Creo Model Edge Display Quality

[ptc-1375004]

I am aware that default accuracy settings changed from Creo 6 to 7 (& 8).  But whether or not these changes affected edge display quality is both unclear and without a way to fix it.

Note in the attached images that a "Medium" edge display quality on a 1.5" diameter cylinder is acceptably smooth in Creo 6 whereas the "Medium" edge display quality for the same part in Creo 8 is unacceptable.  Of course, there is the option of "Very High" in Creo 7 & 8 also result in unacceptable edges.

If this issue is related to the changes in "accuracy" that occurred in the changes from Creo 6 to 7 & 8, can someone please provide an explanation of how to address this?

[MartinHanak]

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@ptc-1375004 wrote:

I am aware that default accuracy settings changed from Creo 6 to 7 (& 8).  But whether or not these changes affected edge display quality is both unclear and without a way to fix it.

Note in the attached images that a "Medium" edge display quality on a 1.5" diameter cylinder is acceptably smooth in Creo 6 whereas the "Medium" edge display quality for the same part in Creo 8 is unacceptable.  Of course, there is the option of "Very High" in Creo 7 & 8 also result in unacceptable edges.

If this issue is related to the changes in "accuracy" that occurred in the changes from Creo 6 to 7 & 8, can someone please provide an explanation of how to address this?

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Hi,

please upload pictures, template models (Creo 6.0 + Creo 7.0) and  user models (Creo 6.0 + Creo 7.0).

[ptc-1375004 · Accepted solution]

Sorry, for some reason the uploads were lost on my post.  So, I have attached them again.

In the meantime, I discovered a way (perhaps, the preferred way) to fix this, within the Model Properties panel.  Under "Model Properties", "Accuracy", is a change option for either Relative or Absolute accuracy.  Note in attached images for this 1.5-inch-diameter part, the edge facets when relative accuracy is 0.01 versus 0.001:  visible curved edge facets to a smooth displayed edge curve.

Of course, as one can set the Absolute Accuracy, accuracy_lower_bound parameter, in the config.pro to some value; in my case to 0.000001 or 1.0e-6, then the display edges are visually crisp.  Note also, that the enable_absolute_accuracy parameter (which was used in Creo 6) and left over from my previous config.pro file, is no longer recognized in Creo 7 or 8.

The available PTC documents on the topic of accuracy, IMO are hopelessly incomplete and obsolete.  I gather that PTC implemented these changes to how accuracy was handled due to performance issues with large models.  So, if the need arises the current method of changing accuracy on an individual part basis could be advantageous.