addDrawable(text);

        cursor.x() = text->getBound().xMax() + spacing ;
    }
    
    {
        osgText::Font* times = new osgText::Font(new osgQt::QFontImplementation(QFont("Times")));

        osgText::Text* text = new osgText::Text;
        text->setColor(fontColor);
        text->setPosition(cursor);
        text->setCharacterSize(fontCharacterSize);
        
        geode->addDrawable(text);
        text->setFont(times);
        text->setText(times!=0?
                      "text->setFont(\"fonts/times.ttf\");":
                      "unable to load \"fonts/times.ttf\"");

        cursor.x() = text->getBound().xMax() + spacing ;
    }
    
    cursor.x() = margin*2.0f;
    cursor.y() = margin;

    {
        osgText::Font* dirtydoz = new osgText::Font(new osgQt::QFontImplementation(QFont("Times")));

        osgText::Text* text = new osgText::Text;
        text->setColor(fontColor);
        text->setPosition(cursor);
        text->setCharacterSize(fontCharacterSize);
        
        text->setFont(dirtydoz);
        text->setText(dirtydoz!=0?
                      "text->setFont(\"fonts/dirtydoz.ttf\");":
                      "unable to load \"fonts/dirtydoz.ttf\"");
        geode->addDrawable(text);

        cursor.x() = text->getBound().xMax() + spacing ;
    }
    
    {
        osgText::Font* fudd = new osgText::Font(new osgQt::QFontImplementation(QFont("Times")));
    
        osgText::Text* text = new osgText::Text;
        text->setColor(fontColor);
        text->setPosition(cursor);
        text->setCharacterSize(fontCharacterSize);
        
        text->setFont(fudd);
        text->setText(fudd!=0?
                      "text->setFont(\"fonts/fudd.ttf\");":
                      "unable to load \"fonts/fudd.ttf\"");
        geode->addDrawable(text);

        cursor.x() = text->getBound().xMax() + spacing ;
    }
            
    return rootNode;    
}




// create text which sits in 3D space such as would be inserted into a normal model
osg::Group* create3DText(const osg::Vec3& center,float radius)
{

    osg::Geode* geode  = new osg::Geode;

////////////////////////////////////////////////////////////////////////////////////////////////////////
//    
// Examples of how to set up axis/orientation alignments
//

    float characterSize=radius*0.2f;
    
    osg::Vec3 pos(center.x()-radius*.5f,center.y()-radius*.5f,center.z()-radius*.5f);

    osgText::Text* text1 = new osgText::Text;
    text1->setFont(new osgText::Font(new osgQt::QFontImplementation(QFont("Times"))));
    text1->setCharacterSize(characterSize);
    text1->setPosition(pos);
    text1->setAxisAlignment(osgText::Text::XY_PLANE);
    text1->setText("XY_PLANE");
    geode->addDrawable(text1);

    osgText::Text* text2 = new osgText::Text;
    text2->setFont(new osgText::Font(new osgQt::QFontImplementation(QFont("Times"))));
    text2->setCharacterSize(characterSize);
    text2->setPosition(pos);
    text2->setAxisAlignment(osgText::Text::YZ_PLANE);
    text2->setText("YZ_PLANE");
    geode->addDrawable(text2);

    osgText::Text* text3 = new osgText::Text;
    text3->setFont(new osgText::Font(new osgQt::QFontImplementation(QFont("Times"))));
    text3->setCharacterSize(characterSize);
    text3->setPosition(pos);
    text3->setAxisAlignment(osgText::Text::XZ_PLANE);
    text3->setText("XZ_PLANE");
    geode->addDrawable(text3);


    osgText::Text* text4 = new osgText::Text;
    text4->setFont(new osgText::Font(new osgQt::QFontImplementation(QFont("Times"))));
    text4->setCharacterSize(characterSize);
    text4->setPosition(center);
    text4->setAxisAlignment(osgText::Text::SCREEN);

    osg::Vec4 characterSizeModeColor(1.0f,0.0f,0.5f,1.0f);

    osgText::Text* text5 = new osgText::Text;
    text5->setColor(characterSizeModeColor);
    text5->setFont(new osgText::Font(new osgQt::QFontImplementation(QFont("Times"))));
    //text5->setCharacterSize(characterSize);
    text5->setCharacterSize(32.0f); // medium
    text5->setPosition(center - osg::Vec3(0.0, 0.0, 0.2));
    text5->setAxisAlignment(osgText::Text::SCREEN);
    text5->setCharacterSizeMode(osgText::Text::SCREEN_COORDS);
    text5->setText("CharacterSizeMode SCREEN_COORDS(size 32.0)");
    geode->addDrawable(text5);

