Constructive Synthetic Geometry
نویسنده
چکیده
In the current problem set we are investigating two problems in computational geometry using concepts from our study of the computable real numbers and calculus. The main problem we are examining is the notion of a set of points in the plane and how to compute their convex hull. In the last lecture we briefly discussed how it is possible to investigate computational geometry in a more abstract manner, in the spirit of Euclidean geometry. In such an approach we start with an abstract type of Points. We do not need to think that these will be represented as real numbers. We can imagine them as “points in the plane” and state the properties of line segments, angles, triangles, polygons, and so forth using abstract axiomatic mathematics in the spirit of Euclid, but with more precision. This is the way algebra is usually presented as we have seen in looking about the algebraic properties of the rational and reals. Both of these types of numbers satisfy the algebraic properties of a field. We can define this concept without reference to any specific instances. We are interested in the general properties of any field.
منابع مشابه
A Constructive Real Projective Plane
The classical theory of plane projective geometry is examined constructively, using both synthetic and analytic methods. The topics include Desargues's Theorem, harmonic conjugates, projectivities, involutions, conics, Pascal's Theorem, poles and polars. The axioms used for the synthetic treatment are constructive versions of the traditional axioms. The analytic construction is used to verify t...
متن کاملRealistic Display of Volumes D
e o We present a method for recursively rendering a realistic image of a volumetric dataset consisting of a mixtur f sampled and synthetic objects. We describe several volume visualization tools that are based on the use of recurl w sive ray tracing. These include shadows, mirrors, specularity, and constructive solid geometry. We discuss severa ays to enhance our method both in terms of image q...
متن کاملDiscussing two topics: Synthetic Geometry and Atlantic Article
We are gradually becoming familiar in the last three lectures with an approach to geometry in the style of Euclid, using abstract primitive concepts such as points, lines, polygons, congruence and so forth and with proving theorems that show the existence of geometric objects such as equilateral triangles and with performing certain constructions such as bisecting a line segment or an angle or ...
متن کامل3d Shape Coding with Superquadrics
We present a geometric coding method for 3D real and virtual objects transmission and visualization. We describe object surfaces with a set of superellipsoids which are structured with a constructive solid geometry (CSG) tree. An unstructured cloud of 3D points lying on the original object surface is considered as initial data. The tree is obtained using a split and merge algorithm. At each spl...
متن کاملSpeed-ups in Constructive Solid Geometry
We convert constructive solid geometry input to explicit representations of polygons, polyhedra, or more generally d-dimensional polyhedra, in time O(n), improving a previous O(n log n) bound. We then show that any Boolean formula can be preprocessed in time O(n log n/ log logn) so that the value of the formula can be maintained, as variables are changed one by one, in time O(log n/ log logn) p...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2017