#20 Undesired zero width bridge when performing difference operation

[Anonymous]

This is a very useful library for a project I'm prototyping, but I saw some unexpected behavior while attempting to perform a difference operation. I included an image of the paths, including the desired and actual results.

Start with an L-shape:

[[{"X":96,"Y":32},{"X":128,"Y":32},{"X":128,"Y":96},{"X":32,"Y":96},{"X":32,"Y":64},{"X":96,"Y":64}]]

Attempt to cut this box away:

[[{"X":128,"Y":96},{"X":64,"Y":96},{"X":64,"Y":64},{"X":128,"Y":64}]]

End up with this, which has a width 0 bridge connecting two squares:

[[{"X":128,"Y":64},{"X":64,"Y":64},{"X":64,"Y":96},{"X":32,"Y":96},{"X":32,"Y":64},{"X":96,"Y":64},{"X":96,"Y":32},{"X":128,"Y":32}]]

What I would expect is just the two squares:

[[{"X":128,"Y":32},{"X":128,"Y":64},{"X":96,"Y":64},{"X":96,"Y":32}],[{"X":64,"Y":96},{"X":32,"Y":96},{"X":32,"Y":64},{"X":64,"Y":64}]]

If I perform a similar operation rotated 180 degrees I see the same undesired bridge, but this is not the case for if the paths are rotated 90 or 270 degrees.

[Timo Kähkönen]

Hi, Thanks for reporting. This issue is true in 6.2.1.2. The upcoming 6.4.2.1 fixes this problem.

6.2.1.2:
[[{"X":128,"Y":64},{"X":64,"Y":64},{"X":64,"Y":96},{"X":32,"Y":96},{"X":32,"Y":64},{"X":96,"Y":64},{"X":96,"Y":32},{"X":128,"Y":32}]]

6.4.2.1:
[[{"X":128,"Y":32},{"X":128,"Y":64},{"X":96,"Y":64},{"X":96,"Y":32}]]