Eradicated admesh from TriangleMesh:

TriangleMesh newly only holds indexed_triangle_set and
TriangleMeshStats. TriangleMeshStats contains an excerpt of stl_stats.
TriangleMeshStats are updated when initializing with indexed_triangle_set.

Admesh triangle mesh fixing is newly only used when loading an STL.
AMF / 3MF / OBJ file formats are already indexed triangle sets, thus
they are no more converted to admesh stl_file format, nor fixed
through admesh repair machinery. When importing AMF / 3MF / OBJ files,
volume is calculated and if negative, all faces are flipped. Also
a bounding box and number of open edges is calculated.

Implemented its_number_of_patches(), its_num_open_edges()
Optimized its_split(), its_is_splittable() using a visitor pattern.

Reworked QHull integration into TriangleMesh:
    1) Face normals were not right.
    2) Indexed triangle set is newly emitted instead of duplicating
       vertices for each face.

Fixed cut_mesh(): Orient the triangulated faces correctly.

3 files changed, 1 insertions, 9 deletions

diff --git a/src/libslic3r/SLA/Hollowing.cpp b/src/libslic3r/SLA/Hollowing.cpp
index 55dae9430..9cac7f63b 100644
--- a/src/libslic3r/SLA/Hollowing.cpp
+++ b/src/libslic3r/SLA/Hollowing.cpp
@@ -286,8 +286,6 @@ void cut_drainholes(std::vector<ExPolygons> & obj_slices,
     
     if (mesh.empty()) return;
     
-    mesh.require_shared_vertices();
- 
     std::vector<ExPolygons> hole_slices = slice_mesh_ex(mesh.its, slicegrid, closing_radius, thr);
     
     if (obj_slices.size() != hole_slices.size())
@@ -316,7 +314,6 @@ void hollow_mesh(TriangleMesh &mesh, const Interior &interior, int flags)
         remove_inside_triangles(mesh, interior);
 
     mesh.merge(TriangleMesh{interior.mesh});
-    mesh.require_shared_vertices();
 }
 
 // Get the distance of p to the interior's zero iso_surface. Interior should
@@ -557,8 +554,7 @@ void remove_inside_triangles(TriangleMesh &mesh, const Interior &interior,
     new_faces = {};
 
     mesh = TriangleMesh{mesh.its};
-    mesh.repaired = true;
-    mesh.require_shared_vertices();
+    //FIXME do we want to repair the mesh? Are there duplicate vertices or flipped triangles?
 }
 
 }} // namespace Slic3r::sla
diff --git a/src/libslic3r/SLA/ReprojectPointsOnMesh.hpp b/src/libslic3r/SLA/ReprojectPointsOnMesh.hpp
index 20804193e..3ad7d62b1 100644
--- a/src/libslic3r/SLA/ReprojectPointsOnMesh.hpp
+++ b/src/libslic3r/SLA/ReprojectPointsOnMesh.hpp
@@ -33,7 +33,6 @@ inline void reproject_points_and_holes(ModelObject *object)
     if (!object || (!has_holes && !has_sppoints)) return;
 
     TriangleMesh rmsh = object->raw_mesh();
-    rmsh.require_shared_vertices();
     IndexedMesh emesh{rmsh};
 
     if (has_sppoints)
diff --git a/src/libslic3r/SLA/Rotfinder.cpp b/src/libslic3r/SLA/Rotfinder.cpp
index 5486741f2..196646dc9 100644
--- a/src/libslic3r/SLA/Rotfinder.cpp
+++ b/src/libslic3r/SLA/Rotfinder.cpp
@@ -205,7 +205,6 @@ inline bool is_on_floor(const SLAPrintObjectConfig &cfg)
 std::vector<XYRotation> get_chull_rotations(const TriangleMesh &mesh, size_t max_count)
 {
     TriangleMesh chull = mesh.convex_hull_3d();
-    chull.require_shared_vertices();
     double chull2d_area = chull.convex_hull().area();
     double area_threshold = chull2d_area / (scaled<double>(1e3) * scaled(1.));
 
@@ -299,7 +298,6 @@ struct RotfinderBoilerplate {
     static TriangleMesh get_mesh_to_rotate(const ModelObject &mo)
     {
         TriangleMesh mesh = mo.raw_mesh();
-        mesh.require_shared_vertices();
 
         ModelInstance *mi = mo.instances[0];
         auto rotation = Vec3d::Zero();
@@ -437,7 +435,6 @@ Vec2d find_min_z_height_rotation(const ModelObject &mo,
     RotfinderBoilerplate<1000> bp{mo, params};
 
     TriangleMesh chull = bp.mesh.convex_hull_3d();
-    chull.require_shared_vertices();
     auto inputs = reserve_vector<XYRotation>(chull.its.indices.size());
     auto rotcmp = [](const XYRotation &r1, const XYRotation &r2) {
         double xdiff = r1[X] - r2[X], ydiff = r1[Y] - r2[Y];