Once again I encounter something very strange with ArcGIS. I perform a buffer analysis on one side of a polyline. There seems to be a serious accuracy problem and I can't figure out what the cause is. So I hope to find some expertise out there…What I tried without success:
- change distance settings from 'Field' to 'Linear unit'
- change distance settings from 'Field' to 'Linear unit'
- change end type settings from 'ROUND' to 'FLAT'
- run check geometry tool on the line feature
- I made a copy of the line and shorted it to area of interest which had some effect but didn't resolve the problem entirely. Especially around the sharp angle the buffer still takes a shortcut!
The buffer is lurching up to 4 meters on the wrong side! See the picture I attached to get an better impression of the problem. Does anyone have an idea what might me causing this behavior? I'm using ArcGIS 9.3.1. with WinXP.
UPDATE
See also my comment below.
I performed the described series of actions (divide, intersect,..) to increase the accuracy level of the source data, placing a vertex every 3 meters along the line. There still remains inaccuracy, again the buffering around the rough turn especially is giving me trouble. See second pic.
Best Answer
I have had similar result when dealing with M and Z Polylines or polylines with arcs. I have had more success removing the M and Z value using X-Tools to "Flatten" the poly.