OpenSceneGraph/src/osgPlugins/gles/WireframeVisitor

/* -*-c++-*- OpenSceneGraph - Copyright (C) Cedric Pinson
 *
 * This application is open source and may be redistributed and/or modified
 * freely and without restriction, both in commercial and non commercial
 * applications, as long as this copyright notice is maintained.
 *
 * This application is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
*/

#ifndef WIREFRAME_VISITOR
#define WIREFRAME_VISITOR

#include <set>

#include <osg/ValueObject>
#include <osg/Geode>
#include <osg/Geometry>

#include "GeometryUniqueVisitor"
#include "PrimitiveIndexors"


class WireframeVisitor : public GeometryUniqueVisitor
{
public:
    WireframeVisitor(bool inlined=false):
        GeometryUniqueVisitor("WireframeVisitor"),
        _inlined(inlined)
    {}

    void apply(osg::Node& node) {
        handleStateSet(node);
        traverse(node);
    }

    void apply(osg::Geode& geode) {
        handleStateSet(geode);
        for (unsigned int i = 0; i < geode.getNumDrawables(); i++) {
            apply(*geode.getDrawable(i));
        }
    }

    void apply(osg::Drawable& drawable) {
        osg::Geometry* geometry = drawable.asGeometry();
        if (!geometry) {
            return;
        }
        apply(*geometry);
    }

    void apply(osg::Geometry& geometry) {
        if(_processed.find(&geometry) == _processed.end()) {
            const unsigned int nbSourcePrimitives = geometry.getNumPrimitiveSets();
            for(unsigned int i = 0 ; i < nbSourcePrimitives ; ++ i) {
                osg::PrimitiveSet* primitive = geometry.getPrimitiveSet(i);
                EdgeIndexor edges;
                primitive->accept(edges);
                if(!edges._indices.empty()) {
                    osg::DrawElementsUInt* wireframe = new osg::DrawElementsUInt(osg::PrimitiveSet::LINES,
                                                                                 edges._indices.begin(),
                                                                                 edges._indices.end());
                    wireframe->setUserValue("wireframe", true);
                    geometry.getPrimitiveSetList().push_back(wireframe);
                }
            }

            _processed.insert(&geometry);
        }
    }

    void handleStateSet(osg::Node& node) {
        if(!_inlined) {
            node.setStateSet(0);
        }
    }

    std::set<osg::Geometry*> _processed;
    bool _inlined;
};

#endif