Ref. Geometry  >> Create >> Sphere > From Surface

• Ref.Geometry >> Create >> Sphere > From Surface command creates a Ref.Sphere fitting a NURBS surface

Step   

Execute Ref.Geometry >> Create >> Sphere > From Surface: as follow

1. Select Ref.Geometry >> Create >> Sphere > From Surface from the menu or click the icon from the reference toolbar

2. Select surface to be Ref.Sphere

Result