To Align One-Sided Edges with External Geometric References
1. Select a one-sided edge or a loop of one-sided edges of one or more shapes.
2. Click the arrow next to
Align on the
Freestyle tab to select one of the following align types:
◦ Align ◦ 
Align Tangent ◦ 
Align Normal ◦ 
Align Curvature 3. Select the external geometric reference. The external geometry can be an edge, curve, datum plane, planar surface, surface quilt, or a chain of curves or edges.
|  You can select external geometric references with G0, G1, or G2 continuity. |
4. Middle-click to align the selected mesh elements with the reference geometry. While aligning an edge or an open loop of edges with a closed chain reference, the segments of the closed chain will be highlighted. Select the required segment.
A glyph or connection icon is displayed on the referenced geometry when the external geometric reference is an edge or loop of edges
5. To change the alignment type, right-click the glyph and click Position, Tangent, Normal Position, or Curvature on the shortcut menu.
6. To change the referenced surface right-click the glyph and click Change Surface on the shortcut menu.
| • If you select surface quilt reference, only the Align type or position aligning is available. • This option is available when the external geometric reference is a two-sided edge or a loop of edges and the alignment type is Tangent or Curvature. |
To change the scale of the glyph or connection icon, click Operations > Options. The Freestyle Options dialog box opens. Type the appropriate value in the Connection icon scale box.
7. To break the associativity between the Freestyle geometry and its associated external reference, click
Unlink. The glyph disappears from the referenced geometry.