Detection of curled edges to enhance slowdown for overhangs algorithm (#2056)

* Overhang perimeter handling

Updated code to handle overhang perimeters as an overhang and not as a bridge.

* Preparing to add curled extrusions identification

* Porting curling calculations from Prusa Slier 2.6.1

* Prototype 1 - slowdown extended to detect curled edges and further reduce speed

First prototype of the code submitted.

* Working prototype - 2

Code is now finally working - external perimeters are slowed down as needed when there is likelyhood of curling up.

ToDo:
1. Reslicing the model causes the algorithm not to run - need to find where this fails to trigger the call for this.
2. Slowdown of internal perimeters not working yet.

* Updated to use overhang wall speed instead of bridging speed for this algorithm

* Fixed bug in speed calculation and tweaked parameters for high speed printer

Fixed bug in speed calculation and tweaked parameters for high speed printer

* Attempting to fix "set started" not being set

* Parameter tweak after print tests

* Fixed estimation not running when model is re-sliced.

* Removing debug printf statements and fixed threading flag.

* Fixed threading

* Parameter tweaks following print tests

* Made this as an option in the GUI

* Reintroduced handling of bridges as per original design

* UI line toggling when option makes sense to be visible.

* Fixed bug in field visibility & made it default to off

* Code optimisation

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Co-authored-by: SoftFever <softfeverever@gmail.com>

src/libslic3r/PrintConfig.hpp

@@ -816,6 +816,7 @@ PRINT_CONFIG_CLASS_DEFINE(
     // Orca
     ((ConfigOptionBool,                 make_overhang_printable))
     ((ConfigOptionBool,                 extra_perimeters_on_overhangs))
+    ((ConfigOptionBool,                 slowdown_for_curled_perimeters))
 )
 
 PRINT_CONFIG_CLASS_DEFINE(