DRC Acute angle check is implemented incorrectly. It gives junk results.

[warren_hawkins57R37]

DRC Acute angle check is implemented incorrectly. It gives junk results. An acute angle is an angle that is greater than zero and less than 90. The acute check includes any angle that is not 45 or 90. I getting errors for all angles greater than 90 which is not useful. Also getting errors for angles that are covered by PADs, vias, or copper pours etc. are not useful.

[jorge_garcia]

Hi @warren_hawkins57R37 ,

I hope you're doing well. The acute angle check can be disabled if it is not desirable. It will basically flag any angle that is not a multiple of 45 degrees. Imagine a trace that goes straight north south (90 degrees) a 130 degree traces off of it would still be acute when you have a fixed angle reference (3 o'clock is 0 in Fusion Electronics). The goal of the acute angle check is to avoid acid traps where you can get over-etching.  Modern manufacturing process have mitigated this a lot but at higher volumes you can still this costing boards.

Let me know if there's anything else I can do for you.

Best Regards,

[warren_hawkins57R37]

Hi Jorge,

Yes please have them fix it to work correctly. Turning it off isn't helpful if I want to detect actual acute angles for the reason you specified. But only detecting the actual definition of an acute angle would be a good start not something made up by someone without an understanding of the dictionary definition of the word or the reason we check for them. With it turned on I have thousands of false errors. Not useful at all.

Thanks,

Warren

[warren_hawkins57R37]

I should add that my angles are slightly off due to rounding errors from rotating the board. Would be nice if that got fixed too.

[jorge_garcia]

Hi Warren,

I think we are not understanding each other. I'm actually arguing that the current behavior is correct. Do you have a picture of the board where you are seeing the acute errors? That way we can talk in substance.

Let me know if there's anything else I can do for you.

Best Regards,

[warren_hawkins57R37]

I have over 4500 acute angle errors. So I can supply lots of examples. Many are hidden by other copper features so should be ignored by the error checker. However, many are not acute angles at all. Some are barely acute angles and only are due to glitches in fusion from rotations moving things etc. It would be good to have a tolerance for acute angles. I probably don't care if it's 89 degrees due to math errors from operations that cause drift.