On Mon, Nov 25, 2024, 5:01 AM Liang Jia <lantianjiali...@gmail.com> wrote:
> Hi Mark, > > Thanks for your email. > > Could you please explain more about the relation between "Change the > measurement store from 32-bit to *64-bit*" and "128-bit integer math > support in processors"? > And why did Kicad choose integer as internal measurement resolution? > Because we need exact locations of elements. Floating point is very accurate for small numbers (close to the origin) and very inaccurate for large numbers (far from the origin). So, for the larger boards, you end up with clearance errors and possible manufacturing issues at the edges. > > Last, so that means there is no way to handle this issue? > Addressing this means reworking our internal coordinate system. Either figuring out how to work efficiently with larger integers (so that it doesn't slow down work on normal sized boards) or changing to a dual integer+fractional fixed point representation. Either way requires a lot of internal work as Mark mentioned. Seth > On Mon, 25 Nov 2024 at 19:21, Mark Roszko <mark.ros...@gmail.com> wrote: > >> >This means it is possible to create boards up to approximately 4 meters >> by 4 meters >> >> Yes, KiCad is limited to 4x4 meter boards currently. >> >> > Change the measurement store from 32-bit to 64-bit, so Kicad can >> support a larger board. >> >> This is not an easy task in the slightest. Specifically because we can't >> get 128-bit integer math support in processors, and many compilers do not >> support 128-bit integers. I think gcc has some experimental support. >> >> > Change the resolution of all objects to mm >> >> mm is not adequate to express the resolution of position data required >> for a board design. >> >> >> >> Basically the bug here is we simply do not tell the users the DXF is >> beyond our board support limit. >> >> >> On Mon, Nov 25, 2024 at 5:07 AM Liang Jia <lantianjiali...@gmail.com> >> wrote: >> >>> Hi All, >>> >>> I am writing to inquire about the challenges we are facing when >>> importing DXF files which contain large numbers into our system. >>> >>> I have noticed that when the number exceeds a certain threshold(such as >>> 4437 mm), the import process results in an int overflow error. >>> >>> I did the search below: >>> 1. Found that there was a ticket to track it, but it seems *it still >>> opens*. >>> https://gitlab.com/kicad/code/kicad/-/issues/12392 >>> >>> 2. From the Kicad document: >>> The internal measurement resolution of all objects in KiCad is *1 >>> nanometer*, and measurements are stored as *32-bit integers*. This >>> means it is possible to create boards up to approximately 4 meters by 4 >>> meters >>> I think the *root cause* is here: Kicad tried to convert the DXF number >>> into nanometer, but those numbers exceeded the limit of integer. >>> >>> Questions: >>> 1. Is there any workaround for this case, and let Kicad import those >>> files successfully? >>> 2. If I want to fix ticket 12392, what should I do? >>> Change the measurement store from 32-bit to 64-bit, so Kicad can >>> support a larger board. >>> Change the resolution of all objects to mm >>> >>> Looking forward to any comment or workaround. >>> >>> Sincerely >>> Liang >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "KiCad Developers" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to devlist+unsubscr...@kicad.org. >>> To view this discussion visit >>> https://groups.google.com/a/kicad.org/d/msgid/devlist/CAE0Ak8bd%3DgDwW%3DDWVXH-TKj%3Dr4nsgW370aNqB6PbP7T8b2QU6A%40mail.gmail.com >>> <https://groups.google.com/a/kicad.org/d/msgid/devlist/CAE0Ak8bd%3DgDwW%3DDWVXH-TKj%3Dr4nsgW370aNqB6PbP7T8b2QU6A%40mail.gmail.com?utm_medium=email&utm_source=footer> >>> . >>> >> -- >> You received this message because you are subscribed to the Google Groups >> "KiCad Developers" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to devlist+unsubscr...@kicad.org. >> To view this discussion visit >> https://groups.google.com/a/kicad.org/d/msgid/devlist/CAJjB1qKoN689BoyB1uWpWYmDCpbaCRKCyW2qmnBOoG5Au_Nnfg%40mail.gmail.com >> <https://groups.google.com/a/kicad.org/d/msgid/devlist/CAJjB1qKoN689BoyB1uWpWYmDCpbaCRKCyW2qmnBOoG5Au_Nnfg%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> > -- > You received this message because you are subscribed to the Google Groups > "KiCad Developers" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to devlist+unsubscr...@kicad.org. > To view this discussion visit > https://groups.google.com/a/kicad.org/d/msgid/devlist/CAE0Ak8bmAyB7ciCe6nrps8gw0meXgaj25r5Zq-o2Z9x_-8CFDA%40mail.gmail.com > <https://groups.google.com/a/kicad.org/d/msgid/devlist/CAE0Ak8bmAyB7ciCe6nrps8gw0meXgaj25r5Zq-o2Z9x_-8CFDA%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "KiCad Developers" group. 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