Delete and insert operations in Delaunay mesh

Adopt algorith in respect to : [login to view URL] - only Delaunay is of my concern Keep in mind that only local modification is objective to this project, i don't need algo that incrementally calculates Delaunay and then substracts - it is very important - speed is the factor !!!! Given: $points[point_id] = [1,1] - point represntation where point_id = index = int; [1,1] - coords x,y x,y = int $dmesh[] = [[1,2,3], [4,5,6], ... ] array of triangles( Delaunay triangulation) each point is represented by point_id algo starts with 4 points constructing bounding box: point[0] = [0,0]; point[1] = [0,max_int];point[2] = [max_int,max_int];point[3] = [max_int,0]; $dmesh = [[0,1,2], [0,2,3]]; Objectives: 1. function insert_into_dmesh(point_id) { .... code that modifies dmesh to meet Delaunay triangulation with new point ... return : [array of triangles that where removed, array of triangles that where inserted] } 2. function remove_from_dmesh(point_id) { .... code that modifies dmesh to meet Delaunay triangulation without new point ... return : [array of triangles that where removed, array of triangles that where inserted] }