The composition method and the used template of the visual diagram of the sphere and its North Pole

Abstract

The invention discloses a sphere illustrative diagram, a composition method of the North Pole position thereof and a used template. The used template is characterized by comprising a meridian template and a latitude line template. The method of using the template to determine the North Pole position comprises the steps: in the T parallel projection direction, a sphere center O is taken as a circle center, the minor semi-axis of an equator ellipse is used as a radius for drawing a circle, and the circle and the major semi-axis of the equator ellipse intersect at a point A; the points A and O are connected; a vertical line of AO is drawn through the circle center O toward the North Pole direction of a sphere and intersects with a contour circle of the sphere at a point D; a vertical line of AO is drawn through the point A toward the North Pole direction of the sphere and intersects with the contour circle of the sphere at a point B; a parallel line of AO is drawn through the point B to obtain a point of intersection C where the parallel line intersects with DO, and the point of intersection C is the North Pole position of the sphere illustrative diagram. The determination method of South Pole position and the determination method of the North Pole position are identical, but the directions are opposite. Meridians of the sphere are drawn through the North Pole and the South Pole to complete the drawing of the sphere illustrative diagram. The meridians and latitude lines of the sphere in a general state can be conveniently drawn by the template.

Description

technical field [0001] The present invention relates to a drawing method of a visual diagram of a sphere and a template used therefor, and in particular discloses a composition method of a visual diagram of a sphere and the position of the North Pole and a template used therefor. The template of the present invention is a school stationery and is a Tool template for drawing visual diagrams of spheres. Background technique [0002] On a two-dimensional plane, a figure with a three-dimensional effect drawn is called an intuitive figure. By choosing an appropriate oblique parallel projection direction, an oblique dimetric direct view can be obtained. Therefore, the obtained oblique dimetric intuitive diagram is actually a shadow, and the oblique dimetric intuitive diagram is an unintuitive intuitive diagram. Assuming that the line of sight is parallel, and the direction of the line of sight is along the direction of the parallel projection, the projection seen at this time is...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to solve the problem that the North Pole and the South Pole cannot be correctly positioned when drawing a direct view of a sphere in the prior art, and disclose a composition method and a template for a direct view of a sphere and the position of the North Pole. The template designed by the present invention , compatible with simple polyhedrons, and can also draw a real sphere visual diagram, which solves the unsolved problems in the current national standard textbooks

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