TYPE: SOP
TITLE: Bridge SOP

Given a set of profiles (i.e. curves on surface) and/or spatial faces, the
Bridge operation builds a NURBS skin with specified tangent and curvature
characteristics. The precision of the resulting surface is highly dependent
on the number of required cross-sections and on the quality of the profile
extraction. High precisions will generate a very dense surface with potentially
many multiple knots.

If no profile is entered in the group field, the operation assumes it must
bridge spatial faces. Examples of profiles include 0.5, 1.2-3.9, and 5.*.

Parameters:

    Group          - Subset of profiles and/or faces to bridge.
    Bridge         - Allows bridging of subgroups of N primitives 
                     or patterns of primitives.
    N              - Pattern of primitives to bridge.                  /inc
    Order          - Spline order for both profile extraction and skin /order

Surface Properties
    Min X-sections      - Minimum number of cross-sections in skin     /isodivs
    Use                 - Type of normal to use for computing direction
	Frenet Frame 	- This sets the local normal according the the
		  	  frenet frame of the curve.  This is the
			  vector perpendicular to both the tangent of
			  the curve and the binormal (the direction of
			  curvature)
	Normal		- This uses the calculated normal of the
			  entire curve as the normal.
    Circular-Arc Fillet - Build the skin as a circular fillet, if possible

    Rotate/Scale Tangents - The scaling and rotation parameters contain three 
			    fields:
	First Field	- Applies to the first face in the input.
	Second Field	- Applies to all intermediate faces.
	Third Field	- Applies to the last face in the input.

    Rotate Tangents     - Further rotation of the tangents (degrees)   /rotatet1
                                                                       /rotatet2
                                                                       /rotatet3
    Scale  Tangents     - Further scaling of the tangents.             /scalet1
                          When building a circular fillet only the     /scalet2
                          sign of the tangents is used                 /scalet3
    Use Curvature       - Take curvature into consideration as well
    Scale Curvatures    - Further scaling of the curvature             /scalec1
                                                                       /scalec2
                                                                       /scalec3

Profile Extraction
    Overview               - The parameters in this tab determine the
			     precision with which to extract profile curves.
    Divisions Per Span     - Number of 2D points evaluated in each span  /sdivs
    Tolerance              - Precision of 2D fitting algorithm       /tolerance
    Preserve Sharp Corners - Enables or disables fitting of sharp turns

See also: Fillet, Join, Stitch, Skin
