Snapper

Features whose geometry is changed by the transformer.

Features that leave the transformer without being changed.

If通过...分组选择属性，功能仅按属性将其捕获到具有相同值的其他功能。

笔记：平行处理如何与FME一起使用：见About Parallel Processingfor detailed information.

This parameter determines whether or not the transformer should perform the work across parallel processes. If it is enabled, a process will be launched for each group specified by the通过...分组parameter.

Parallel Processing Levels

例如，在四核机器上，最小的并行性将导致两个同时的FME进程。8核机上的极端并行性将导致16个同时流程。

您可以尝试此功能，并在Windows任务管理器和Workbench日志窗口中查看信息。

Yes: This transformer will process input groups in order. Changes on the value of the通过...分组输入流上的参数将触发当前累计组上的批处理。如果组很大/复杂，则会提高整体速度，但如果输入组未真正订购，则可能导致不期望的行为。

不: This is the default behavior. Processing will only occur in this transformer once all input is present.

When this parameter is set toEnd Point Snapping, the transformer:

• Snaps lines together if the distance between their end points are within the specified tolerance.
• Snaps point features to points or lines if their distances are within the specified tolerance.
• Area features will not be altered by the transformer when run in this mode.
• When two features are snapped together, the feature that entered the factory most recently is the one that is modified

When this parameter is set to顶点捕捉, the transformer does the following:

• Snaps vertices of lines together if their distances are within the specified tolerance.
• Snaps point features to points or lines if their distances are within the specified tolerance.
• Area features are altered by this operation as its vertices are snapped.
• When two features are snapped together, the feature that entered the factory most recently is the one that is modified.

When this parameter is set toSegment Snapping, the transformer does the following:

• Snaps vertices of lines together if their distances are within the specified tolerance.
• 如果它们的距离在沿着段的任何点处的指定容差内，则将段的顶点捕捉到其他段。新顶点将被引入新的捕获顶点已移动到的段。
• 段捕捉可能导致重复点，其中段已退化为一个点。
• Segments which cross other segments will have new vertices introduced at the point of intersection, but the segments will remain unbroken.
• 由于其顶点和段捕获，该操作改变了区域特征。
• If a segment and a point are both within tolerance, the transformer will snap to a vertex in preference to a segment, even when the segment is closer.

Snapping Tolerance指定在特征之间发生捕捉的距离。

This parameter applies only when the end point of a feature is being snapped. It controls how lines are modified when they are snapped.

• 绝不: the endpoint of a line is moved when it is snapped and no additional vertex is added.
• ALWAYS: the original end point (start point) of the line becomes the second from the end (start) and a new vertex is added to complete the snap.
• forward_only: a new vertex is added only when doing so creates an angle greater than 90 degrees with the original line segment. In this case, if adding the vertex would cause a less than 90-degree angle, the old end point is still moved.

Any features entering the transformer whose length is less than or equal to the tolerance will be treated specially: they will be output asUntouched, and other features (but not other short features) will not be able to snap to them. If the option is not selected, features like this will collapse to a single point and will be dropped.