Features of Computer Images

Abstract

\uf0beAn important aspect of human activities is receiving, recording and operating with geometric information possessed by all real objects. It is far from always that a person can receive geometric information directly from the object. In these cases substitutes (geometric models) of these objects, which carry the same geometric information, are used. They are geometric models of three-dimensional objects that people traditionally use in their flat images. The main requirement imposed on geometric models is to save all geometric information of a source object. To meet these requirements, a flat image must be created in accordance with laws discovered early. Unfortunately when creating flat computer images, these laws are not always followed. As a result the received images do not follow the basic requirement distorting the represented depicted three-dimensional world. Key words\uf0beflat image, geometric information, geometric model I. IMAGES USAGE SIGNIFICANCE Why do people need images? The answer is known and obvious to everyone: to represent any geometric information. It is known that geometric information is information about dimensions, shape, objects, their relative position in space [3]. Is there any object in the real world that does not possess this information? And can a person exist in this world without the ability to perceive, represent and operate with this information? Of course, he cannot. The significance of geometric information can hardly be ever overestimated and it is difficult to find now and recently the period when people would not represent geometric information one way or another and would not process it. Images of three-dimensional objects on a plane (perspective, axonometry and Monge s projection) are most widely spread. These images perform the following functions [14]: \uf0b7 the illustrative and cognitive one being realized in fine arts and in the learning process (visual aids, training simulators). Images performing this function must correspond to the vision of a human eye distorting the reality. In other words, a human eye does not see parallelism; \uf0b7 the technological one being the basis for design, creation and operation of engineering and civil engineering projects. Images that perform this function must provide geometric information undistorted. Undoubtedly, both these functions testify to the wide usage of flat images in the most diverse areas of human activities [9, 10]. II. FEATURES OF IMAGES PERFORMING THE COGNITIVE AND ILLUSTRATIVE FUNCTION In general the requirements imposed on the images realizing the illustrative and cognitive function are the correspondence to such images that a human eye sees. What is the reality that a person sees? In terms of geometry the following principles depending on the physiology of an eye should be distinguished: \uf0b7 a human eye does not see parallel elements. As a result, all parallel lines of the same direction intersect at one point, called the vanishing point [15,16,18,19]; \uf0b7 all horizontal lines have vanishing points on the horizon locating on the horizon plane. Each person has his own horizon plane passing through his two pupils and serving as a gravity reference; \uf0b7 each human eye is restricted in width and height of an observed object. The range of the object vision is called the conventional cone of vision it is a set of rays reflected from the object and focused in a lens of a human eye (Fig. 1). The maximum value of the angle of this cone is 600. If an object does not fit this cone to see it, a person must shift his gaze or change his position; \uf0b7 each conditional cone of vision has the main ray it is a virtual line that passes through a lens of an eye and an approximate center of an eyeball. The closer the subject area of the object is to the main ray, the sharper the image is. In the conventional cone of vision the main ray occupies the central position and is oriented toward the conditional center of an object (Fig. 1); \uf0b7 images of objects are displayed on a curve of a surface of a human eye back [1]; \uf0b7 a human eye does not see parallel straight lines, all parallel lines of the same direction intersect at one point (the vanishing point); \uf0b7 the virtual plane of the horizon passes through two pupils of human eyes, and serves as a gravity reference [15, 16, 17, 18, 19]. International Conference on Communicative Strategies of Information Society (CSIS 2018) Copyright © 2019, the Authors. Published by Atlantis Press. This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/). Advances in Social Science, Education and Humanities Research, volume 273