Visibility Detection of 3D Objects and Visual K-Nearest Neighbor Query Based on Convex Hull Model

Algorithm 5

kNN algorithm.

	Input: query point q, date set O, value k;
	Output: result set Visual;
(1)	BEGIN
(2)	ddl←Sort(O, q);
(3)	for each Obj in ddl do
(4)	qToObj←Add(q);
(5)	for each Obs in ddl do
(6)	if Obs.address < Obj.address then
(7)	TorF←GJK(qToObj, Obs);
(8)	end if
(9)	if (TorF = = true) then
(10)	ObsSet.Add(Obs);
(11)	end if
(12)	if ObsSet.Count = = 0 then
(13)	Visiual.Add(qToObj);
(14)	else
(15)	if(Occlusion(q, Obj, ObsSet)) then
(16)	Visiual.Add(Obj);
(17)	end if
(18)	end if
(19)	end for
(20)	end for
(21)	Return Visiual;
(22)	END