METHOD OF AND AN APPARATUS FOR RENDERING A THREE-DIMENSIONAL OBJECT BY A PLURALITY OF DOTS ON A TWO-DIMENSIONAL DISPLAY SCREEN IN A COMPUTER GRAPHICS SYSTEM

摘要

JA9-90-529 A METHOD OF AND AN APPARATUS FOR RENDERING A THREE-DIMENSIONAL OBJECT BY A PLURALITY OF DOTS ON A TWO-DIMENSIONAL DISPLAY SCREEN IN A COMPUTER GRAPHICS SYSTEM To display a body of rotation by dots on a two-dimensional screen, the surfaces forming the body are divided into a first domain with a relatively large change in the radius of gyration from the rotation axis and a second domain with a relatively small change in the radius of gyration from the rotation axis (e.g. polar domains and equatorial domain for a sphere) and dots are arranged in each domain according to different rules. That is, the dots whose number increases in accordance with the increase in the radius of gyration are arranged on concentric circumferences at an equal interval in the first domain and a certain number of dots are arranged on concentric circumferences at an equal interval in the second domain so that a dot on a concentric circumference is located between the dots on the adjacent concentric circumference. In the above-mentioned sphere, the dots whose number increases (e.g. in an arithmetic progression) in the direction from the poles to the equator are arranged on parallels of latitude at an equal interval in the polar domains and a certain number of dots are arranged on parallels of latitude at an equal interval in the equatorial domain so that a dot on a parallel of latitude is located between the dots on the adjacent parallel of latitude.