Avoid warning from Geotools StreamingRenderer: Rendering Buffer

Question

In our application we get a warning from the method

org.geotools.renderer.lite.StreamingRenderer.findRenderingBuffer(..)

  WARNUNG: Assuming rendering buffer = 0, but estimation is not 
  accurate, you may want to set a buffer manually.

The message appears when a layer containing lots of polygons is drawn at a very small scale. The style of the polygons defines an extra stroke for their outlines.

EDIT: This happens when using Stroke.NULL for the outline of polygons. It does not happen, when an individual stroke is set.

What is the reason for this message and how can it be avoided?

Thank you

Answer 1

This occurs when the buffer that needs to be added to the rendering area can't be calculated exactly - There are a few places where estimateAccurate is set to false (which triggers that warning) - something to do with the width of the stroke or the size of a graphic usually.

So you may have an SLD problem.