Johannes, If you just want to triangulate an outline, try the osgUtil::Tessellator. First build an osg::Geometry as a line loop, then do something like:
osgUtil::Tessellator tess; tess.setTessellationType( osgUtil::Tessellator::TESS_TYPE_GEOMETRY ); tess.setWindingType( osgUtil::Tessellator::TESS_WINDING_POSITIVE ); tess.retessellatePolygons( *geometry ); Glenn Waldron : Pelican Mapping : http://pelicanmapping.com : +1.703.652.4791 On Tue, Sep 1, 2009 at 2:30 PM, Johannes Schüth<[email protected]> wrote: > Hi, > > i want to triangulate the following U character like shape. > [Image: http://jotschi.de/download/osg/delaunay_3.png ] > > The DelaunayTriangulator generates this triangulated mesh. But as you can see > the space in the middle of the U is also triangulated which i do not want. > [Image: http://jotschi.de/download/osg/delaunay_2.png ] > > So i tried the DelaunayConstraint to add a constraint for all edges. > Obviously i have no clue how to do this but i attach the image anyway. This > doesn't seem to work: > [Image: http://jotschi.de/download/osg/delaunay_1.png ] > > I used the following code: > > Code: > > osg::Group* root = new osg::Group(); > > osg::Vec3Array* v = new osg::Vec3Array; > v->resize(16); > > //U > (*v)[0].set(500, 250, 0); > (*v)[1].set(500, 1000, 0); > > (*v)[2].set(500, 1000, 0); > (*v)[3].set(1300, 1000, 0); > > (*v)[4].set(1300, 1000, 0); > (*v)[5].set(1300, 250, 0); > > (*v)[6].set(1300, 250, 0); > (*v)[7].set(1200, 250, 0); > > (*v)[8].set(1200, 250, 0); > (*v)[9].set(1200, 900, 0); > > (*v)[10].set(1200, 900, 0); > (*v)[11].set(650, 900, 0); > > (*v)[12].set(650, 900, 0); > (*v)[13].set(650, 200, 0); > > (*v)[14].set(650, 200, 0); > (*v)[15].set(500, 250, 0); > > > > osg::ref_ptr<osgUtil::DelaunayTriangulator> trig = > new osgUtil::DelaunayTriangulator(); > trig->setInputPointArray(v); > > > > osg::ref_ptr<osgUtil::DelaunayConstraint> constraint = > new osgUtil::DelaunayConstraint; > > constraint->setVertexArray(v); > constraint->addPrimitiveSet(new osg::DrawArrays( > osg::PrimitiveSet::LINE_LOOP, 0, 3)); > trig->addInputConstraint(constraint.get()); > > > trig->triangulate(); > trig->removeInternalTriangles(constraint.get()); > > osg::Geometry* gm = new osg::Geometry; > gm->setVertexArray(v); > gm->addPrimitiveSet(trig->getTriangles()); > osg::Vec4Array* colors = new osg::Vec4Array(1); > colors->push_back(osg::Vec4(1, 0, 1, 1)); > gm->setColorArray(colors); > gm->setColorBinding(osg::Geometry::BIND_OVERALL); > osg::Geode* geode = new osg::Geode(); > geode->addDrawable(gm); > > // you do not need this function call to use this example > //forcedWireFrameModeOn(root); > > root->addChild(geode); > > /* > int nEdges = 16; > int i = 0; > while (i < nEdges) { > > osg::Vec4 c = osg::Vec4(1., 1., 1., 1.); > root->addChild(drawEdge(c, (*v)[i], (*v)[i + 1])); > > i += 2; > } > */ > > > > Do you have any idea how to solve this problem? I just want to get a > triangulated mesh from the imput of a shapes outline. (The input is not a > point cloud) > > Thank you! > > Cheers, > Johannes > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=16927#16927 > > > > > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
