From 8da54139c463a09ec899a9df6bccae16802dccdf Mon Sep 17 00:00:00 2001
From: bubnikv <bubnikv@gmail.com>
Date: Tue, 4 Jun 2019 22:06:42 +0200
Subject: [PATCH] WIP: Admesh - replacement of C memory allocation with std
 vectors

---
 CMakeLists.txt                               |   2 +-
 src/admesh/connect.cpp                       | 401 ++++++++-----------
 src/admesh/normals.cpp                       |  26 +-
 src/admesh/shared.cpp                        |  37 +-
 src/admesh/stl.h                             | 187 +++++----
 src/admesh/stl_io.cpp                        |  30 +-
 src/admesh/stlinit.cpp                       | 104 ++---
 src/admesh/util.cpp                          | 104 +++--
 src/libslic3r/Format/3mf.cpp                 |   2 +-
 src/libslic3r/Format/AMF.cpp                 |   2 +-
 src/libslic3r/Format/PRUS.cpp                |   6 +-
 src/libslic3r/Model.cpp                      |  18 +-
 src/libslic3r/SLA/SLASupportTreeIGL.cpp      |  17 +-
 src/libslic3r/SlicingAdaptive.cpp            |   4 +-
 src/libslic3r/TriangleMesh.cpp               |  83 ++--
 src/libslic3r/TriangleMesh.hpp               |   4 +-
 src/slic3r/GUI/Gizmos/GLGizmoSlaSupports.cpp |   8 +-
 17 files changed, 450 insertions(+), 585 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 719bdd04e..3d7157d5e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -60,7 +60,7 @@ if (MSVC)
     # /bigobj (Increase Number of Sections in .Obj file)
     # error C3859: virtual memory range for PCH exceeded; please recompile with a command line option of '-Zm90' or greater
     # Generate symbols at every build target, even for the release.
-    add_compile_options(-bigobj -Zm316 /Zi)
+    add_compile_options(-bigobj -Zm520 /Zi)
 endif ()
 
 # Display and check CMAKE_PREFIX_PATH
diff --git a/src/admesh/connect.cpp b/src/admesh/connect.cpp
index 3069251d3..b99f93f3d 100644
--- a/src/admesh/connect.cpp
+++ b/src/admesh/connect.cpp
@@ -97,18 +97,10 @@ void stl_check_facets_exact(stl_file *stl)
 	stl->stats.freed      = 0;
 	stl->stats.collisions = 0;
 	stl->M = (int)hash_size_from_nr_faces(stl->stats.number_of_facets);
-	for (uint32_t i = 0; i < stl->stats.number_of_facets; ++ i) {
-		// initialize neighbors list to -1 to mark unconnected edges
-		stl->neighbors_start[i].neighbor[0] = -1;
-		stl->neighbors_start[i].neighbor[1] = -1;
-		stl->neighbors_start[i].neighbor[2] = -1;
-	}
-	stl->heads = (stl_hash_edge**)calloc(stl->M, sizeof(*stl->heads));
-	if (stl->heads == NULL)
-		perror("stl_initialize_facet_check_exact");
-	stl->tail = (stl_hash_edge*)malloc(sizeof(stl_hash_edge));
-	if (stl->tail == NULL) 
-		perror("stl_initialize_facet_check_exact");
+	for (auto &neighbor : stl->neighbors_start)
+		neighbor.reset();
+	stl->heads.assign(stl->M, nullptr);
+	stl->tail = new stl_hash_edge;
 	stl->tail->next = stl->tail;
 	for (int i = 0; i < stl->M; ++ i)
 		stl->heads[i] = stl->tail;
@@ -180,7 +172,7 @@ static void insert_hash_edge(stl_file *stl, stl_hash_edge edge,
   stl_hash_edge *temp;
   if(link == stl->tail) {
     /* This list doesn't have any edges currently in it.  Add this one. */
-    new_edge = (stl_hash_edge*)malloc(sizeof(stl_hash_edge));
+    new_edge = new stl_hash_edge;
     if(new_edge == NULL) perror("insert_hash_edge");
     stl->stats.malloced++;
     *new_edge = edge;
@@ -192,7 +184,7 @@ static void insert_hash_edge(stl_file *stl, stl_hash_edge edge,
     match_neighbors(stl, &edge, link);
     /* Delete the matched edge from the list. */
     stl->heads[chain_number] = link->next;
-    free(link);
+    delete link;
     stl->stats.freed++;
     return;
   } else {
@@ -200,7 +192,7 @@ static void insert_hash_edge(stl_file *stl, stl_hash_edge edge,
     for(;;) {
       if(link->next == stl->tail) {
         /* This is the last item in the list. Insert a new edge. */
-        new_edge = (stl_hash_edge*)malloc(sizeof(stl_hash_edge));
+        new_edge = new stl_hash_edge;
         if(new_edge == NULL) perror("insert_hash_edge");
         stl->stats.malloced++;
         *new_edge = edge;
@@ -215,7 +207,7 @@ static void insert_hash_edge(stl_file *stl, stl_hash_edge edge,
         /* Delete the matched edge from the list. */
         temp = link->next;
         link->next = link->next->next;
-        free(temp);
+        delete temp;
         stl->stats.freed++;
         return;
       } else {
@@ -307,48 +299,38 @@ static void stl_free_edges(stl_file *stl)
     for (int i = 0; i < stl->M; i++) {
       for (stl_hash_edge *temp = stl->heads[i]; stl->heads[i] != stl->tail; temp = stl->heads[i]) {
         stl->heads[i] = stl->heads[i]->next;
-        free(temp);
+        delete temp;
         ++ stl->stats.freed;
       }
     }
   }
-  free(stl->heads);
-  stl->heads = nullptr;
-  free(stl->tail);
+  stl->heads.clear();
+  delete stl->tail;
   stl->tail = nullptr;
 }
 
