Hidden Surface Removal.

Copyright (c) Susan Laflin. August 1999.

References:Foley et al chapter 13, Rooney and Steadman chapter 14, Hearn and Baker chapter 13.

Interactive Computer Graphics. W.Giloi chapter 5.

Introduction

Introductory discussion, including the basic concepts and definition of "convex polygon".

Giloi's Definition of H.S.A.

Discussion of Giloi's definition, including perspective projections, intersection functions, containment tests and visibility functions.

Taxonomy of Hidden Surface Algorithms.

Taxonomy and methods. This includes Giloi's classification based on the form of the input data as well as other classifications based on the type of method to be applied. These include Scan-line methods (e.g. Watkins' Method), List-priority methods (e.g. Encarncao's Priority method), Ray-tracing methods (e.g. Appel's method) and Methods for curved surfaces (e.g. Encarnacao's Scan- Grid method).

Coherence.

Some of these methods use the concept of "coherence" to improve their efficiency.

The individual methods discussed are:

Watkins' Method A scan-line method which may be applied to solids made up of plane polygonal facets.

Encarnacao's Priority Method. A list-priority method which may be applied to solids made up of triangular facets.

Appel's Method. A ray-tracing method which may be applied to solids made up of plane polygonal facets.

Encarnacao's Scan-Grid Method. A special method for objects made up of surface patches forming curved facets.