private static void AddObject(SSBVHNodeAdaptor <GO> nAda, ssBVHNode <GO> curNode, GO newOb, ref Bounds_d newObBox, double newObSAH)
{
// 1. first we traverse the node looking for the best leaf
while (curNode.ContainedObjects == null)
{
// find the best way to add this object.. 3 options..
// 1. send to left node (L+N,R)
// 2. send to right node (L,R+N)
// 3. merge and pushdown left-and-right node (L+R,N)
var left = curNode.Left;
var right = curNode.Right;
double leftSAH = SA(left);
double rightSAH = SA(right);
double sendLeftSAH = rightSAH + SA(left.Bounds.ExpandedToFit(newObBox)); // (L+N,R)
double sendRightSAH = leftSAH + SA(right.Bounds.ExpandedToFit(newObBox)); // (L,R+N)
double mergedLeftAndRightSAH = SA(BoundsOfPair(left, right)) + newObSAH; // (L+R,N)
// Doing a merge-and-pushdown can be expensive, so we only do it if it's notably better
const double MERGE_DISCOUNT = 0.3f;
if (mergedLeftAndRightSAH < (Math.Min(sendLeftSAH, sendRightSAH)) * MERGE_DISCOUNT)
{
addObject_Pushdown(nAda, curNode, newOb);
return;
}
if (sendLeftSAH < sendRightSAH)
{
curNode = left;
}
else
{
curNode = right;
}
}
// 2. then we add the object and map it to our leaf
curNode.ContainedObjects.Add(newOb);
nAda.MapObjectToBvhLeaf(newOb, curNode);
curNode.RefitVolume(nAda);
// split if necessary...
curNode.SplitIfNecessary(nAda);
}
