Details
Regenerate Functions Differently in NX9 and LaterVersus Earlier NX Releases.
Solution
When working with shaded displays in Modeling Application NX added display
facet caching in NX9.
Prior to NX9, when a regeneration request for a solid was made, NX had to
tessellate the solid, which could be very time intensive.
Starting in NX9 when a regeneration request is done on a solid, and NX has
available and up to date facets in the facet cache, NX uses those (no
tessellation occurs). This introduces significant time savings on a
regeneration in general. The other thing NX now does is change the default
facet scaling factor from view-based to part-based scaling. This last change
can have a noticeable impact when zoomed in significantly on a model (besides
the faster aspect, it can be a little cruder than view-based scaling,
especially as you zoom in). The main reason this was changed to the
facet-scaling factor is that it allows facets to be reused much more often.
One consequence of changing facet scaling was that it became noticeable that
NX did not always explicitly specify a chordal angular tolerance when
generating facets - this was a holdover from earlier option specifications for
using the Parasolid tessellated for NX display. View-based facet scaling hid
the fact that not specifying the angular tolerance could result in poor
looking circles (for example holes) in general. When a part is fit in the view,
the view scale and the part box scale are similar (usually) so the results are
generally the same there, so it is also generally not as noticeable there.
NX12 will always attempt to specify an explicit chordal angular tolerance -
this improves display quality in general, especially around curved edges.
When introducing facet caching, we decided to leave Update Display as a
means to quickly improve the facet quality, as though View-based
facet scaling was in effect, without the need to go to a dialog that exposes
facet settings. However, those changes are generally transient, in that if a
subsequent regeneration is made, we opt for the settings in effect (which
generally results in fewer facets when part-based facet scaling is in effect).
NX should now use the most precise set of facets that NX has available,
(if a complete set is available at that precision), on subsequent regeneration
requests (also in NX12).
Notes and References
Hardware/Software Configuration
Platform: INTEL
OS: window
OS Version: 764SP1
Product: NX
Application: SYSENG
Version: V11.0.1
Function: DISPLAY
Ref: 001-9198248