Coordinate System of AutoCAD

 

The coordinate system of AutoCAD is divided into world coordinate system and user coordinate system.

1 World coordinate system (WCS)

Figure 1-1-1

The world coordinate system is the default coordinate system defined by the AutoCAD System. When we open a new graph, we enter the world coordinate system. It is similar to the familiar dikar coordinate system. The horizontal axis is the X axis, the vertical axis is the Y axis, and the zaxis is determined by the right-hand spiral law.

After entering AutoCAD, we will find that there is a coordinate icon (ucsicon) in the lower left corner of the drawing area, as shown in 1-1-1 (a). When the coordinate icon is displayed at the coordinate origin, it is displayed in the shape of 1-1-1 (B, E) (E is the southwest view ). There is a w on each of these graphic symbols, which represents the world coordinate system. In addition, when we observe a graph in 3D mode, the coordinate icon will be similar to C and D in Figure 1-1-1 (D is in the southwest view ).

In AutoCAD, the world coordinate system is uniquely determined. In this way, the description of some points in a drawing, especially in a 3D drawing, becomes complex, we introduced the user coordinate system in AutoCAD.

2 user coordinate system (UCS)

The user coordinate system is a coordinate system defined by the user. The user coordinate system is not unique. It can change the direction, move, and rotate at will. With the UCS function of AutoCAD, you can easily draw 3D graphics objects.

The coordinate icons of the user coordinate system are different from those of the world coordinate system. They are not marked with W in the coordinate icons, as shown in F and G in 1-1-1. In addition, when we observe the image in 3D mode, the coordinate icon is the same as the world coordinate system.