Area Subdivision and its assumptions

Question

Explain briefly the method of Area Subdivision and write down the short note on it assumptions?

Answer 1

This technique is essentially an image space method but employs object space operations re-ordering or sorting of surfaces according to depth. This technique takes merits of region coherence in a scene by positioning those view regions that represent the part of a single surface. In this technique, we successively subdivide the net viewing (screen) region, generally a rectangular window, into small rectangles till each small region is the projection of part of a single visible surface or no surface at all.

This technique has the following assumptions are as follows:

i) The plane of projection is z = 0 plane.

ii) The orthographic parallel projection.

iii) The direction of projection d = {0,0,-1)

iv) Suppose that the viewing (screen) region is a square.

v) Objects are builds up of polygon faces.