Invert Buffer?

[Olakalen]

[ATTACH=CONFIG]19596[/ATTACH]Hi

I have a line layer of a road network around which I create a buffer zone of 1000 m with Analysis Tools>Proximity>Buffer. But I am
interested in the white areas outside the red buffer zone, and not the buffer zones themselves.

Is there a way to invert the buffer, or which is the best way to pick out the the polygons outside the buffer area?

Thanks,

Ola

[DavidPetrey1]

Ola,

Try the following:

-Use the Feature Envelope To Polygon tool to give a bounding box polygon from the buffered dataset (or just create a new polygon dataset and draw a large rectangle that covers all the buffered data).
-If you have an ArcInfo/ArcGIS for Desktop Advanced licence simply use the Erase tool.
-Otherwise first use the Dissolve tool to create 1 polygon from your buffered data. Then Started Editing the new Envelope dataset. With the Envelope and the Dissolved buffer onscreen Select just the Dissolved buffer polygon and choose Clip from the Editor drop-down menu on the Editor Toolbar. Choose to 'discard the area that intersects' when a message appears and you will be left with your reverse buffer clipped out of your Envelope dataset.

If this helps please mark the question as answered to let others know.

Thanks,

David
simplyGIS Ltd. Making GIS simple
www.simplygis.co.uk/GISTraining.html