Construction Aid Tangent > Object - Point (Construct Menu)

This command draws a Construction Aid endless line which begins at a given point and runs tangent to an ellipse or circle.

Any circle or ellipse which exists on its own or as part of another object can be identified as a reference object. This can also be the arc of an ellipse segment or a circle arc within a surface.

The position at which the (part) object is identified (the "ID point) affects the way in which the rest of the command is carried out. A tangent to a circle or ellipse can be drawn to either side of the circle or ellipse. The tangent point which is nearer to the ID point is used as the end point for the line.

The point through which the tangent should run can be entered with the mouse by clicking anywhere in the drawing. The tangent is dropped from this point to the object to work out the second point of the tangent.

This command does not function if the entered point is on the object outline or inside the object. In this case point entry is refused.