Make plater work with new XS code

lib/Slic3r/GUI/Plater.pm

@@ -1271,9 +1271,8 @@ sub _trigger_model_object {
     	my $mesh = $model_object->mesh;
     	$mesh->repair;
         $self->convex_hull(Slic3r::Polygon->new(@{Math::ConvexHull::MonotoneChain::convex_hull($mesh->vertices)}));
-	    $self->facets(scalar @{$mesh->facets});
+	    $self->facets($mesh->facets_count);
 	    $self->vertices(scalar @{$mesh->vertices});
-	    
 	    $self->materials($model_object->materials_count);
 	}
 }

lib/Slic3r/GUI/PreviewCanvas.pm

@@ -49,13 +49,14 @@ sub new {
             color => COLORS->[ $color_idx % scalar(@{&COLORS}) ],
         };
         
+        my ($vertices, $facets) = ($mesh->vertices, $mesh->facets);
         {
-            my @verts = map @{ $mesh->vertices->[$_] }, map @$_, @{$mesh->facets};
+            my @verts = map @{ $vertices->[$_] }, map @$_, @$facets;
             $v->{verts} = OpenGL::Array->new_list(GL_FLOAT, @verts);
         }
         
         {
-            my @norms = map { @$_, @$_, @$_ } map normalize(triangle_normal(map $mesh->vertices->[$_], @$_)), @{$mesh->facets};
+            my @norms = map { @$_, @$_, @$_ } map normalize(triangle_normal(map $vertices->[$_], @$_)), @$facets;
             $v->{norms} = OpenGL::Array->new_list(GL_FLOAT, @norms);
         }
     }

xs/src/TriangleMesh.cpp

@@ -11,6 +11,12 @@
 
 namespace Slic3r {
 
+TriangleMesh::TriangleMesh()
+    : repaired(false)
+{
+    stl_initialize(&this->stl);
+}
+
 TriangleMesh::TriangleMesh(const TriangleMesh &other)
     : stl(other.stl), repaired(other.repaired)
 {
@@ -64,7 +70,6 @@ TriangleMesh::write_binary(char* output_file)
 
 void TriangleMesh::ReadFromPerl(SV* vertices, SV* facets)
 {
-    stl_initialize(&stl);
     stl.stats.type = inmemory;
     
     // count facets and allocate memory
@@ -559,7 +564,6 @@ TriangleMesh::split() const
         
         TriangleMesh* mesh = new TriangleMesh;
         meshes.push_back(mesh);
-        stl_initialize(&mesh->stl);
         mesh->stl.stats.type = inmemory;
         mesh->stl.stats.number_of_facets = facets.size();
         mesh->stl.stats.original_num_facets = mesh->stl.stats.number_of_facets;

xs/src/TriangleMesh.hpp

@@ -15,7 +15,7 @@ typedef std::vector<TriangleMesh*> TriangleMeshPtrs;
 class TriangleMesh
 {
     public:
-    TriangleMesh() : repaired(false) {};
+    TriangleMesh();
     TriangleMesh(const TriangleMesh &other);
     ~TriangleMesh();
     SV* to_SV();