In general, you use four curves and the curves must each be open, but together form a closed loop. To use three curves, select 3 curves and the fourth curve field is disabled. If the corners do not match, you receive an error message, "unable to construct surface with these inputs."
To create a Coons surface.
- Select Construct tab > Surfaces panel > From Curves > Coons to display the Coons dialog.
- Optionally enter a name in the Surface name field.
- Optionally select 3 curves if you want to create a three-curve Coons surface.
- Select a curve from the
Curve 1 list, or click the
Pick Curve
button and select it in the graphics window.
- Select a curve from the
Curve 2 list, or click the
Pick Curve
button and select it in the graphics window. This curve must create a corner with
Curve 1.
- Select a curve from the
Curve 3 list, or click the
Pick Curve
button and select it in the graphics window. This curve must create a corner with
Curve 2, and if
3 curves is selected, this curve must create a corner with
Curve 1.
- If
3 curves is deselected, select a curve from the
Curve 4 list, or click the
Pick Curve
button and select it in the graphics window. This curve must create a corner with
Curve 1 and
Curve 3.
- Optionally select Reparameterize curves.
- Click the Preview button to display a preview of the surface in the graphics window.
- Click OK.