Page Comparison

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  <wms:mapengine id="test">
    ...
    <selection>
      <limit>5000</limit>
      <timeout>5</timeout>
    </selection>
  </wms:mapengine>

Both of these setting settings can help ensure a speedy map response even if the user has a large number of selected features.

...

  <wms:mapengine id="test">
    ...
    <selection>
      <antialiasing>false</antialiasing>
    </selection>
  </wms:mapengine>

Also, since the The selected features are drawn in batches and you can alter the number of features that are drawn in each batch. The default batch size is 1000.
Increasing this value will will reduce the overhead that 's is required for each batch but sometimes there are limits on the underlying infrastructure (database or spatial engine) that limit the number of features that can be retrieved at once. You can try increasing this value and selecting more than that many features and see if the selection is still drawing, if . If it is then it 's is safe to use the new limit value, otherwise it should be reduced until a safe value is determined. There 's is little point in setting this value to more than the limit value, if it has been set.

  <wms:mapengine id="test">
    ...
    <selection>
      <batchsize>2500</batchsize>
    </selection>
  </wms:mapengine>

You can also gain a few more milliseconds by telling the selection drawing plugin to reuse the original image on which to draw the selection rather than creating a new one.
Since there There are a large number of possible image formats (in regards to bits-per-pixel, colour palettes, transparency support, etc) that the underlying map engine can produce, by . By default, the selection drawing plugin will generate a new image of a known format and "draw" the original map image on it before drawing the selection on top, . In this way, a consistent image format is produced at the end (this is mainly to handle problems experienced with earlier versions of Internet Explorer).

If the map engine that you are using produces images that are directly suitable for display in the browser then you can tell the selection drawing plugin to simply draw the selection on top of the original image and forward that on to the client. It . This is done by setting reuse to true. It is up to you to make sure that the image supports the correct transparency requirements , and that it works in the browsers you want to support, etc. This is done by setting reuse to true.. 

  <wms:mapengine id="test">
    ...
    <selection>
      <reuse>true</reuse>
    </selection>
  </wms:mapengine>

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