Activates continuity control at the seams. When this option is off, the operator does not fix the seams. This allows you to
adjust the subsurfaces before turning this option back on again.
Continuity
The degree of continuity maintained at the seams:
C0 (Position). The point is joined by a straight line segment.
C1 (Tangent). The point is joined by a smooth curve segment and the tangent does not change abruptly.