support blocker enforcer issue

[fbujold]

Version

2.3.0+64

Operating system type + version

windows 10

3D printer brand / version + firmware version (if known)

MK3S, MK2.5S

Behavior

I want to support holes on a vertical wall ONLY
I done not want to have the support all the way to the bed surface
tried painter blocker enforcer and combination of support always goes to platform.
Downloads.zip

Is this a new feature request?
Not a feature but a bug

Project File (.3MF) where problem occurs

Upload a PrusaSlicer Project File (.3MF) (Plater -> Export plate as 3MF for Slic3r PE 1.41.2 and older, File -> Save / Save Project for PrusaSlicer, Slic3r PE 1.42.0-alpha and newer)
Images (PNG, GIF, JPEG), PDFs or text files could be drag & dropped to the issue directly, while all other files need to be zipped first (.zip, .gz)

[bubnikv]

[bubnikv]

Testing snug supports

[bubnikv]

Fixed with af9c7c9

Implementing a new switch for the shape of support towers:
expanded to a grid (the old way) vs.
snug (like the upstream Slic3r, Cura or Ideamaker).

Snug supports suffered from the degeneracies when merging overhang islands
over a large number of layers when projecting the support towers down.
We borrowed the idea & a bit of code from Cura by simplifying the support
polygons by closing the concave cracks, see the smooth_outward() function
and the MutablePolygon class.