 static void stl_initialize_facet_check_nearby(stl_file *stl)
 {
-  int i;
+	if (stl->error)
+		return;
 
-  if (stl->error) return;
+	stl->stats.malloced   = 0;
+	stl->stats.freed 	  = 0;
+	stl->stats.collisions = 0;
 
-  stl->stats.malloced = 0;
-  stl->stats.freed = 0;
-  stl->stats.collisions = 0;
+	/*  tolerance = STL_MAX(stl->stats.shortest_edge, tolerance);*/
+	/*  tolerance = STL_MAX((stl->stats.bounding_diameter / 500000.0), tolerance);*/
+	/*  tolerance *= 0.5;*/
+	stl->M = (int)hash_size_from_nr_faces(stl->stats.number_of_facets);
 
-  /*  tolerance = STL_MAX(stl->stats.shortest_edge, tolerance);*/
-  /*  tolerance = STL_MAX((stl->stats.bounding_diameter / 500000.0), tolerance);*/
-  /*  tolerance *= 0.5;*/
+	stl->heads.assign(stl->M, nullptr);
+	stl->tail = new stl_hash_edge;
+	stl->tail->next = stl->tail;
 
-  stl->M = (int)hash_size_from_nr_faces(stl->stats.number_of_facets);
-
-  stl->heads = (stl_hash_edge**)calloc(stl->M, sizeof(*stl->heads));
-  if(stl->heads == NULL) perror("stl_initialize_facet_check_nearby");
-
-  stl->tail = (stl_hash_edge*)malloc(sizeof(stl_hash_edge));
-  if(stl->tail == NULL) perror("stl_initialize_facet_check_nearby");
-
-  stl->tail->next = stl->tail;
-
-  for(i = 0; i < stl->M; i++) {
-    stl->heads[i] = stl->tail;
-  }
+	for (int i = 0; i < stl->M; ++ i)
+		stl->heads[i] = stl->tail;
 }
 
-
-
 static void
 stl_record_neighbors(stl_file *stl,
                      stl_hash_edge *edge_a, stl_hash_edge *edge_b) {
@@ -358,29 +340,19 @@ stl_record_neighbors(stl_file *stl,
   if (stl->error) return;
 
