Draft Snap/zh-cn

描述
在底图工作台工具中，您可以通过指针单击3D视图来拾取图形中的点、距离、半径与角度.

捕捉功能可用于底图工作台与建筑工作台（Arch Workbench）中的大多工具，利用捕捉工具栏中的按钮即可对此功能进行全局开启或关闭. 而通过菜单便可以激活捕捉工具栏. 通过点选捕捉工具栏中的各按钮，即可开启或关闭对应的捕捉方法.



Snap tools
These tools are available in the Draft Snap toolbar and in the Draft snap widget.

Note that circular edges do not have to be full circles.


 * [[Image:Draft_Snap_Lock.svg|32px]] Snap Lock: enables or disables snapping globally.


 * [[Image:Draft_Snap_Endpoint.svg|32px]] Snap Endpoint: snaps to the endpoints of edges.


 * [[Image:Draft_Snap_Midpoint.svg|32px]] Snap Midpoint: snaps to the midpoint of edges.


 * [[Image:Draft_Snap_Center.svg|32px]] Snap Center: snaps to the center point of faces and circular edges, and to the point of Draft WorkingPlaneProxies and Arch BuildingParts.


 * [[Image:Draft_Snap_Angle.svg|32px]] Snap Angle: snaps to the special cardinal points on circular edges, at multiples of 30° and 45°.


 * [[Image:Draft_Snap_Intersection.svg|32px]] Snap Intersection: snaps to the intersection of two edges.


 * [[Image:Draft_Snap_Perpendicular.svg|32px]] Snap Perpendicular: snaps to the perpendicular point on edges.


 * [[Image:Draft_Snap_Extension.svg|32px]] Snap Extension: snaps to an imaginary line that extends beyond the endpoints of straight edges.


 * [[Image:Draft_Snap_Parallel.svg|32px]] Snap Parallel: snaps to an imaginary line parallel to straight edges.


 * [[Image:Draft_Snap_Special.svg|32px]] Snap Special: snaps to special points defined by the object.


 * [[Image:Draft_Snap_Near.svg|32px]] Snap Near: snaps to the nearest point on faces or edges.


 * [[Image:Draft_Snap_Ortho.svg|32px]] Snap Ortho: snaps to imaginary lines that cross the previous point at 0°, 45°, 90° and 135°.


 * [[Image:Draft_Snap_Grid.svg|32px]] Snap Grid: snaps to the intersections of grid lines.


 * [[Image:Draft_Snap_WorkingPlane.svg|32px]] Snap WorkingPlane: projects the snap point onto the current working plane.


 * [[Image:Draft_Snap_Dimensions.svg|32px]] Snap Dimensions: shows temporary X and Y dimensions.


 * [[Image:Draft_ToggleGrid.svg|32px]] Toggle Grid: switches the grid on or off.

Advanced snapping

 * Additional snap points can be obtained by combining two snap options. For example combining Draft Snap Ortho and Draft Snap Extension will give you a snap point at the intersection of their imaginary lines.
 * Snapping can be combined with constraining.
 * Press to insert a "hold point" at the current location of the cursor. You can snap to the orthogonal axes of hold points, and to the intersections of these axes. If the Draft Snap Midpoint option is active, you can also snap to the midpoint between two hold points.
 * Press one or more times to snap to an object that is obscured by other geometry. This is called "snap cycling". Note that you must move the cursor by a small amount in the 3D view after pressing the key.





Preferences
See also: Preferences Editor and Draft Preferences.

Note that after changing some preferences you must restart FreeCAD.


 * When a Draft or Arch command requiring point input is active, the maximum distance at which Draft Snap Grid detects the intersections of grid lines can be changed on-the-fly by pressing (increase key) or  (decrease key). This setting is stored: . It can also be changed in the task panel of the Draft SelectPlane command.
 * To only snap when the key is held down:
 * Deselect:.
 * The default key,, can be changed:.
 * To only show the Draft Snap toolbar when a command is active:
 * Select:.
 * Select:.
 * The snap symbols can be changed:.
 * The color of the snap symbols and the dimensions of Draft Snap Dimensions can be changed:.
 * The mentioned single character keyboard shortcuts can be changed:.