Re: gEDA-user: pcb crooked traces

[Steven Michalske <smichalske@xxxxxxxxx>]

Internally the origin of the grid should go to the middle of the
board, but have the board translate the coords to physical of the
upper left, or even lower left.  Make some folks happy about their y
decreasing or somthing or another.

This removes the loss from the other three quadrents of area and gives
us 4.29 meter boards.  Using a signed number and just using the 1st
quadrent is a waste, of about 2 meters.  ;-)  normally the folks won't
need to set the origin other than the upper left of the board,  but
for those 4 meter boards you'll have it.  and HUGE boards sets it to
64 bit integers.....

For those large or miniscule boards a nice scale setting solves any scale issue.

Steve

On Tue, Oct 12, 2010 at 11:44 PM, Rick Collins <gnuarm.2006@xxxxxxxxx> wrote:
> At 11:26 AM 10/12/2010, you wrote:
>
>> But if we limited everything to 2m, using unsigned integers, we'd
>> be okay with 32 bits. I'm not sure what you're saying here.
>>
>> Having said that, I still want negative coordinates. So do we need
>> to limit things to 1m? Yuck.
>
> He is saying that to avoid overflow in internal calculations, you could have
> parts up to 1 meter on a board up to 1 meter with the part placed at the
> upper edge of the board putting the upper edge of the part at 2 meters.
>
>
>> Well, ``probably slower'' isn't a good reason for anything. I doubt
>> your speculation on both 32- and 64-bit machines, so testing will
>> need to be done.
>
> WHOA!!!  We should actually measure how much the application would slow
> rather than speculate or use pointless metrics such as how fast a test
> program doing nothing but a math operation runs...  what a concept!!!
>
> So who is going to bell the cat?
>
> Another thought.  Using 1 nm as the base unit does everything anyone wants,
> but limits the max size board on 32 bit machines.  But do we really need 1
> nm resolution?  This allows exact representation in nm of 0.01 mil in
> inches.  Do we need exact representation of 0.01 mil?  Would 0.1 mil be
> adequate?  Using 10 nm as the base unit internally gives exact
> representation down to 0.1 mil and allows much finer resolution, just not
> exact representation in inches.  With a 10 nm base unit the max board size
> goes to 20 meters which certainly is enough for everyone, including those
> wishing to design kitchens!
>
> Durn metric system!  Why can't our system be good enough for the rest of the
> world? :-\
>
> Rick
>
>
> _______________________________________________
> geda-user mailing list
> geda-user@xxxxxxxxxxxxxx
> http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
>


_______________________________________________
geda-user mailing list
geda-user@xxxxxxxxxxxxxx
http://www.seul.org/cgi-bin/mailman/listinfo/geda-user