cgal_buffer_linestring - ObjectVision/GeoDMS GitHub Wiki
Geometric functions > cgal_buffer_linestring
- cgal_buffer_linestring(arc_data_item, buffer_distance, nrPointsInCircle)
cgal_buffer_linestring(arc_data_item, buffer_distance, nrPointsInCircle) creates a buffer polygon around each arc (linestring) in the arc_data_item. The result is a polygon data item with the same domain as the arc_data_item.
The buffer_distance is a Float64 value that specifies the width of the buffer (on each side of the line) in the units of the coordinate system.
The nrPointsInCircle is a UInt8 value that specifies the number of points used to approximate rounded end-caps and corner joins. A higher value results in a smoother buffer but increases computation time. The minimum value is 3.
The cgal_ prefix of the function name indicates that the implementation of the operator uses CGAL, which provides exact predicates and exact constructions for maximum numerical precision.
- attribute arc_data_item with a point value type and arc composition
- parameter buffer_distance with a Float64 value type
- parameter nrPointsInCircle with a UInt8 value type
- The composition type of the arc_data_item needs to be arc.
- buffer_distance must be a positive value.
- nrPointsInCircle must be at least 3.
14.0
attribute<dpoint> buffer_geometry (road) := cgal_buffer_linestring(road/geometry, 25.0, 8b);