   /* Facet a's neighbor is facet b */
-  stl->neighbors_start[edge_a->facet_number].neighbor[edge_a->which_edge % 3] =
-    edge_b->facet_number;	/* sets the .neighbor part */
-
-  stl->neighbors_start[edge_a->facet_number].
-  which_vertex_not[edge_a->which_edge % 3] =
-    (edge_b->which_edge + 2) % 3; /* sets the .which_vertex_not part */
+  stl->neighbors_start[edge_a->facet_number].neighbor[edge_a->which_edge % 3] = edge_b->facet_number;	/* sets the .neighbor part */
+  stl->neighbors_start[edge_a->facet_number].which_vertex_not[edge_a->which_edge % 3] = (edge_b->which_edge + 2) % 3; /* sets the .which_vertex_not part */
 
   /* Facet b's neighbor is facet a */
-  stl->neighbors_start[edge_b->facet_number].neighbor[edge_b->which_edge % 3] =
-    edge_a->facet_number;	/* sets the .neighbor part */
-
-  stl->neighbors_start[edge_b->facet_number].
-  which_vertex_not[edge_b->which_edge % 3] =
-    (edge_a->which_edge + 2) % 3; /* sets the .which_vertex_not part */
+  stl->neighbors_start[edge_b->facet_number].neighbor[edge_b->which_edge % 3] = edge_a->facet_number;	/* sets the .neighbor part */
+  stl->neighbors_start[edge_b->facet_number].which_vertex_not[edge_b->which_edge % 3] = (edge_a->which_edge + 2) % 3; /* sets the .which_vertex_not part */
 
   if(   ((edge_a->which_edge < 3) && (edge_b->which_edge < 3))
         || ((edge_a->which_edge > 2) && (edge_b->which_edge > 2))) {
     /* these facets are oriented in opposite directions.  */
     /*  their normals are probably messed up. */
-    stl->neighbors_start[edge_a->facet_number].
-    which_vertex_not[edge_a->which_edge % 3] += 3;
-    stl->neighbors_start[edge_b->facet_number].
-    which_vertex_not[edge_b->which_edge % 3] += 3;
+    stl->neighbors_start[edge_a->facet_number].which_vertex_not[edge_a->which_edge % 3] += 3;
+    stl->neighbors_start[edge_b->facet_number].which_vertex_not[edge_b->which_edge % 3] += 3;
   }
 
 
@@ -561,8 +533,7 @@ stl_which_vertices_to_change(stl_file *stl, stl_hash_edge *edge_a,
     *facet1 = -1;
   } else {
     if(   (stl->neighbors_start[edge_a->facet_number].neighbor[v1a] == -1)
-          && (stl->neighbors_start[edge_a->facet_number].
-              neighbor[(v1a + 2) % 3] == -1)) {
+          && (stl->neighbors_start[edge_a->facet_number].neighbor[(v1a + 2) % 3] == -1)) {
       /* This vertex has no neighbors.  This is a good one to change */
       *facet1 = edge_a->facet_number;
       *vertex1 = v1a;
@@ -581,8 +552,7 @@ stl_which_vertices_to_change(stl_file *stl, stl_hash_edge *edge_a,
     *facet2 = -1;
   } else {
     if(   (stl->neighbors_start[edge_a->facet_number].neighbor[v2a] == -1)
-          && (stl->neighbors_start[edge_a->facet_number].
-              neighbor[(v2a + 2) % 3] == -1)) {
+          && (stl->neighbors_start[edge_a->facet_number].neighbor[(v2a + 2) % 3] == -1)) {
       /* This vertex has no neighbors.  This is a good one to change */
       *facet2 = edge_a->facet_number;
       *vertex2 = v2a;
@@ -595,140 +565,6 @@ stl_which_vertices_to_change(stl_file *stl, stl_hash_edge *edge_a,
   }
 }
 