    osgText::Text* text6 = new osgText::Text;
    text6->setColor(characterSizeModeColor);
    text6->setFont(new osgText::Font(new osgQt::QFontImplementation(QFont("Times"))));
    text6->setCharacterSize(characterSize);
    text6->setPosition(center - osg::Vec3(0.0, 0.0, 0.4));
    text6->setAxisAlignment(osgText::Text::SCREEN);
    text6->setCharacterSizeMode(osgText::Text::OBJECT_COORDS_WITH_MAXIMUM_SCREEN_SIZE_CAPPED_BY_FONT_HEIGHT);
    text6->setText("CharacterSizeMode OBJECT_COORDS_WITH_MAXIMUM_SCREEN_SIZE_CAPPED_BY_FONT_HEIGHT");
    geode->addDrawable(text6);

    osgText::Text* text7 = new osgText::Text;
    text7->setColor(characterSizeModeColor);
    text7->setFont(new osgText::Font(new osgQt::QFontImplementation(QFont("Times"))));
    text7->setCharacterSize(characterSize);
    text7->setPosition(center - osg::Vec3(0.0, 0.0, 0.6));
    text7->setAxisAlignment(osgText::Text::SCREEN);
    text7->setCharacterSizeMode(osgText::Text::OBJECT_COORDS);
    text7->setText("CharacterSizeMode OBJECT_COORDS (default)");
    geode->addDrawable(text7);

#if 1
    // reproduce outline bounding box compute problem with backdrop on.
    text4->setBackdropType(osgText::Text::OUTLINE);
    text4->setDrawMode(osgText::Text::TEXT | osgText::Text::BOUNDINGBOX);
#endif

    text4->setText("SCREEN");
    geode->addDrawable(text4);

    osg::ShapeDrawable* shape = new osg::ShapeDrawable(new osg::Sphere(center,characterSize*0.2f));
    shape->getOrCreateStateSet()->setMode(GL_LIGHTING,osg::StateAttribute::ON);
    geode->addDrawable(shape);

    osg::Group* rootNode = new osg::Group;
    rootNode->addChild(geode);

    return rootNode;    
}

class MainWindow : public QWidget {
public:
    MainWindow()
    {
        osg::ref_ptr<osg::GraphicsContext::Traits> traits = new osg::GraphicsContext::Traits(osg::DisplaySettings::instance().get());
        traits->width = width();
        traits->height = height();
        traits->doubleBuffer = true;
        osgQt::GraphicsWindowQt* graphicsWindow = new osgQt::GraphicsWindowQt(traits.get());

        QGridLayout* grid = new QGridLayout;
        grid->setMargin(0);
        grid->addWidget(graphicsWindow->getGLWidget(), 0, 0);
        setLayout(grid);

        _viewer.setThreadingModel(osgViewer::Viewer::SingleThreaded);

        osg::Camera* camera = _viewer.getCamera();
        camera->setGraphicsContext(graphicsWindow);
        camera->setViewport(new osg::Viewport(0, 0, width(), height()));

        startTimer(10);
    }

    virtual void paintEvent(QPaintEvent* event)
    {
        _viewer.frame();
    }
    virtual void timerEvent(QTimerEvent* event)
    {
        _viewer.frame();
    }

    void setSceneData(osg::Node* node)
    {
        _viewer.setSceneData(node);
    }
    void setCameraManipulator(osgGA::CameraManipulator* manipulator, bool resetPosition = true)
    {
        _viewer.setCameraManipulator(manipulator, resetPosition);
    }

private:
    osgViewer::Viewer _viewer;
};

int main(int argc, char** argv)
{
    QApplication app(argc, argv);

    // prepare scene.
    osg::Vec3 center(0.0f,0.0f,0.0f);
    float radius = 1.0f;
    
    // create the hud.
    osg::ref_ptr<osg::Camera> camera = new osg::Camera;
    camera->setReferenceFrame(osg::Transform::ABSOLUTE_RF);
    camera->setProjectionMatrixAsOrtho2D(0,1280,0,1024);
    camera->setViewMatrix(osg::Matrix::identity());
    camera->setClearMask(GL_DEPTH_BUFFER_BIT);
    camera->addChild(createHUDText());
    camera->getOrCreateStateSet()->setMode(GL_LIGHTING,osg::StateAttribute::OFF);
    
    // make sure the root node is group so we can add extra nodes to it.
    osg::ref_ptr<osg::Group> group = new osg::Group;
    group->addChild(camera.get());
    group->addChild(create3DText(center, radius));

    // The qt window
    MainWindow widget;
    
    // set the scene to render
    widget.setSceneData(group.get());
    widget.setCameraManipulator(new osgGA::TrackballManipulator);

    widget.setGeometry(100, 100, 800, 600);
    widget.show();

    return app.exec();
}