OpenSceneGraph/examples/osgbillboard/osgbillboard.cpp

#include <osg/Node>
#include <osg/Geometry>
#include <osg/Notify>
#include <osg/MatrixTransform>
#include <osg/Texture2D>
#include <osg/Billboard>
#include <osg/LineWidth>

#include <osgGA/TrackballManipulator>
#include <osgGA/FlightManipulator>
#include <osgGA/DriveManipulator>

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

#include <osgViewer/Viewer>

//
// A simple demo demonstrating different texturing modes, 
// including using of texture extensions.
//


typedef std::vector< osg::ref_ptr<osg::Image> > ImageList;

/** create quad at specified position. */
osg::Drawable* createSquare(const osg::Vec3& corner,const osg::Vec3& width,const osg::Vec3& height, osg::Image* image=NULL)
{
    // set up the Geometry.
    osg::Geometry* geom = new osg::Geometry;

    osg::Vec3Array* coords = new osg::Vec3Array(4);
    (*coords)[0] = corner;
    (*coords)[1] = corner+width;
    (*coords)[2] = corner+width+height;
    (*coords)[3] = corner+height;


    geom->setVertexArray(coords);

    osg::Vec3Array* norms = new osg::Vec3Array(1);
    (*norms)[0] = width^height;
    (*norms)[0].normalize();
    
    geom->setNormalArray(norms);
    geom->setNormalBinding(osg::Geometry::BIND_OVERALL);

    osg::Vec2Array* tcoords = new osg::Vec2Array(4);
    (*tcoords)[0].set(0.0f,0.0f);
    (*tcoords)[1].set(1.0f,0.0f);
    (*tcoords)[2].set(1.0f,1.0f);
    (*tcoords)[3].set(0.0f,1.0f);
    geom->setTexCoordArray(0,tcoords);
    
    geom->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::QUADS,0,4));
    
    if (image)
    {
        osg::StateSet* stateset = new osg::StateSet;
        osg::Texture2D* texture = new osg::Texture2D;
        texture->setImage(image);
        stateset->setTextureAttributeAndModes(0,texture,osg::StateAttribute::ON);
        geom->setStateSet(stateset);
    }
    
    return geom;
}

osg::Drawable* createAxis(const osg::Vec3& corner,const osg::Vec3& xdir,const osg::Vec3& ydir,const osg::Vec3& zdir)
{
    // set up the Geometry.
    osg::Geometry* geom = new osg::Geometry;

    osg::Vec3Array* coords = new osg::Vec3Array(6);
    (*coords)[0] = corner;
    (*coords)[1] = corner+xdir;
    (*coords)[2] = corner;
    (*coords)[3] = corner+ydir;
    (*coords)[4] = corner;
    (*coords)[5] = corner+zdir;

    geom->setVertexArray(coords);

    osg::Vec4 x_color(0.0f,1.0f,1.0f,1.0f);
    osg::Vec4 y_color(0.0f,1.0f,1.0f,1.0f);
    osg::Vec4 z_color(1.0f,0.0f,0.0f,1.0f);

    osg::Vec4Array* color = new osg::Vec4Array(6);
    (*color)[0] = x_color;
    (*color)[1] = x_color;
    (*color)[2] = y_color;
    (*color)[3] = y_color;
    (*color)[4] = z_color;
    (*color)[5] = z_color;
    
    geom->setColorArray(color);
    geom->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
    
    geom->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::LINES,0,6));
    
    osg::StateSet* stateset = new osg::StateSet;
    osg::LineWidth* linewidth = new osg::LineWidth();
    linewidth->setWidth(4.0f);
    stateset->setAttributeAndModes(linewidth,osg::StateAttribute::ON);
    stateset->setMode(GL_LIGHTING,osg::StateAttribute::OFF);
    geom->setStateSet(stateset);
    
    return geom;
}

osg::Node* createModel()
{

    // create the root node which will hold the model.
    osg::Group* root = new osg::Group();

    // add the drawable into a single goede to be shared...
    osg::Billboard* center = new osg::Billboard();
    center->setMode(osg::Billboard::POINT_ROT_EYE);
    center->addDrawable(
        createSquare(osg::Vec3(-0.5f,0.0f,-0.5f),osg::Vec3(1.0f,0.0f,0.0f),osg::Vec3(0.0f,0.0f,1.0f),osgDB::readImageFile("Images/reflect.rgb")),
        osg::Vec3(0.0f,0.0f,0.0f));
        
    osg::Billboard* x_arrow = new osg::Billboard();
    x_arrow->setMode(osg::Billboard::AXIAL_ROT);
    x_arrow->setAxis(osg::Vec3(1.0f,0.0f,0.0f));
    x_arrow->setNormal(osg::Vec3(0.0f,-1.0f,0.0f));
    x_arrow->addDrawable(
       createSquare(osg::Vec3(-0.5f,0.0f,-0.5f),osg::Vec3(1.0f,0.0f,0.0f),osg::Vec3(0.0f,0.0f,1.0f),osgDB::readImageFile("Cubemap_axis/posx.png")),
       osg::Vec3(5.0f,0.0f,0.0f));

    osg::Billboard* y_arrow = new osg::Billboard();
    y_arrow->setMode(osg::Billboard::AXIAL_ROT);
    y_arrow->setAxis(osg::Vec3(0.0f,1.0f,0.0f));
    y_arrow->setNormal(osg::Vec3(1.0f,0.0f,0.0f));
    y_arrow->addDrawable(
        createSquare(osg::Vec3(0.0f,-0.5f,-0.5f),osg::Vec3(0.0f,1.0f,0.0f),osg::Vec3(0.0f,0.0f,1.0f),osgDB::readImageFile("Cubemap_axis/posy.png")),
        osg::Vec3(0.0f,5.0f,0.0f));

    osg::Billboard* z_arrow = new osg::Billboard();
    z_arrow->setMode(osg::Billboard::AXIAL_ROT);
    z_arrow->setAxis(osg::Vec3(0.0f,0.0f,1.0f));
    z_arrow->setNormal(osg::Vec3(0.0f,-1.0f,0.0f));
    z_arrow->addDrawable(
        createSquare(osg::Vec3(-0.5f,0.0f,-0.5f),osg::Vec3(1.0f,0.0f,0.0f),osg::Vec3(0.0f,0.0f,1.0f),osgDB::readImageFile("Cubemap_axis/posz.png")),
        osg::Vec3(0.0f,0.0f,5.0f));



    osg::Geode* axis = new osg::Geode();
    axis->addDrawable(createAxis(osg::Vec3(0.0f,0.0f,0.0f),osg::Vec3(5.0f,0.0f,0.0f),osg::Vec3(0.0f,5.0f,0.0f),osg::Vec3(0.0f,0.0f,5.0f)));


    root->addChild(center);
    root->addChild(x_arrow);
    root->addChild(y_arrow);
    root->addChild(z_arrow);
    root->addChild(axis);

    return root;
}

int main(int, char**)
{
    // construct the viewer
    osgViewer::Viewer viewer;
    
    // set the scene to render
    viewer.setSceneData(createModel());

    // run the viewers frame loop
    return viewer.run();
}