-static void remove_facet(stl_file *stl, int facet_number)
-{
-	assert(! stl->error);
-	++ stl->stats.facets_removed;
-	/* Update list of connected edges */
-	stl_neighbors &neighbors = stl->neighbors_start[facet_number];
-	// Update statistics on unconnected triangle edges.
-	switch ((neighbors.neighbor[0] == -1) + (neighbors.neighbor[1] == -1) + (neighbors.neighbor[2] == -1)) {
-	case 0: // Facet has 3 neighbors
-		-- stl->stats.connected_facets_3_edge;
-		-- stl->stats.connected_facets_2_edge;
-		-- stl->stats.connected_facets_1_edge;
-		break;
-	case 1: // Facet has 2 neighbors
-		-- stl->stats.connected_facets_2_edge;
-		-- stl->stats.connected_facets_1_edge;
-		break;
-	case 2: // Facet has 1 neighbor
-		-- stl->stats.connected_facets_1_edge;
-	case 3: // Facet has 0 neighbors
-		break;
-	default:
-		assert(false);
-	}
-
-  	if (facet_number == -- stl->stats.number_of_facets)
-  		// Removing the last face is easy, just forget the last face.
-  		return;
-
-  	// Copy the face and neighborship from the last face to facet_number.
-  	stl->facet_start[facet_number] = stl->facet_start[stl->stats.number_of_facets];
-  	neighbors = stl->neighbors_start[stl->stats.number_of_facets];
-  	// Update neighborship of faces, which used to point to the last face, now moved to facet_number.
-  	for (int i = 0; i < 3; ++ i)
-    	if (neighbors.neighbor[i] != -1) {
-	    	int &other_face_idx = stl->neighbors_start[neighbors.neighbor[i]].neighbor[(neighbors.which_vertex_not[i] + 1) % 3];
-	  		if (other_face_idx != stl->stats.number_of_facets) {
-	    		printf("in remove_facet: neighbor = %d numfacets = %d this is wrong\n", other_face_idx, stl->stats.number_of_facets);
-	    		return;
-	  		}
-	  		other_face_idx = facet_number;
-  		}
-}
-
-static void remove_degenerate(stl_file *stl, int facet) 
-{
-	assert(! stl->error);
-
-	// Update statistics on face connectivity.
-	auto stl_update_connects_remove_1 = [stl](int facet_num) {
-		assert(! stl->error);
-		//FIXME when decreasing 3_edge, should I increase 2_edge etc?
-		switch ((stl->neighbors_start[facet_num].neighbor[0] == -1) + (stl->neighbors_start[facet_num].neighbor[1] == -1) + (stl->neighbors_start[facet_num].neighbor[2] == -1)) {
-		case 0: // Facet has 3 neighbors
-			-- stl->stats.connected_facets_3_edge; break;
-		case 1: // Facet has 2 neighbors
-			-- stl->stats.connected_facets_2_edge; break;
-		case 2: // Facet has 1 neighbor
-			-- stl->stats.connected_facets_1_edge; break;
-		case 3: // Facet has 0 neighbors
-			break;
-		default:
-			assert(false);
-	  	}
-	};
-
-	int edge_to_collapse = 0;
-   	if (stl->facet_start[facet].vertex[0] == stl->facet_start[facet].vertex[1]) {
-		if (stl->facet_start[facet].vertex[1] == stl->facet_start[facet].vertex[2]) {
-			// All 3 vertices are equal. Collapse the edge with no neighbor if it exists.
-			const int *nbr = stl->neighbors_start[facet].neighbor;
