// compute FWN cache for all points underneath this box
protected void make_box_fast_winding_cache(int iBox, IEnumerable <int> pointIndices)
{
Util.gDevAssert(FastWindingCache.ContainsKey(iBox) == false);
// construct cache
var cacheInfo = new FWNInfo();
FastPointWinding.ComputeCoeffs(points, pointIndices, FastWindingAreaCache,
ref cacheInfo.Center, ref cacheInfo.R, ref cacheInfo.Order1Vec, ref cacheInfo.Order2Mat);
FastWindingCache[iBox] = cacheInfo;
}
// evaluate the FWN cache for iBox
protected double evaluate_box_fast_winding_cache(int iBox, ref Vector3d q)
{
FWNInfo cacheInfo = FastWindingCache[iBox];
if (FWNApproxOrder == 2)
{
return(FastPointWinding.EvaluateOrder2Approx(ref cacheInfo.Center, ref cacheInfo.Order1Vec, ref cacheInfo.Order2Mat, ref q));
}
else
{
return(FastPointWinding.EvaluateOrder1Approx(ref cacheInfo.Center, ref cacheInfo.Order1Vec, ref q));
}
}
// evaluate winding number contribution for all points below iBox
protected double branch_fast_winding_num(int iBox, Vector3d p)
{
double branch_sum = 0;
int idx = box_to_index[iBox];
if (idx < points_end)
{ // point-list case, array is [N t1 t2 ... tN]
int num_pts = index_list[idx];
for (int i = 1; i <= num_pts; ++i)
{
int pi = index_list[idx + i];
Vector3d v = Points.GetVertex(pi);
Vector3d n = Points.GetVertexNormal(pi);
double a = FastWindingAreaCache[pi];
branch_sum += FastPointWinding.ExactEval(ref v, ref n, a, ref p);
}
}
else
{ // internal node, either 1 or 2 child boxes
int iChild1 = index_list[idx];
if (iChild1 < 0)
{ // 1 child, descend if nearer than cur min-dist
iChild1 = (-iChild1) - 1;
// if we have winding cache, we can more efficiently compute contribution of all points
// below this box. Otherwise, recursively descend tree.
bool contained = box_contains(iChild1, p);
if (contained == false && can_use_fast_winding_cache(iChild1, ref p))
{
branch_sum += evaluate_box_fast_winding_cache(iChild1, ref p);
}
else
{
branch_sum += branch_fast_winding_num(iChild1, p);
}
}
else
{ // 2 children, descend closest first
iChild1 = iChild1 - 1;
int iChild2 = index_list[idx + 1] - 1;
bool contained1 = box_contains(iChild1, p);
if (contained1 == false && can_use_fast_winding_cache(iChild1, ref p))
{
branch_sum += evaluate_box_fast_winding_cache(iChild1, ref p);
}
else
{
branch_sum += branch_fast_winding_num(iChild1, p);
}
bool contained2 = box_contains(iChild2, p);
if (contained2 == false && can_use_fast_winding_cache(iChild2, ref p))
{
branch_sum += evaluate_box_fast_winding_cache(iChild2, ref p);
}
else
{
branch_sum += branch_fast_winding_num(iChild2, p);
}
}
}
return(branch_sum);
}
