Такс...создал я квад
mesh = CreateMesh()
surf = CreateSurface(mesh)
v0 = AddVertex (surf, -5,-5,0, 0 ,0)
v1 = AddVertex (surf, 5,-5,0, 1 ,0)
v2 = AddVertex (surf, -5, 5,0, 0.5,1)
t0 = AddVertex (surf, 5,-5,0, 0 ,0)
t1 = AddVertex (surf, 5,5,0, 1 ,0)
t2 = AddVertex (surf, -5, 5,0, 0.5,1)
tri = AddTriangle (surf,v0,v2,v1)
tri2 = AddTriangle (surf,t0,t2,t1)
Пикать его
PickedSurface или
PickedEntity?