-			edge_to_collapse = (nbr[0] == -1) ? 0 : (nbr[1] == -1) ? 1 : 2;
-		} else {
-			edge_to_collapse = 0;
-		}
-  	} else if (stl->facet_start[facet].vertex[1] == stl->facet_start[facet].vertex[2]) {
-		edge_to_collapse = 1;
-  	} else if (stl->facet_start[facet].vertex[2] == stl->facet_start[facet].vertex[0]) {
-		edge_to_collapse = 2;
-  	} else {
-    	// No degenerate. Function shouldn't have been called.
-    	return;
-  	}
-
-	int edge[3] = { (edge_to_collapse + 1) % 3, (edge_to_collapse + 2) % 3, edge_to_collapse };
-	int neighbor[] = {
-		stl->neighbors_start[facet].neighbor[edge[0]],
-		stl->neighbors_start[facet].neighbor[edge[1]],
-		stl->neighbors_start[facet].neighbor[edge[2]]
-	};
-	int vnot[] = {
-		stl->neighbors_start[facet].which_vertex_not[edge[0]],
-		stl->neighbors_start[facet].which_vertex_not[edge[1]],
-		stl->neighbors_start[facet].which_vertex_not[edge[2]]
-	};
-	// Update statistics on edge connectivity.
-  	if (neighbor[0] == -1)
-    	stl_update_connects_remove_1(neighbor[1]);
-  	if (neighbor[1] == -1)
-    	stl_update_connects_remove_1(neighbor[0]);
-
-  	if (neighbor[0] >= 0) {
-		if (neighbor[1] >= 0) {
-			// Adjust the "flip" flag for the which_vertex_not values.
-			if (vnot[0] > 2) {
-				if (vnot[1] > 2) {
-					// The face to be removed has its normal flipped compared to the left & right neighbors, therefore after removing this face
-					// the two remaining neighbors will be oriented correctly.
-					vnot[0] -= 3;
-					vnot[1] -= 3;
-				} else
-					// One neighbor has its normal inverted compared to the face to be removed, the other is oriented equally.
-					// After removal, the two neighbors will have their normals flipped.
-					vnot[1] += 3;
-			} else if (vnot[1] > 2)
-				// One neighbor has its normal inverted compared to the face to be removed, the other is oriented equally.
-				// After removal, the two neighbors will have their normals flipped.
-				vnot[0] += 3;
-		}
-		stl->neighbors_start[neighbor[0]].neighbor[(vnot[0] + 1) % 3] = (neighbor[0] == neighbor[1]) ? -1 : neighbor[1];
-    	stl->neighbors_start[neighbor[0]].which_vertex_not[(vnot[0] + 1) % 3] = vnot[1];
-  	}
-  	if (neighbor[1] >= 0) {
-		stl->neighbors_start[neighbor[1]].neighbor[(vnot[1] + 1) % 3] = (neighbor[0] == neighbor[1]) ? -1 : neighbor[0];
-    	stl->neighbors_start[neighbor[1]].which_vertex_not[(vnot[1] + 1) % 3] = vnot[0];
-  	}
-	if (neighbor[2] >= 0) {
-		stl_update_connects_remove_1(neighbor[2]);
-		stl->neighbors_start[neighbor[2]].neighbor[(vnot[2] + 1) % 3] = -1;
-	}
-
-  	remove_facet(stl, facet);
-}
-
 void stl_remove_unconnected_facets(stl_file *stl)
 {
 	// A couple of things need to be done here.  One is to remove any completely unconnected facets (0 edges connected) since these are
@@ -737,12 +573,143 @@ void stl_remove_unconnected_facets(stl_file *stl)
 	if (stl->error)
 		return;
 
