Re: [Emc-developers] When is an arc small?

2022-02-05 Thread andy pugh
On Fri, 4 Feb 2022 at 21:27, andy pugh wrote: > (Incidentally, part of the reason that the preview and motion differ > is because motion is in metric and preview is in imperial! At least > with a metric config and metric G-code. I will need to test the 4 > combinations) More digging I

Re: [Emc-developers] When is an arc small?

2022-02-05 Thread andy pugh
On Sat, 5 Feb 2022 at 12:14, Stuart Stevenson wrote: > I haven't calculated how far the midpoint of the arc is from the midpoint > of a straight line from point to point using the values in your example but > I know it would not be much. In this case, 0.4 nm. Or 2.5 aluminium atoms. Replacing

Re: [Emc-developers] When is an arc small?

2022-02-05 Thread Stuart Stevenson
Andy, I haven't calculated how far the midpoint of the arc is from the midpoint of a straight line from point to point using the values in your example but I know it would not be much. I do know APT uses 2500 inches as the cutoff point for radius calculation. I don't know the exact reason for

[Emc-developers] When is an arc small?

2022-02-04 Thread andy pugh
LinuxCNC G-code assumes that the programmer wanted a full circle if the coordinates of the start and end points in the plane are "the same". Currently both the preview interpreter and motion use the angle between the start and end points of an arc to decide if the start and end coordinates are