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Relatrive/Absolute ?


New member
Can somebody pleaseeeee tell me the difference between Relative & Absolute accurcy? & How it works, Please I need it in detail.

I was working one comp which has got more that 200 instances & length of all those is smaller than the Generic, few instances were running ok & few were failing (say 50%) then I changed the accuracy of it to Absolute & is working fine, I wanted to kow WHY ?



New member
Accuracy refers to the smallest curve lengths Pro is capable of seeing when calculating geometry. Pro puts your model in a rectangular box just large enough to encompass it. By default, the accuracy is 0.0012 times the cross-diagonal length of that bounding box. You can lower the relative accuracy to 0.0001.

If your models are relatively big compared to your smallest curve lengths, especially when doing surface operations like creating normal offset surfaces, or those small curves are the parents of other features, your model can fail.

It sounds like you were using absolute accuracy-- specifying a numerical value for that smallest curve length-- that was larger than what Pro could see. By changing to absolute (and I assume using the default of 0.0012), now Pro could see and calculate geometry based off those small curves.

Dave Martin


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