/// <summary>
/// Add an offset curve for a ring.
/// The side and left and right topological location arguments
/// assume that the ring is oriented CW.
/// If the ring is in the opposite orientation,
/// the left and right locations must be interchanged and the side flipped.
/// </summary>
/// <param name="coord">The coordinates of the ring (must not contain repeated points).</param>
/// <param name="offsetDistance">The distance at which to create the buffer.</param>
/// <param name="side">The side of the ring on which to construct the buffer line.</param>
/// <param name="cwLeftLoc">The location on the L side of the ring (if it is CW).</param>
/// <param name="cwRightLoc">The location on the R side of the ring (if it is CW).</param>
private void AddPolygonRing(ICoordinate[] coord, double offsetDistance,
Positions side, Locations cwLeftLoc, Locations cwRightLoc)
{
Locations leftLoc = cwLeftLoc;
Locations rightLoc = cwRightLoc;
if (CGAlgorithms.IsCCW(coord))
{
leftLoc = cwRightLoc;
rightLoc = cwLeftLoc;
side = Position.Opposite(side);
}
IList lineList = curveBuilder.GetRingCurve(coord, side, offsetDistance);
AddCurves(lineList, leftLoc, rightLoc);
}
