[BUG] Arrange modes "Balanced" and "Accurate" fail to arrange instances with sufficien margin to avoid extruder collision

[staspika]

Description of the bug

When selecting "Complete individual objects" and pressing "Arrange" while geometry handling "Balanced" or "Accurate" is selected, the objects are placed with extruder clearance areas exactly touching each other:

While this really might not present problems while actually printing, this prevents generating G-code, as PrusaSlicer produces an error message and disables G-code generation.

Selecting "Fast" geometry handling seems to be placing the same objects perfectly fine most of the time (although there is room for improvement of placement order, as described in #6474), but still not every single time:

Project file & How to reproduce

In PrusaSlicer, place multiple objects/instances on the bed. Select "Print Settings -> Output Options -> Sequential printing -> Complete individual objects"; right-click "Arrange" button and choose geometry handling "Balanced" or "Accurate"; left-click "Arrange" button. The objects are placed with extruder clearance areas exactly touching each other; PrusaSlicer produces following error: "Some objects are too close; your extruder will collide with them"; G-code generation is disabled.

Try the same several times with geometry handling "Fast". Most of the times the placement will be acceptable, but some of the times the same error will be produced.

An example of a project file: 003.zip

Checklist of files included above

• Project file
• Screenshot

Version of PrusaSlicer

2.6.1

Operating system

Ubuntu 23.04

Printer model

MK3S+ kit

[Jan-Soustruznik]

Hello, @staspika ,

Thank you for your report. We will try to fix in some next releases.

SPE-1909

Have a nice day