Arc Tolerance

Currently is causes failure of the MK buildbot regression tests.

Once I have figured out how those tests need changing and it is fully tested will port across for 2.7 too

regards

Now sorted the runtests issue for MK and all works.

The default arc tolerance is set to the figures you suggested, which equate to
TOLERANCE_INCH 0.0028
TOLERANCE_MM 0.0282

The minimum has been set to
MIN_TOLERANCE_INCH 0.00004
MIN_TOLERANCE_MM 0.001

which is 1 micron and imperial equivalent +/-
Attempting to go down to 0 will produce errors such as abs_err = 2.2e-16 rel_err = 0.0000% .

1 micron is probably fine enough!

Patch submitted direct also

regards

@ArcEye
@seb_kuzminski

Please explain to a German, why the arc tolerance for metric and imperial units are different on default.
IMHO it makes no sense to set the metric tolerance wider than the imperial by default.

1 inch = 25,4 mm

so the default imperial tolerance of 0,0028 results in 0,071 for metric. not 0,0282

I would suggest to set a arc tolerance lower than 0,05 mm as default, the suggested 0,0282 mm seems ok, but than imperial should be 0,00111 inch.

Norbert

Please explain to a German, why the arc tolerance for metric and imperial units are different on default.
IMHO it makes no sense to set the metric tolerance wider than the imperial by default.

Hi

Because that is what the developers wanted. I originally set the metric (which I use, I am in the UK) to the same tolerance as the imperial, in the original simple fix of the values.

Seb wrote:

1. The default tolerance (if none is specified in the ini file) should be 2 * 0.001 * sqrt(2) for inch, and 2 * 0.01 * sqrt(2) for mm. This would mean that any valid arc where the endpoints and/or centerpoint got rounded or truncated to 0.001 inch or 0.01 mm precision would be accepted

The rationale I think was to cater for the rounding up of values by CAM programs, the value at which each gets rounded up differs, because of the base is different for both.

I'll let Seb confirm that.

regards

PS I have set the minimum value the same for both metric and imperial, yet to see if that gets through

Thanks for setting them to the same values.
All other stuff makes no sense!

Norbert

ArcEye wrote: Now sorted the runtests issue for MK and all works.

The default arc tolerance is set to the figures you suggested, which equate to
TOLERANCE_INCH 0.0028
TOLERANCE_MM 0.0282

The minimum has been set to
MIN_TOLERANCE_INCH 0.00004
MIN_TOLERANCE_MM 0.001

which is 1 micron and imperial equivalent +/-
Attempting to go down to 0 will produce errors such as abs_err = 2.2e-16 rel_err = 0.0000% .

1 micron is probably fine enough!

Patch submitted direct also

regards

I don't understand the rational of setting the default to different values and the min to the same value. Seems to me if 0.002" is good then mm should be 0.05, or the other way around if 0.25mm is good then inch should be .001" Maybe I just don't understand the logic of the default setting.

JT