Why are Torus features so slow in NX? 2

[CNSZU]

Hello everyone,

Why is it that revolved toruses/rings are so much slower to create and regenerate than than other features?

The attached image shows two versions of a feature pattern, the first is a revolved cube, the other a revolved circle. While the first one takes a blink of the eye to regenerate, the circle version needs 35 seconds! And if you suppress and unsupress, it will take 1 minute and 45 seconds to display the torus pattern!

In assemblies this causes another problem that if a component consists of a pattern of toruses, it dramatically slows down assembly operations, like adding assembly constraints and modifying those constraints.

Out of curiosity I created the exact same part in Solidworks, it regenerated instantly, and suppressing and unsupressing took about 2 seconds. So obviously this is a problem exclusively in NX and nothing to do with the kernel.

My machine specs are not inadequate and I have no problems with other types of features. Torus features is a major problem, what can be done to speed them up?

NX8 E8800@3.7Ghz 6GB Quadro2000

 

[uwam2ie]

hi,
the new pattern feature can handle this,but I would use Instance Geometry in this case,( individual bodys ), give it a try.

 

[CNSZU]

I tried using Instance Geometry, the time it took to regenerate was 42 seconds...

It's not the pattern that is the issue, the pattern only exaggerates the problem, the problem is the way NX creates the revolved torus feature.

NX8 E8800@3.7Ghz 6GB Quadro2000

 

[CNSZU]

I discovered how to fix the problem, I had the faceting of shaded views set to Ultra Fine, changing this setting to Extra Fine improves the rendering speed quite a lot. This setting is in Preferences>Visualization>Faceting.

Anyhow, isn't this related to the graphics card? Isn't Quadro 2000 enough to handle Ultra Fine faceting?

NX8 E8800@3.7Ghz 6GB Quadro2000

 

[JohnRBaker]

Anyone who by default uses anything other than 'Standard' resolution for their Visualization Faceting settings is only wasting their time, literally! Unless you have some compelling need, you're only wasting your time if you set your default to 'Extra Fine' or even 'Fine'.

Granted, when doing high-quality rendering using the graphics hardware such as in Studio mode, you may wish to use a higher resolution. This is why we've provided different settings, Shaded Views versus Advanced Visualization Views. So set these accordingly.

Of course, the reason that you noticed this with the torus is because the shape of a tori is one the most complex that there is when it comes to creating facets.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

UG/NX Museum:

http://www.plmworld.org/p/cm/ld/fid=209

To an Engineer, the glass is twice as big as it needs to be.

 

[Toost]

Try this to see why it takes time.:
Preferences - Visualization - Faceting, In the bottom there is an option "Show facet edges", turn that on and then try the different resolutions. Maybe you need to regenerate the graphics after changing the resolution, View - Operation- Regenerate Work.

And btw, ;-) what resolution was Solid Works using ?

Regards,
Tomas

 

[CNSZU]

Toost, I tried that and yes, that function clearly shows how the faceting of the model changes when changing the view settings, thank you for that tip.

As for Solidworks, I cranked the "Image quality" up to full, with a deviation of 0.0462. But the torus still regenerates without the slightest delay, even when zooming up very close. The same torus will regenerate much, much faster in Solidworks than in NX. Maybe the reasons are:

-Solidworks uses a clever algorithm.
-NX doesn't fully utilize the graphics card.

Another problem is the issue of faceted curves. In NX, the faceting of curves is related to the resolution of shaded views. But in Solidworks, all curves are display super smooth regardsless of the faceting of shaded objects. See attached images.

http://files.engineering.com/getfil...c42-a8b6-9a7bbd7dbd78&file=nx_tesselation.PNG

http://files.engineering.com/getfil...28f-b029-c7145927957d&file=sw_tesselation.PNG

I can tolerate low faceting of shaded objects, but I cannot tolerate jagged curves. Is there a way to improve the display of curves in NX without compromising the performance?

NX8 E8800@3.7Ghz 6GB Quadro2000

 

[JohnRBaker]

Are we talking about the 'edges' of a solid face or are we talking about 'curves'? The 'edge' of a solid is NOT a 'curve', at least not in terms of what's controlling the smoothness of it's display. In other words, the display of the 'edges' of a solid is based on the resolution set for 'Shaded Views'. Curves are just that Curves or when a solid is being displayed using the Rendering Stype 'Static Wireframe' (NOT 'Wireframe with Hidden Edges' BUT 'Static Wireframe'). To set the display resolution of 'curves', go to...

Preferences -> Visualization -> Line

...and set the value labeled 'Curve Tolerance'.

Now there are some other things that needs to be considered. When working with an assembly, be careful since by default (starting with NX 7.5) the display of solid/sheet models are being done using Lightweight (faceted) representations so no matter WHAT resolution that you chose for displaying 'Shaded Views' or the 'Curve Tolerance', it will have no effect whatsoever. These only apply when working in a piece part or in the Work Part when working in context of an Assembly or if the Assembly was loaded using Exact representations.

And if you zoom in on a model which is not faceted and you see 'faceted' edges/curves, simply hit the 'Update Display' button.

And there is one more thing that you can do if you're really looking for the best possible display of whatever and that is toggling ON the 'Curve Antialiasing' option found on the...

Preferences -> Visualization -> Visual

...dialog in the section labeled 'General Display Settings'.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

UG/NX Museum:

http://www.plmworld.org/p/cm/ld/fid=209

To an Engineer, the glass is twice as big as it needs to be.

 

[CNSZU]

Thank you, John, the "curve tolerance" solved the problem, it was set to 0.005. When changing this to 0.0001, the curve looks smooth at all zoom levels without having to update the screen.

However, there is one issue remaining, and that is in the case where you have the shade faceting set to "Standard", then when you zoom in close to the torus, the torus will appear faceted. Now when using the "Update Display", it took 32 seconds to display the torus. In Solidworks, the torus looks smooth no matter how close you zoom in, and you don't have to do anything special to update the display, and it regenerates instantly. For the moment, in NX, I'm getting around this by setting the faceting to "Extra Fine", this way the torus will still look acceptable when zooming in close and I never have to use the "Update Display" button.

NX8 E8800@3.7Ghz 6GB Quadro2000

 

[JohnRBaker]

And WHY are you so bloody torqued over the display tolerance? And by the way, the reason the torus LOOKS like it's faceted IS BECAUSE IT IS FACETED!!!!!! Learn to live with, the rest of us have.

Anyone who sets tolerances and resolutions as high as you're doing has NO right to complain about performance. We have porvided you the tools and options to get the best performance possible. If you don't take advantage of them after being told what to do, you're just wasting mine and everyone else's time answering your questions. You've obviously come here with an agenda. If your intentions are to look for and then bitch about one thing after another, please go away. The Eng-Tips Forum was not established for this sort of activity.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

UG/NX Museum:

http://www.plmworld.org/p/cm/ld/fid=209

To an Engineer, the glass is twice as big as it needs to be.

 

[Xwheelguy]

Gotta give a star for that one! Was beginning to think this was the Solidworks comparison forum now.

Tim Flater
NX Designer