Normal Surface Options

The Surfaces options panel controls how Regina works with lists of normal surfaces.

The settings here are:

Default coordinate system

Specifies which coordinate system will be the default when you enumerate normal surfaces.

Default top-level tab

Specifies which tab in the surface list viewer will first appear when you open a normal surface list for viewing.

Default compatibility matrix

Specifies which matrix (local or global) will first appear when you switch to the surface compatibility tab.

Compatibility matrix threshold

Determines when the surface compatibility matrices will be computed. If the number of normal surfaces is at most the given value, then Regina will compute compatibility matrices automatically. If the number of surfaces is larger, then Regina will not compute these matrices until you manually press the Calculate button.

Warn before generating non-embedded surfaces

If checked, Regina will ask for confirmation whenever you try to enumerate normal surfaces without selecting embedded surfaces only. Regina asks for confirmation because non-embedded surfaces are typically much slower to generate, far more numerous, and Regina only offers very basic support for them.

Support transversely oriented normal surfaces

As of version 4.92, Regina offers support for transversely oriented normal surfaces [CT09]. However, this feature is highly experimental and still a work in progress, and things will break if you use it. Because of this, transversely oriented coordinate systems are hidden from users by default.

If you check this box, Regina will offer traversely oriented coordinate systems for creating and viewing normal surfaces. Once again, this is a work in progress, and you should not trust any results in these coordinate systems.

Once this feature becomes stable in a later version of Regina, transversely oriented normal surfaces will be supported by default (and this option will be removed).