Draft Arc 3Points/zh-cn

描述
底图三圆周点绘弧工具通过输入4个点：中点、半径、第一个点、最后一点，或拾取的切线，或上述若干组合，在当前的工作平面上创建一条圆弧. 它将根据Draft Tray中的Draft Linestyle设置来创建对应圆弧.

A Draft Arc is in fact a Draft Circle with a that is not the same as its.



如何使用
See also: Draft Tray, Draft Snap and Draft Constrain.


 * 1) 按下按钮，或先按键再按键.
 * 2) 在3D视图中点击第一个点，或输入一个坐标并按下按钮.
 * 3) 在3D视图中点击第二个点，或输入一个半径值.
 * 4) 在3D视图中点击第三个点，或输入一个起始角度.

选项
The single character keyboard shortcuts available in the task panel can be changed. See Draft Preferences. The shortcuts mentioned here are the default shortcuts.


 * To manually enter coordinates enter the X, Y and Z component, and press after each. Or you can press the  button when you have the desired values. It is advisable to move the pointer out of the 3D view before entering coordinates.
 * Press or click the  checkbox to toggle relative mode. If relative mode is on, coordinates are relative to the last point, if available, else they are relative to the coordinate system origin.
 * Press or click the  checkbox to toggle global mode. If global mode is on, coordinates are relative to the global coordinate system, else they are relative to the working plane coordinate system.
 * Press or click the  checkbox to toggle continue mode. If continue mode is on, the command will restart after finishing, allowing you to continue creating arcs.
 * Press to switch Draft snapping on or off.
 * Press or the  button to abort the command.

Preferences
See also: Preferences Editor and Draft Preferences.


 * To change the number of decimals used for the input of coordinates:.
 * If the option is checked, the command will create a non-editable Part Feature instead of a Draft Circle.

属性
弧对象享有Draft Circle中的所有属性，但是有些属性仅对圆形而言才有意义.

脚本
Draft API 与 FreeCAD Scripting Basics.

See also: Autogenerated API documentation and FreeCAD Scripting Basics.

To create a Draft Arc by 3 points use the method of the Draft module:


 * Creates an object from the given  list.
 * If a is given, the center of the circular arc will be moved to this place. See Placement for more information.
 * If is, the arc will make a face, that is, it will appear filled.
 * If is given, it is a, that is, a list indicating an object and a subelement of that object. This is used so that the object appears referenced to this support.
 * For example:.


 * If is given, it is a string defining a type of mapping, for example: ,  , etc. See Part EditAttachment for more information.
 * If is, the arc created will be a simple Part Feature, not a complex Draft object.

Example: