CAD4(国外英语资料).doc

CAD4(国外英语资料) CAD education network produced fourth, two-dimensional basic graphics rendering two Content and requirement: Two dimensional graphics are made up of some basic graphics, such as dots, lines, circles, and so on. To draw a two-dimensional graph, you should first familiarize yourself with the drawing commands of the basic graphics. This lesson focuses on circular, elliptical, arc, ring, polyline, spline, multi line rendering methods. Through the study of this course, readers should achieve the following goals: L understands all kinds of commands for drawing circles and arcs. They can select the appropriate method according to the specific situation and quickly complete the circle or arc drawing. L understands the meaning of the command options in drawing ellipses and accurately draws ellipses according to size requirements. L grasps the circle drawing method. L grasps polyline, spline, multi line rendering method, and understands their respective characteristics. 4.1 draw circle CAD education network production Using the Drawing toolbar, you can draw a circle. Click the command window to indicate the center of the circle, or select the different rendering methods for the circle, as shown in Figure 4-1. The meaning of the command options in the brackets is as follows: Figure 4-1 L [three point (3P)]: draw circles through three points on the circle. After entering 3P, the system prompts the first, second, and third points on the specified circle. L [2] (2P): draw a circle through two points to determine the diameter of the. After entering the 2P, the system prompts the first and second endpoints of the diameter of the specified circle, respectively. L [tangent, tangent, radius (T)]: draw the circle through two tangents and radii, enter T, and then indicate the first tangent and the second tangent point of the circle and the radius of the circle respectively. In addition, click the menu [drawing] [circle] [tangent, tangent, tangent] command, you can choose