Neighboring objects generate overlapping rafts

[joris57]

Version

1.38.6

Operating system type + version

Windows 10

Behavior

As an example : load Gear_Bearing.stl and slice with raft -> a good raft is being generated.

Now right-click on the object and select 'Split', then slice again with raft.

The rafts now overlap badly and will print over each other, generating an uneven surface that represents a poor raft and risks to catch he nozzle.

[bubnikv]

This is a duplicate of #316
Supports are generated per object, and collisions of objects (and their supports) are not tested for by Slic3r.