Squaring-Error

[hajo4]

"Square an area" should align the corners of an area / building,
to beautify it to a more right-angled shape.
But sometimes this does not work right, and ends up with an unuseble shape,
e.g. one corner is lost (or 2 points moved to the same coordinates).

When mapping small villages, there are quite a lot of old buildings with odd shapes.
This is where I encounter the buggy behaviour of "square an area" more frequently,
but it can happen with simple 4-cornerd houses too.
(I just didn't bother to write a bugreport yet)

Here some examples from the village Rossdorf/Zeilhard :

• Way/316791604 - simple house
• Way/316801542 - 8-corner house gets distorted
• Way/316794583 - another big building with "indent".
• Way/316873578 - some kind of storage building
• Way/316794582 - Farm-building
• Way/320705754

Find all those places I marked with notes: http://overpass-turbo.eu/s/6tN

Note: since the report, there has been an automatic mass-edit,
that might have corrected the data that leads to the error,
see http://www.openstreetmap.org/changeset/27512311

[bhousel]

Way/316801542 - 8-corner house gets distorted

yep:

[bryceco]

In Go Map!! I'm using the iD code for squaring, translated line-for-line to C. The first way (Way/316791604) fails because it contains a duplicated node that produces a NaN. The other examples work perfectly for me, with none of the distortions iD has, so it doesn't seem to be a fundamental algorithm bug.

[rivermont]

I'm assuming this has been fixed @bhousel ?

[bhousel]

I'm assuming this has been fixed @bhousel ?

I don't think anything has changed on this.