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C00002 00002	4.0 MEMORY  -  DATA STRUCTURES.
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4.0 MEMORY  -  DATA STRUCTURES.

	4.0	Introduction.

	4.1	The Winged Edge Polyhedron Representation.
	4.2	Three Image Representations: Video, FEV and CRE.
	4.3	Representation of a 3-D Visual Mental Universe.

	4.4	Other Geometric Entities.
	4.5	GEOMED Node Formats.
	4.6	CRE Node Formats.

	4.7	Critique

PART TWO. PROGRAMMING.

	The next three chapters describe a geometric vision modeling
system consisting of two programs named GEOMED and CRE.


4.0 Introduction to Geometric Data Structures.

	In order to get a computer to deal with the physical world it
must  have  a  data representation  on  which  computations involving
space, time, shape, size and the appearance of things can be done. In
this  chapter,  a  particular representation  for  physical  objects,
images and  associated entities is explained. The data structures has
been implemented  as small  blocks of words  containing pointers  and
data in the fashion usual to graphics and simulation; an introduction
to this  technology  can  be  found in  Knuth.  Although  the  latest
language of implementation  is PDP-10 machine code,  earlier versions
were coded in LISP and SAIL with LEAP.