Hello,
I'm working on a project in which we need to output 3D objects
constructed by the code. We generate vertices and then triangles. When
the normal binding is per_primitive, every thing works fine. When it
is per_vertex, either the osgProducer::Viewer crashes or the result is
incorrect (badly shaded triangles). Here is the code:
if(geo->getNormalBinding() == osg::Geometry::BIND_PER_PRIMITIVE)
{
for(unsigned int i=0; i<maxFaceId; i++)
{
unsigned int A = GetFaceVertex(i, 0);
unsigned int B = GetFaceVertex(i, 1);
unsigned int C = GetFaceVertex(i, 2);
osg::Vec3f BA = vertices->at(A) - vertices->at(B);
osg::Vec3f CB = vertices->at(B) - vertices->at(C);
osg::Vec3f N = BA ^ CB;
N.normalize();
normals->push_back(N);
}
}
else if(geo->getNormalBinding() == osg::Geometry::BIND_PER_VERTEX)
{
for(unsigned int i=0; i<vertices->getNumElements(); i++)
normals->push_back(osg::Vec3f(0.0, 0.0, 0.0));
for(unsigned int i=0; i<maxFaceId; i++)
{
unsigned int A = GetFaceVertex(i, 0);
unsigned int B = GetFaceVertex(i, 1);
unsigned int C = GetFaceVertex(i, 2);
osg::Vec3f BA = vertices->at(A) - vertices->at(B);
osg::Vec3f CB = vertices->at(B) - vertices->at(C);
osg::Vec3f N = BA ^ CB;
(*normals)[A] += N;
(*normals)[B] += N;
(*normals)[C] += N;
}
for(unsigned int i=0; i<normals->getNumElements(); i++)
normals->at(i).normalize();
}
thanks
----------------------------------------------------------------
_______________________________________________
osg-users mailing list
[email protected]
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
