Fixed extra z-hops in Surface slicing mode

[IkonOne]

closes #1532

Open poly lines were never cleaned up the same way that polygons are.

[IkonOne]

Before

After

Example project (zipped up 3mf).
surface_mode_closed_polygons.zip

[rburema]

Hi! It's such a small and sensible change, let's see if it can be in the next version.

Devs: Created internal ticket CURA-8745 to track this.

[IkonOne]

That would be great! I really thought I was going to have to get fancy but as I was going through the code I thought well I have to try that and here we are.

By the way, does Ultimaker ever open up internships that might be accessible to an American? I would love to work on a product like Cura regularly.

[Ghostkeeper]

Ultimaker does have an American office but it's not doing R&D (which includes Cura). As far as I know, Ultimaker asks all employees and interns for R&D to be able to be able to go to the office in the Netherlands somewhat regularly (at least if CoViD lockdowns weren't in force) and that'd require you to come to the Netherlands. Your best bet would be to find an exchange program I guess.