Edge Tangency Options Dialog

The Edge Tangency Options dialog is used to control the tangency condition along the particular patch edge for which the dialog has been activated. Having set the required options (listed below) click Apply to update the affected geometry of the patch.

Once the dialog is open, to edit the tangency conditions for another patch edge, double clicking the corresponding tangency control, makes it the subject of the dialog.

The Defaults and Close buttons restore the default settings and close the dialog respectively.

The available edge tangency options are:

• Tange into mating edge - If selected, the edge is passive, that means, it picks up its edge tangency from its mating patch edge to achieve a smooth join. If this option is checked for both of a pair of mating edges, the a smooth join is achieved by allowing both edges to move.

• Include patch corners - If selected, the second and penultimate tangent ribbon control points are included in modifications to the edge. These control points affect two tangent ribbons, and are also controlled by the corner tangency controls.

• Sweep ribbon Control Points - If selected, the initial positions of the tangent ribbon control points are found by sweeping or lofting between the first and last tangent ribbon control points. This usually produces a reasonable tangent ribbon.

• Allow Control Points to slide during patch fitting - If selected, the tangent ribbon control points, (the line of control points adjacent to the edge that determines the edge tangency) can move during the patch fitting process. The movement is constrained to lines that ensure continuity of tangency is preserved, if this is required. Then the direction of the tangency is constrained but not its magnitude.

See also Changing tangency conditions and Edge Tangency Options Dialog.