Curve Reconstruction Quick Help

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  Curve Reconstruction  
  This tool performs a filtering operation on the curves in the sketch and reconstructs them using various algorithms.  This tool is especially useful for reducing the number of control polygons and smoothing out existing curves.
 
 

Make Editable NURBS:  Convert the reconstructed curve into an Editable NURBS format and loose the history or previous construction information. 

Reverse Direction: If checked will reverse the orientation of the reconstructed curve.

Start Trim %:  The percentage distance along the curve to trim back
End Trim %:  The percentage distance from the end of the curve to trim back

  Reconstruction Algorithm to use  

None:  Don't use any reconstruction techniques.
Cardinal:  Fit a cardinal Spline through the points of the original curve.
Hermite:
  Fit a Hermite curve through the points of the original curve.
Re-Interpolate:  Re-interpolate the points of the original curve.
Re-Approximate:  Re-approximate the points of the original curve - this technique is used to reduce the number of control points and obtain a smoothest possible curve.

  End Point Continuity to Maintain  

The Re-Interpolate and Re-Approximate algorithms also allow you to constrain the ending continuity of the original curves.  The following options are available:

None:  Don't utilize existing curve continuities.
G1 Continuity: Match the 1st derivative direction of the original curve at both ends.
G2 Continuity: Match the 1st derivative direction and the curvature of the original curve at both ends.
G3 Continuity: Match the G2 Continuity and also the 3rd derivative at the curve ends.

  Parameterization  
 

These options are applicable when ther is a Re-Interpolation or Re-Approximation.  It controls how the knot vector is formed in the resulting curve.

Uniform: This option will produce a uniform knot vector in the resulting surface. 
Chord Length:  This option will change the parameterization to be proportional to the distance between the input shapes.  
Centripetal:  This option will change the parameterization to be proportional to the square root of the distance between the input shapes.

 
  Curve Reconstruction  

Num Samples:  How many points to take from original curve to be used in reconstruction.  
Tension:  Tension to apply if Cardinal spline is created.
Adaptive Sample:  If TRUE then use adaptive sampling tessellation with below specified tolerances instead of a uniform "Num Samples:"
Angle Tol:  Maximum angle allowed between three successive points in tessellation of original curve.
Chord Height%:  Maximum chord height between the arc and the approximating lines.  This defines the distance of how the tessellation approximates the original.

  Least Squares Fit  

# Control Points:  Number of control points in the Re-Approximated curve.
Degree:  Degree of the Re-Approximated curve.