Area subdivision Method - Visible Surface Detection
What are the circumstances to be fulfilled, in Area-subdivision method, thus a surface not to be divided in addition?
Solution: In an area subdivision method, the known specified area IS not to be divided additionally, if the subsequent four conditions are satisfied as:
1) Surface should be outside the given area.
2) There should be one overlapping surface or one within surface.
3) One surrounding surface but not overlapping or no within surface.
4) A surrounding surface/obscures all other surfaces along with the given area.