The following list highlights key elements of the surface interrogation functionality available in SISL.

• Create and Initialize an Instance of an Intersection Curve

• Free the Space Occupied by an Intersection Curve

• Find the Intersections

  • Between SISL Curve and a Plane
  • Between SISL Curve and a Sphere
  • Between SISL Curve and a Cylinder
  • Between SISL Curve and a Cone
  • Between SISL Curve and an Elliptic Cone
  • Between SISL Curve and a Torus

• Find the Intersections

  • Between SISL Surface and a Point
  • Between SISL Surface and a Straight Line
  • Between SISL Surface and a Circle
  • Between SISL Surface and a SISL Curve

• Find the Topology of the Intersection

  • Between SISL Surface and Plane
  • Between SISL Surface and Sphere
  • Between SISL Surface and Cylinder
  • Between SISL Surface and Cone
  • Between SISL Surface and Elliptic Cone
  • Between SISL Surface and Torus
  • Between Two SISL Surfaces

• Find the Topology of the Silhouette of a Surface
  Find the topology of the silhouette of a SISL Surface using parallel projection, perspective projection or circular silhouette. The silhouette curves and points are described by guide parameters stored in an intersection curve object.

• March the Intersection Curve
  The intersection curve is described by guide parameter pairs stored in an intersection curve object and the marching generates the geometry of the intersection curve.

  • Between SISL Surface and Plane
  • Between SISL Surface and Sphere
  • Between SISL Surface and Cylinder
  • Between SISL Surface and Cone
  • Between SISL Surface and Elliptic Cone
  • Between SISL Surface and Torus
  • Between Two SISL Surfaces

• March a Silhouette of a Surface
  To generate the geometry of the silhouette curve by marching, using parallel projection, perspective projection or circular silhouette. The silhouette curves and points are described by guide parameters stored in an intersection curve object.

• Check if a Surface is Closed or has Degenerate
  Edges To check if a SISL surface is closed or has degenerate edges.

• Pick the Parameter Ranges of a Surface
  To pick the parameter ranges of a SISL surface.

• Find Closest Point Between a Surface and a Point
  To find the parameter values on a SISL surface, that when evaluated, are closest to a given point. The quicker simple version will find exactly one closest point, but only in clear cut cases.

• Find the Absolute Extremals of a Surface
  To find the extremal points/curves of a SISL surface in a given direction.

• Create and Compute the Bounding Box of a Surface
  To compute a box from the control polygon of the given SISL surface, in two or three dimensions.

• Create and Compute the Normal Cone of a Surface
  To compute the normal cone on the unit sphere to a SISL surface.