collapse static method

void collapse(List<Vertex> vertices, List<Tri> faces, Vertex u, Vertex? v,)

Implementation

static void collapse(List<Vertex> vertices,List<Tri> faces, Vertex u, Vertex? v){ // u and v are pointers to vertices of an edge
  // Collapse the edge uv by moving vertex u onto v
  if (v == null) {
    // u is a vertex all by itself so just delete it..
    removeVertex( u, vertices );
    return;
  }

  final tmpVertices = [];

  for (int i = 0; i < u.neighbors.length; i ++ ) {
    tmpVertices.add( u.neighbors[ i ] );
  }


  // delete triangles on edge uv:
  for (int i = u.faces.length - 1; i >= 0; i -- ) {
    if(u.faces[i] != null && u.faces[ i ]!.hasVertex( v ) ) {
      removeFace( u.faces[ i ]!, faces );
    }
  }

  // update remaining triangles to have v instead of u
  for (int i = u.faces.length - 1; i >= 0; i -- ) {
    if(u.faces[i] != null){
      u.faces[i]!.replaceVertex(u, v);
    }
  }


  removeVertex( u, vertices );

  // recompute the edge collapse costs in neighborhood
  for (int i = 0; i < tmpVertices.length; i ++ ) {
    computeEdgeCostAtVertex( tmpVertices[ i ] );
  }
}