To Display Tangency
Click on the Graphics toolbar. The tangency conditions on the wireframe are displayed using arrows that point from the primary surface to the secondary surface. This option is only available if the Wireframe display is active.
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Click again to hide the tangency conditions.
Tangency display is only available when wireframe is displayed.
If you disable Wireframe display by clicking the display of the tangency conditions are also automatically disabled since tangent constraints cannot be displayed independently of the wireframe.
If a wireframe curve corresponds to a tangent edge, the arrow in the corresponding tangency condition is displayed in yellow.
If a wireframe corresponds to a tangency condition that is not satisfied, this tangency condition is displayed in black.
You can move the pointer over the tangent display, right-click, and select a different tangency condition to be applied. You can flip the tangency or convert it to symmetric tangency. Flipping the tangent switches the primary-secondary relationship of the two surfaces that share the tangency constraint.