NodeSet ProjectOntoLevset(int jCell, NodeSet Nodes)
{
int D = Nodes.GetLength(1);
int NoOfNodes = Nodes.GetLength(0);
var m_Context = this.tracker.GridDat;
LevelSet LevSet = (LevelSet)(this.tracker.LevelSets[this.LevelSetIndex]);
MultidimensionalArray LevSetValues = MultidimensionalArray.Create(1, NoOfNodes);
MultidimensionalArray LevSetGrad = MultidimensionalArray.Create(1, NoOfNodes, D);
MultidimensionalArray x0_i_Local = MultidimensionalArray.Create(1, NoOfNodes, D);
MultidimensionalArray x0_i_Global = MultidimensionalArray.Create(1, NoOfNodes, D); // quadrature nodes in global coordinates
MultidimensionalArray x0_ip1_Local = MultidimensionalArray.Create(1, NoOfNodes, D);
MultidimensionalArray x0_ip1_Global = MultidimensionalArray.Create(NoOfNodes, D);
// set initial value;
x0_i_Local.SetSubArray(Nodes, 0, -1, -1);
int NN = NoOfNodes;
for (int i = 0; i < 10; i++)
{
double radiusError = 0;
int j = jCell;
LevSet.Evaluate(j, 1, Nodes, LevSetValues, 0, 0.0);
LevSet.EvaluateGradient(j, 1, Nodes, LevSetGrad);
m_Context.TransformLocal2Global(new NodeSet(this.Kref, x0_i_Local.ExtractSubArrayShallow(0, -1, -1)), j, 1, x0_i_Global, 0);
for (int nn = 0; nn < NN; nn++)
{
double sc = 0;
for (int d = 0; d < D; d++)
{
sc += LevSetGrad[0, nn, d].Pow2();
}
for (int d = 0; d < D; d++)
{
double xd = x0_i_Global[0, nn, d] - LevSetGrad[0, nn, d] * LevSetValues[0, nn] / sc;
x0_ip1_Global[nn, d] = xd;
}
radiusError += Math.Abs(LevSetValues[0, nn]);
}
m_Context.TransformGlobal2Local(x0_ip1_Global, x0_ip1_Local, j, 1, 0);
// next iter: x0_i <- x0_{i+1}
x0_i_Local.Set(x0_ip1_Local);
Nodes = (new NodeSet(this.Kref, x0_i_Local.ExtractSubArrayShallow(0, -1, -1)));
}
return(Nodes);
}