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Re: PCBNEW NANOMETRES build zoom crash

 

On 4/18/2012 3:48 PM, jean-pierre charras wrote:
Le 18/04/2012 20:25, Dick Hollenbeck a écrit :

I am working on this today.

My gut says this:


Basically it comes down to the fact that we cannot describe an area
larger than about 12
feet with the nanometer internal units.


Jean-Pierre,

Can you first look over the attached patch, then play with it.

This basically fixes the crash, but I think there's more finishing
touches that need to be
done.

I need to get back to work now.


Thank you very much,

Dick

I'll work on that tomorrow.

I also make some tests.
Under Windows I did now have crashes, but I had other issues.

Make sure you're not getting bit by this bug http://trac.wxwidgets.org/ticket/10446 again. I don't know if this problem has ever been fixed or even if it still exists on Window's Vista and/or 7.


my opinion is with 32 bits integers we cannot handle more than something
like 50 to 70 cm,
with nanometers units.

I noticed there are a lot of issues when calculating distance between 2
points.

Assuming calculations are using integers, with 32 bits we can handle 2
meters distances only.
if Xmax and Ymax are Y and Y difference between 2 points,
only Y or Y max <= 1.4 meter, if sqrt( Xmax*Xmax + Ymax*Ymax) always < 2m.

Because a distance is always >= 0, this means X and Y coordinates must
have absolute coordinates < 70 cm.
With margins around work area, and because Pcbnew and Gerbview use a
page only with positive coordinates,
the active area has a size < 50cm, roughly 20 inches, or A3 or B page size.






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