Select this mode to add a vertex to the polygon/polyline. The vertex can be any of the following: corner, Bézier, cubic, radius, or fillet (circular arc).
To reshape a 2D polyline or polygon by adding a vertex:
Select the polyline or polygon to change.
Click the Reshape tool from the Basic palette.
Click the Add Vertex mode from the Tool bar.
From the Tool bar, select the type of control point for the new vertex.
Move the cursor to an existing vertex near the location where the new vertex is to be added. The cursor becomes an arrow with two black diamonds when a vertex can be added.
Clicking on the handle at a center point along an edge adds a new vertex exactly at that center point.
Drag the cursor to the desired location for the new vertex.
Click at the new location.
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