Bufferer
From fmepedia
Bufferer is a Workbench Transformer.
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Description
The Bufferer creates a buffer with a certain width around objects. The Bufferer offers a number of options for Buffer style, which control the end cap and the side to which the buffer is placed.
For very complex objects, it's highly recommended to use a LineGeneralizer or AreaGeneralizer before buffering, as this will dramatically speed up the process. Also, in case of buffering lines, a LineJoiner and/or Snapper may work wonders.
Buffer Output and Aggregates
A group-by in the Bufferer also results in an aggregation of non-overlapping buffers with the same group-by attribute values. This is intended behaviour. Reverse this functionality using a Deaggregator transformer.
Example 1
The attached workspace shows an example use of the Bufferer transformer.
In this example a line feature is generated and buffered several times, using slightly different styles each time.
Workspace Screenshot
Output Screenshot
The order of features is reverse to the workspace; from the top down they are...
- Right side only (source line runs from left to right)
- Left side only (source line runs from left to right)
- Both sides
- Cap Projecting
- Cap Butt
- Cap Round
Example 2
The attached workspace shows an example use of the Bufferer transformer.
In this example (like this related Dissolver example) a GPS dataset consists of a number of waypoints. The waypoints are buffered, where the buffer size is proportional to the vehicle speed at that point. The idea is to show areas where vehicle speed is low to indicate possible areas of traffic congestion.
Workspace Screenshot
Output Screenshot
The narrower areas indicate slower moving traffic...
