source: experimental/distortionNG/distortionNG.cpp @ 309

#include "distortionNG.h"

#include<osg/Texture2D>
#include<osg/Point>
#include<osg/ComputeBoundsVisitor>

#include<osgViewer/Viewer>

#include<osgDB/ReadFile>

#include <osgUtil/SmoothingVisitor>



distortionNG::distortionNG()
{
}

distortionNG::~distortionNG()
{
}

osg::Geometry* distortionNG::createMesh( unsigned int column, unsigned int row )
{
        osg::ref_ptr<osg::Vec3Array> vertices = new osg::Vec3Array(column * row);
        osg::ref_ptr<osg::Vec2Array> texcoords = new osg::Vec2Array(column * row);
        for ( unsigned int i=0; i<row; ++i )
        {
                for ( unsigned int j=0; j<column; ++j )
                {
                        (*vertices)[i*column + j].set( (float)i, (float)j, 0.0f );
                        (*texcoords)[i*column + j].set( (float)i/(float)row, (float)j/(float)column );
                }
        }

        osg::ref_ptr<osg::Geometry> geom = new osg::Geometry;
        geom->setUseDisplayList( false );
        geom->setUseVertexBufferObjects( true );
        geom->setVertexArray( vertices.get() );
        geom->setTexCoordArray( 0, texcoords.get() );
        for ( unsigned int i=0; i<row-1; ++i )
        {
                osg::ref_ptr<osg::DrawElementsUInt> de = new osg::DrawElementsUInt(GL_QUAD_STRIP, column*2);
                for ( unsigned int j=0; j<column; ++j )
                {
                        (*de)[j*2 + 0] = i*column + j;
                        (*de)[j*2 + 1] = (i+1)*column + j;
                }
                geom->addPrimitiveSet( de.get() );
        }



        osg::ComputeBoundsVisitor cbv;
        cbv.applyDrawable(geom);
        osg::BoundingBox box = cbv.getBoundingBox();
        if (!box.valid()) 
                std::cout << "Invalid bounding box!"; 
        geom->setInitialBound(box);

        osg::ref_ptr<osg::Texture2D> texture = new osg::Texture2D;
        texture->setImage( osgDB::readImageFile("Images/osg256.png") );
        texture->setFilter( osg::Texture2D::MIN_FILTER, osg::Texture2D::LINEAR_MIPMAP_LINEAR );
        texture->setFilter( osg::Texture2D::MAG_FILTER, osg::Texture2D::LINEAR_MIPMAP_LINEAR );
        geom->getOrCreateStateSet()->setTextureAttributeAndModes( 0, texture.get() );

        // Create normals
        osgUtil::SmoothingVisitor::smooth( *geom );

        return geom.release();
}

osg::Geode* distortionHandler::createVertexHighlighter()
{
        osg::ref_ptr<osg::Vec4Array> colors = new osg::Vec4Array(1);
        (*colors)[0] = _highlightColor;

        _highlighter = new osg::Geometry;
        _highlighter->setDataVariance( osg::Object::DYNAMIC );
        _highlighter->setUseDisplayList( false );
        _highlighter->setUseVertexBufferObjects( true );
        _highlighter->setVertexArray( new osg::Vec3Array(1) );
        _highlighter->setColorArray( colors.get() );
        _highlighter->setColorBinding( osg::Geometry::BIND_OVERALL );
        _highlighter->addPrimitiveSet( new osg::DrawArrays(GL_POINTS, 0, 1) );

        osg::ref_ptr<osg::Geode> geode = new osg::Geode;
        geode->addDrawable( _highlighter.get() );
        geode->getOrCreateStateSet()->setAttributeAndModes( new osg::Point(10.0f) );
        geode->getOrCreateStateSet()->setMode( GL_LIGHTING, osg::StateAttribute::OFF );

        return geode.release();
}

bool distortionHandler::handle( const osgGA::GUIEventAdapter& ea, osgGA::GUIActionAdapter& aa )
{
    if ( ea.getEventType()!=osgGA::GUIEventAdapter::RELEASE ||
         ea.getButton()!=osgGA::GUIEventAdapter::LEFT_MOUSE_BUTTON ||
         !(ea.getModKeyMask()&osgGA::GUIEventAdapter::MODKEY_CTRL) )
        return false;
    
    osgViewer::View* viewer = dynamic_cast<osgViewer::View*>(&aa);
    if ( viewer )
    {
        osg::ref_ptr<osgUtil::LineSegmentIntersector> intersector = new osgUtil::LineSegmentIntersector(osgUtil::Intersector::WINDOW, ea.getX(), ea.getY());
        osgUtil::IntersectionVisitor iv( intersector.get() );
        viewer->getCamera()->accept( iv );
        
        if ( intersector->containsIntersections() )
        {
            osgUtil::LineSegmentIntersector::Intersection& result = *(intersector->getIntersections().begin());
            computeSelectedVertex( result );
        }
    }
    return false;
}

void distortionHandler::computeSelectedVertex( osgUtil::LineSegmentIntersector::Intersection& result )
{
        osg::Geometry* geom = dynamic_cast<osg::Geometry*>( result.drawable.get() );
        if ( !geom || !_highlighter || geom==_highlighter )
                return;

        osg::Vec3Array* vertices = dynamic_cast<osg::Vec3Array*>( geom->getVertexArray() );
        osg::Vec3Array* selVertices = dynamic_cast<osg::Vec3Array*>( _highlighter->getVertexArray() );
        if ( !vertices || !selVertices )
                return;

        osg::Vec3 point = result.getWorldIntersectPoint();
        osg::Matrix matrix = osg::computeLocalToWorld( result.nodePath );       // To compute the intersection vertices in world coordinates not in model coordinates
        //std::cout << "Intersection-indices: Size=" << result.indexList.size() << std::endl;
        const std::vector<unsigned int>& selIndices = result.indexList;
        {
                double maxRatio = 0.0;
                int closestVertexIndex = 0;
                for ( unsigned int i=0; i<3 && i<result.ratioList.size(); i++ ) //iterate through rations and search for max
                {
                        if(result.ratioList[i] > maxRatio)
                        {
                                maxRatio = result.ratioList[i];
                                closestVertexIndex = result.indexList[i];
                        }
                }
                osg::Vec3 vertex = (*vertices)[closestVertexIndex] * matrix;
                selVertices->front() = vertex;
        }

        selVertices->dirty();
        _highlighter->dirtyBound(); 
}