Change Vertex Mode Select this mode to change an existing vertex to a different type of control point: corner, Bézier, cubic spline, or fillet (circular arc) point. To reshape a 2D polyline or polygon by changing a vertex: 1. Select the polyline or polygon to change. 2. Click the 2D Reshape tool from the Basic palette. 3. Click the Change Vertex mode button. 4. From the Tool bar, select the new type of control point for the vertex. Change vertex does not work on a midpoint handle. Select only a vertex point. 5. Click to change the vertex.