Hi,
I'm using the DepthPartitionNode code from the osgdepthpartition
example, OSG v2.6, to display complex scenes composed by many planets
and their relative orbits, that here for simplicity you can consider
as circles centered on the Sun. DPN does not seem to play well with
orbits. To reproduce the problem, I've attached a modified version of
osgdepthpartition.cpp that simply adds the Earth orbit to the original
scene. Just copy it on the original one and it should compile.
When you move the camera around, you will see that the orbit is not
displayed completely, especially the part on the opposite side of the
Sun. Also, arcs of the orbit seem to disappear and suddenly reappear
when moving slightly the camera, with no apparent reason. I would be
glad to hear if you can reproduce this issue, and help me find a way
around it.
Regards,
Pasquale
/* OpenSceneGraph example, osgdepthpartion.
*
* 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 <osgUtil/UpdateVisitor>
#include <osgDB/ReadFile>
#include <osg/ShapeDrawable>
#include <osg/PositionAttitudeTransform>
#include <osgGA/TrackballManipulator>
#include <osgViewer/Viewer>
#include "DepthPartitionNode.h"
const double r_earth = 6378.137;
const double r_sun = 695990.0;
const double AU = 149697900.0;
osg::Node* createScene()
{
// Create the Earth, in blue
osg::ShapeDrawable *earth_sd = new osg::ShapeDrawable;
osg::Sphere* earth_sphere = new osg::Sphere;
earth_sphere->setRadius(r_earth);
earth_sd->setShape(earth_sphere);
earth_sd->setColor(osg::Vec4(0, 0, 1.0, 1.0));
osg::Geode* earth = new osg::Geode;
earth->setName("earth");
earth->addDrawable(earth_sd);
// Create the Sun, in yellow
osg::ShapeDrawable *sun_sd = new osg::ShapeDrawable;
osg::Sphere* sun_sphere = new osg::Sphere;
sun_sphere->setRadius(r_sun);
sun_sd->setShape(sun_sphere);
sun_sd->setColor(osg::Vec4(1.0, 0.0, 0.0, 1.0));
osg::Geode* sun_geode = new osg::Geode;
sun_geode->setName("sun");
sun_geode->addDrawable(sun_sd);
// Move the sun behind the earth
osg::PositionAttitudeTransform *pat = new osg::PositionAttitudeTransform;
pat->setPosition(osg::Vec3d(0.0, AU, 0.0));
osg::Geometry * unitCircle = new osg::Geometry();
{
osg::Vec4Array * colours = new osg::Vec4Array(1);
(*colours)[0] = osg::Vec4d(1.0,1.0,1.0,1.0);
unitCircle->setColorArray(colours);
unitCircle->setColorBinding(osg::Geometry::BIND_OVERALL);
const unsigned int n_points = 1024;
osg::Vec3Array * coords = new osg::Vec3Array(n_points);
const double dx = 6.28/n_points;
double s,c;
for (unsigned int j=0; j<n_points; ++j) {
sincos(dx*j,&s,&c);
(*coords)[j].set(osg::Vec3d(c,s,0.0));
}
unitCircle->setVertexArray(coords);
unitCircle->getOrCreateStateSet()->setMode(GL_LIGHTING,osg::StateAttribute::OFF);
unitCircle->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::LINE_LOOP,0,n_points));
}
// Earth orbit
osg::Geode * earthOrbit = new osg::Geode;
earthOrbit->addDrawable(unitCircle);
osg::PositionAttitudeTransform * earthOrbitPAT = new osg::PositionAttitudeTransform;
earthOrbitPAT->setScale(osg::Vec3d(AU,AU,AU));
earthOrbitPAT->setPosition(osg::Vec3d(0.0, AU, 0.0));
earthOrbitPAT->addChild(earthOrbit);
osg::Group* scene = new osg::Group;
scene->addChild(earth);
scene->addChild(pat);
scene->addChild(earthOrbitPAT);
pat->addChild(sun_geode);
return scene;
}
int main( int argc, char **argv )
{
// use an ArgumentParser object to manage the program arguments.
osg::ArgumentParser arguments(&argc,argv);
// construct the viewer.
osgViewer::Viewer viewer;
bool needToSetHomePosition = false;
// read the scene from the list of file specified commandline args.
osg::ref_ptr<osg::Node> scene = osgDB::readNodeFiles(arguments);
// if one hasn't been loaded create an earth and sun test model.
if (!scene)
{
scene = createScene();
needToSetHomePosition = true;
}
// Create a DepthPartitionNode to manage partitioning of the scene
osg::ref_ptr<DepthPartitionNode> dpn = new DepthPartitionNode;
dpn->addChild(scene.get());
dpn->setActive(true); // Control whether the node analyzes the scene
// pass the loaded scene graph to the viewer.
viewer.setSceneData(dpn.get());
viewer.setCameraManipulator(new osgGA::TrackballManipulator);
if (needToSetHomePosition)
{
viewer.getCameraManipulator()->setHomePosition(osg::Vec3d(0.0,-5.0*r_earth,0.0),osg::Vec3d(0.0,0.0,0.0),osg::Vec3d(0.0,0.0,1.0));
}
// depth partion node is only supports single window/single threaded at present.
viewer.setThreadingModel(osgViewer::Viewer::SingleThreaded);
return viewer.run();
}
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