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[Nguyen Tan Khoa <>]

Dear Koutsokeras Miltiadis,

You can apply a bread-first search algorithm to find the N-rings. You can take a look at this snippet of code:

HV_circulator circulator;

QList<VERTEXHANDLEWITHLEVEL> toGrow;

QList<int> exploredVertices, exploredVertices1;

VERTEXHANDLEWITHLEVEL currentVH;

std::vector<Point> result;

// initialization

exploredVertices.clear();

exploredVertices1.clear();

result.clear();

currentVH.vh = v;

currentVH.level = 1;

toGrow.push_back( currentVH );

//std::cout << "Incident vertices of " << v->index << " are: ";

while ( !toGrow.isEmpty() ) {

currentVH = toGrow.takeFirst();

circulator = currentVH.vh->vertex_begin();

exploredVertices.push_front( currentVH.vh->index );

if ( currentVH.level > linkSize ) {

break;

} else {

do {

if ( exploredVertices.indexOf( circulator->next()->vertex()->index ) == -1 ) {

toGrow.push_back( VERTEXHANDLEWITHLEVEL(circulator->next()->vertex(), currentVH.level+1) );

if ( currentVH.level + 1 > linkSize ) {

result.push_back( circulator->next()->vertex()->point() );

//std::cout << circulator->next()->vertex()->index << "\t";

// std::cout << result[result.size()-1] << std::endl;

}

exploredVertices.push_back( circulator->next()->vertex()->index );

}

} while (++circulator != currentVH.vh->vertex_begin());

//std::cout << std::endl;

}

}

return result;

On Apr 3, 2007, at 11:07 PM, Koutsokeras Miltiadis wrote:

Can someone point out how to robustly compute N-ring neighbors of vertices and faces of Polyhedral surfaces? Circulators provide the 1-ring neighbors but I haven't found any examples about N-rings. Thank you in advance for every reply.

-- 

Koutsokeras Miltiadis

Computational Intelligence Laboratory (http://www.iit.demokritos.gr/cil/)

Institute of Informatics and Telecommunications

National Center for Scientific Research "Demokritos"

P.O. BOX   60228

GR-153 10 Agia Paraskevi, Athens, Greece.

-- 

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