Advanced Surface Options

The Advanced Surface Options tab of the Curve and Surface Fitting dialog box allows you to set how the surface internals are created.

Advanced surface options are only used when you are creating surfaces; they are not used in the creation of curves. It is divided into two areas.

In the Internal Smoothing area, you can select whether the surface tangents and magnitudes, or surface points are freed to produce smoother and better quality surfaces:

• No surface smoothing
  
  
• Smooth surface internals – select this option to allow the tangent and magnitude of each point to be modified to ensure a smoother match with surrounding surface internals, when those internals are not on a surface boundary. This smoothes the middle of the surface but does not allow smoothing at the surface boundaries.
  
  
• Smooth whole surface – select this option to allow the tangent and magnitude of each point to be modified to provide a smooth surface that matches the tangents and magnitudes of surrounding internals.

CopyCAD however will not modify tangents/magnitudes that are on surface boundaries where tangency has been specified when the surface boundary was created, as this would disturb the continuity of tangency between surfaces.

• Smooth whole surface (including single patch surfaces) – select this option to allow the tangents and magnitudes of each point in a surface to move, even if the surface is one patch wide, whilst maintaining tangency. Single patch surfaces (internals are from sides 1 to 3 only, or 2 to 4 only) are smoothed to create flat surfaces.
  
  
• Maximum smooth of whole surface – select this option to allow each point (not just its tangent and magnitude) to move up to half the specified Curve Fitting Tolerance.

In the Internal Fitting area you can set the following options:

• Internal Skew (0 – 100%) – this controls the maximum amount of "skew" allowed between the internals of a surface in relation to the surface boundaries. 0% skew is when the internals are parallel to the surface boundaries.
  
  
• Allow Discontinuities in Internals - When turned on, this allows CopyCAD to put a discontinuity in the internals.

When turned off, this ensures that there is tangent continuity in the internals

• Internals Follow Boundary Shape – This option gives a simple parameterisation of the surface and is useful when you have unmatched boundaries. When turned on, this forces the internals to follow the boundary shape.

When turned on, the internals follow a direct path from one side to the other.

Note: There must be internals in both directions for this option to have any effect.

• Internal Fitting Tolerance – sets the tolerance used for the surface to fit to the model.

More:

Using the Curve and Surface Fitting Options