Hi, I'm working in GRASS 6.4.0 and using v.buffer applied to an extents rectangle. For some reason v.buffer is producing one chamfered corner in the buffered vector.
The command I used was: v.buffer -s -c --overwrite input=c83a_extents@PERMANENT output=c83a_extents_5km_buffer@20m_DEM distance=5000. Buffering lines... Buffering areas... Building topology for vector map <c83a_extents_5km_buffer>... Registering primitives... 1 primitives registered 12 vertices registered Number of nodes: 1 Number of primitives: 1 Number of points: 0 Number of lines: 0 Number of boundaries: 1 Number of centroids: 0 Number of areas: - Number of isles: - Snapping boundaries... Breaking boundaries... Removing duplicates... Attaching islands... Building topology for vector map <c83a_extents_5km_buffer>... Building areas... 1 areas built 1 isles built Attaching islands... Number of nodes: 1 Number of primitives: 1 Number of points: 0 Number of lines: 0 Number of boundaries: 1 Number of centroids: 0 Number of areas: 1 Number of isles: 1 Number of areas without centroid: 1 Attaching centroids... Building topology for vector map <c83a_extents_5km_buffer>... Attaching centroids... Number of nodes: 2 Number of primitives: 2 Number of points: 0 Number of lines: 0 Number of boundaries: 1 Number of centroids: 1 Number of areas: 1 Number of isles: 1 Building topology for vector map <c83a_extents_5km_buffer>... Registering primitives... 2 primitives registered 13 vertices registered Building areas... 1 areas built 1 isles built Attaching islands... Attaching centroids... Number of nodes: 2 Number of primitives: 2 Number of points: 0 Number of lines: 0 Number of boundaries: 1 Number of centroids: 1 Number of areas: 1 Number of isles: 1 (Wed Apr 20 14:08:46 2011) Command finished (1 sec) I have placed a screenshot of the outcome on the web <http://www.nedbib.za.net/v.buffer.png>. The region was set to the DEM raster in the background. The black triangle is the extents and the red one the buffered polygon. Does someone know why v.buffer would create such a chamfered corner. I've played around with selecting different feature types and adding a minor distance value, but I always get the same result. Thanks Hanlie _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
