void VSA_Component::Init(int NbProxy)
{
////Creation of the initial proxies by random seed triangle picking
m_Table_Proxy.clear();
m_NbProxy=NbProxy;
int NbFacet=m_Poly->size_of_facets();
int offset=NbFacet/NbProxy;
int i=0;
for(Facet_iterator pface = m_Poly->facets_begin();
pface != m_Poly->facets_end();
pface++)
{
if(i%offset==0)///this triangle is chosen
{
//a proxy is created
Proxy NewProxy;
NewProxy.Normal=pface->normal();
NewProxy.Seed=pface;
///the proxy is added
m_Table_Proxy.push_back(NewProxy);
}
pface->LabelVSA=-1;
i++;
}
m_Poly->NbFaceLabel=m_NbProxy;
}
double VSA_Component::DistorsionError(Facet_iterator f,Proxy p)
{
Vector v=f->normal()-p.Normal;
double nrm=v*v;
double area=AreaFacetTriangleSeg(f);
return nrm*area;
}
void VSA_Component::ProxyFitting()
{
Vector * TabNormal=new Vector[m_NbProxy];
double * TabArea=new double[m_NbProxy];
double * DistanceMin=new double[m_NbProxy];
double * DistanceMax=new double[m_NbProxy];
for (int i=0;i<m_NbProxy;i++)
{
TabArea[i]=0;
TabNormal[i]=CGAL::NULL_VECTOR;
DistanceMin[i]=100000000;
DistanceMax[i]=0;
}
for(Facet_iterator pface = m_Poly->facets_begin();
pface != m_Poly->facets_end();
pface++)
{
double area=AreaFacetTriangleSeg(pface);
TabArea[pface->LabelVSA]+=area;
TabNormal[pface->LabelVSA]=TabNormal[pface->LabelVSA]+pface->normal()*area;
}
for (int i=0;i<m_NbProxy;i++)
{
m_Table_Proxy[i].Normal=TabNormal[i]/TabArea[i];
m_Table_Proxy[i].Area=TabArea[i];
m_Table_Proxy[i].TotalDistorsion=0;
}
// a new seed is assigned to each proxy
for(Facet_iterator pface = m_Poly->facets_begin();
pface != m_Poly->facets_end();
pface++)
{
double distance=DistorsionError(pface,m_Table_Proxy[pface->LabelVSA]);
m_Table_Proxy[pface->LabelVSA].TotalDistorsion+=distance;
if(distance<DistanceMin[pface->LabelVSA])
{
DistanceMin[pface->LabelVSA]=distance;
m_Table_Proxy[pface->LabelVSA].Seed=pface;
}
//we pick the facet corresponding to the max distorsion
if(distance>DistanceMax[pface->LabelVSA])
{
DistanceMax[pface->LabelVSA]=distance;
m_Table_Proxy[pface->LabelVSA].MostDistordedFacet=pface;
}
}
delete []DistanceMin;
delete []TabNormal;
delete []TabArea;
delete []DistanceMax;
}