protected override void UpdateContainedPairs()
{
//Could go other way; get triangles in mesh that overlap the compound.
//Could be faster sometimes depending on the way it's set up.
var overlappedElements = PhysicsResources.GetCompoundChildList();
compoundInfo.hierarchy.Tree.GetOverlaps(terrain.boundingBox, overlappedElements);
for (int i = 0; i < overlappedElements.Count; i++)
{
TryToAdd(overlappedElements.Elements[i].CollisionInformation, terrain, overlappedElements.Elements[i].Material, terrain.Material);
}
PhysicsResources.GiveBack(overlappedElements);
}