Reworked "only_retract_when_crossing_perimeters" feature, which

was terribly slow:
Introduced RetractWhenCrossingPerimeters.cpp,hpp
AABBTreeIndirect traverse template was extended to support early exit.

src/libslic3r/GCode.cpp

@@ -3090,7 +3090,7 @@ bool GCode::needs_retraction(const Polyline &travel, ExtrusionRole role)
         }
 
     if (m_config.only_retract_when_crossing_perimeters && m_layer != nullptr &&
-        m_config.fill_density.value > 0 && m_layer->any_internal_region_slice_contains(travel))
+        m_config.fill_density.value > 0 && m_retract_when_crossing_perimeters.travel_inside_internal_regions(*m_layer, travel))
         // Skip retraction if travel is contained in an internal slice *and*
         // internal infill is enabled (so that stringing is entirely not visible).
         //FIXME any_internal_region_slice_contains() is potentionally very slow, it shall test for the bounding boxes first.