1) Flipped the order of "discover_vertical_shells" and "process_external_surfaces",
now the external surfaces are expanded after "discover_vertical_shells"
aka "ensure vertical wall thickness" is solved.
2) Reworked LayerRegion::process_external_surfaces() to only expand into
"ensure vertical wall thickness" regions, also the expansion is done
in small steps to avoid overflowing into neighbor regions.
also:
Utility functions reserve_more(), reserve_power_of_2(), reserve_more_power_of_2()
Various SurfaceCollecion::filter_xxx() modified to accept an initializer list of surface types.
New bridges detector refactored to accept overhang boundaries.
BoundingBoxWrapper was moved from RetractCrossingPerimeters to AABBTreeIndirect.
into a graph with links to the layer above / below.
In addition:
Members of LayerRegion were made private, public interface const only.
this->m_xxx replaced with just m_xxx
SurfacesPtr was made a vector of const pointers.
Fix of "Bridging infill not connecting with infill set to 0%" #1301
Top, bottom and bridging areas are extended into infill as long
as the infill is not zero. If the infill is zero,
top, bottom and bridging areas wound not expand into these "void" areas.
With this commit, the top, bottom and bridging areas are allowed to expand
into the "void" areas as long as these "void" areas are supported below
with perimeters or some other non-empty infill, and slightly beyond
these supporting areas into the voids (currently hard coded to 1mm).
