Yep! The post-import work of setting the degree to the desired 45 is what I was speaking to. I definitely agree - and wasn't speaking to the amount of work (as its not much) - but rather was commenting on the fact that there is work (when you don't need it). Anytime a user is required to do something, it just adds another step where there can be a user mistake (e.g. typing '46' on accident or just forgetting to do this step - I've unfortunately seen a lot of this).
This is typically not so much an issue with the angle as you mentioned since its more obvious on screen if its wrong and also how you would adjust per the drawing layout needs, but I've run into it a lot with hatches being scaled. Someone scales the 4x8 and now its actually 6x12 but still labeled wrong - and when some other team wants the 6x12 its not easily exported or transferred between office projects. It also happens a lot for someone changing material density for drawing scale slightly and now material density not matching across the drawing set.
Unfortunately, I can't speak to your concerns about drift with a standard pattern file like herringbone. The files provided were to 8 decimal places, and when I tested 5,000 feet from the PAT origin, there was absolutely no 'drift' at all.
Maybe you are thinking of user drafted patterns that get converted in programs from say DWG to PAT files? Some programs unfortunately don't convert properly and wont auto-adjust for angle dimensional tolerances that the PAT math requires. In these outputs there can be very bad drift depending on the pattern (and quality of program).
Thanks for the thoughts though, our standard was to test all Pattycake generated patterns to a fidelity of 500 feet origin tolerance, but i'll bump this up to 5,000 and keep an extra close eye on it.
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