Creating a conic given three points

The 3 points and 2 tangents method of the Conic Curve command enables you to create a conic arc defined by its endpoints, the tangency conditions in such endpoints and a third point the conic must be through.

After starting the Conic Curve command, proceed as follows.

1 In the Type drop-down list, select 3 points and 2 tangents.
2 Specify the two endpoints of the conic arc and a third point by clicking or by using a snap command.



To change the selected points, right-click on Points, select Reset in the context menu and specify the new points.

As soon as the third point is selected, the Tangents Group is displayed:
3 For each of the two endpoints, specify the tangency condition in on of the following ways:
  • In the First Tangent and Second Tangent drop-down lists under Tangents Group, select:
    • In the 1st Tangent and 2nd Tangent drop-down lists under Tangents Group, select the desired direction (see " How to define an axis or a line" for details).
  • Use the handles:
    • The three arc represent s the three angle s of revolution (about X, about Y, about Z). You can rotate the tangent vector about an axis by dragging the corresponding arc or by typing the value of the rotation into the Angle box which shows up when you pick the arc
    • The longest red line represents the tangent vector: you can pick its free endpoint and move it around in the space until you assign the tangent vector the desired direction.
4 A preview is immediately displayed.



Click or to confirm your selections and create the curve.



Click to discard your changes.