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Date: Tue, 1 Dec 2015 13:48:43 +0100
From: Martin Beranek <martin AT mb5 DOT cz>
To: geda-user AT delorie DOT com
Subject: [geda-user] PCB: clearouts in polygons slightly off, fix?
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Hi all,

I have noticed that the code cutting holes/clearance into polygons
around traces and pads (that is code in polygon.c) creates contours
which are a little off.

For example long straight edges of the clearout around square pad are
not exactly parallel with the pad edges because round corners are
generated without last vertex. There is few similar issues in the code.
(You can see this, without reading the code, by zooming in to the edge
of the small pad's clearout, preferably with the finest grid setting).

I am considering to fix it, at least for my personal use, but I guess it
should be fixed in the project too. But ... fixing this issue causes
existing PCB files to be rendered slightly different (more correct in
fact, but, nonetheless, different compared to the current situation).
The differences are minor, but existing and one can imagine that there
is chance that they can trigger new DRC error for example.

What is the project's opinion on this? Do you want the fix? Should one
worry about backward compatibility in this case? If so, then how?

Martin