JOIN command
Joins 2D entities at their common endpoints.
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Description
Joins lines, lightweight and old-style 2D polylines, 3D polylines, arcs, elliptical arcs, polyarcs, splines, and helices at their common endpoints.
Note: The type of the resulting entity depends on the types of
the input entities and on their coplanarity.
Method
Two 2D polylines are joined into a single:
- 2D polyline- when they are coplanar.
- 3D polyline- when they are not coplanar and if they are composed only of straight segments.
- Spline- when they are not coplanar and if at least one of the polylines has a bulged (arc) segment.
A 2D polyline and a 3D polyline are joined into a single:
- 2D polyline: when they are coplanar.
- 3D polyline: when they are not coplanar and if the 2D polyline only has straight segments.
- Spline: when they are not coplanar and if the 2D polyline has at least one arc segment.
A line and a circular arc (or a polyline with arcs) are joined into a single:
- 2D polyline: when they are coplanar.
- Spline: when they are not coplanar.
The following pairs of entities are joined into a spline:
- Line and an elliptical arc.
- Spline and another open entity, such as an elliptical arc or polyline.
- Helix and another open entity, such as a line or arc.
Even when there are gaps between these entities, the command joins them into a single entity:
- Collinear lines: joined into a single line.
- Coplanar arcs (with same radii and center points): joined into an arc or a circle.
- Coplanar elliptical arcs (with same major and minor axes): joined into an elliptical arc or ellipse.
Circular and elliptical arcs are joined in a counterclockwise direction starting from the source arc.
Note: Collinear means the entities lie in the same imaginary
line. Coplanar means the entities lie in the same plane.