+	auto remove_facet = [stl](int facet_number)
+	{
+		++ stl->stats.facets_removed;
+		/* Update list of connected edges */
+		stl_neighbors &neighbors = stl->neighbors_start[facet_number];
+		// Update statistics on unconnected triangle edges.
+		switch ((neighbors.neighbor[0] == -1) + (neighbors.neighbor[1] == -1) + (neighbors.neighbor[2] == -1)) {
+		case 0: // Facet has 3 neighbors
+			-- stl->stats.connected_facets_3_edge;
+			-- stl->stats.connected_facets_2_edge;
+			-- stl->stats.connected_facets_1_edge;
+			break;
+		case 1: // Facet has 2 neighbors
+			-- stl->stats.connected_facets_2_edge;
+			-- stl->stats.connected_facets_1_edge;
+			break;
+		case 2: // Facet has 1 neighbor
+			-- stl->stats.connected_facets_1_edge;
+		case 3: // Facet has 0 neighbors
+			break;
+		default:
+			assert(false);
+		}
+
+	  	if (facet_number == -- stl->stats.number_of_facets)
+	  		// Removing the last face is easy, just forget the last face.
+	  		return;
+
+	  	// Copy the face and neighborship from the last face to facet_number.
+	  	stl->facet_start[facet_number] = stl->facet_start[stl->stats.number_of_facets];
+	  	neighbors = stl->neighbors_start[stl->stats.number_of_facets];
+	  	// Update neighborship of faces, which used to point to the last face, now moved to facet_number.
+	  	for (int i = 0; i < 3; ++ i)
+	    	if (neighbors.neighbor[i] != -1) {
+		    	int &other_face_idx = stl->neighbors_start[neighbors.neighbor[i]].neighbor[(neighbors.which_vertex_not[i] + 1) % 3];
+		  		if (other_face_idx != stl->stats.number_of_facets) {
+		    		printf("in remove_facet: neighbor = %d numfacets = %d this is wrong\n", other_face_idx, stl->stats.number_of_facets);
+		    		return;
+		  		}
+		  		other_face_idx = facet_number;
+	  		}
+	};
+
+	auto remove_degenerate = [stl, remove_facet](int facet)
+	{
+		// Update statistics on face connectivity.
+		auto stl_update_connects_remove_1 = [stl](int facet_num) {
+			assert(! stl->error);
+			//FIXME when decreasing 3_edge, should I increase 2_edge etc?
+			switch ((stl->neighbors_start[facet_num].neighbor[0] == -1) + (stl->neighbors_start[facet_num].neighbor[1] == -1) + (stl->neighbors_start[facet_num].neighbor[2] == -1)) {
+			case 0: // Facet has 3 neighbors
+				-- stl->stats.connected_facets_3_edge; break;
+			case 1: // Facet has 2 neighbors
+				-- stl->stats.connected_facets_2_edge; break;
+			case 2: // Facet has 1 neighbor
+				-- stl->stats.connected_facets_1_edge; break;
+			case 3: // Facet has 0 neighbors
+				break;
+			default:
+				assert(false);
+		  	}
+		};
+
+		int edge_to_collapse = 0;
+	   	if (stl->facet_start[facet].vertex[0] == stl->facet_start[facet].vertex[1]) {
+			if (stl->facet_start[facet].vertex[1] == stl->facet_start[facet].vertex[2]) {
+				// All 3 vertices are equal. Collapse the edge with no neighbor if it exists.
+				const int *nbr = stl->neighbors_start[facet].neighbor;
+				edge_to_collapse = (nbr[0] == -1) ? 0 : (nbr[1] == -1) ? 1 : 2;
+			} else {
+				edge_to_collapse = 0;
+			}
+	  	} else if (stl->facet_start[facet].vertex[1] == stl->facet_start[facet].vertex[2]) {
+			edge_to_collapse = 1;
+	  	} else if (stl->facet_start[facet].vertex[2] == stl->facet_start[facet].vertex[0]) {
+			edge_to_collapse = 2;
+	  	} else {
+	    	// No degenerate. Function shouldn't have been called.
+	    	return;
+	  	}
+
+		int edge[3] = { (edge_to_collapse + 1) % 3, (edge_to_collapse + 2) % 3, edge_to_collapse };
+		int neighbor[] = {
+			stl->neighbors_start[facet].neighbor[edge[0]],
+			stl->neighbors_start[facet].neighbor[edge[1]],
+			stl->neighbors_start[facet].neighbor[edge[2]]
+		};
+		int vnot[] = {
+			stl->neighbors_start[facet].which_vertex_not[edge[0]],
+			stl->neighbors_start[facet].which_vertex_not[edge[1]],
+			stl->neighbors_start[facet].which_vertex_not[edge[2]]
+		};
+		// Update statistics on edge connectivity.
+	  	if (neighbor[0] == -1)
+	    	stl_update_connects_remove_1(neighbor[1]);
+	  	if (neighbor[1] == -1)
+	    	stl_update_connects_remove_1(neighbor[0]);
+
+	  	if (neighbor[0] >= 0) {
+			if (neighbor[1] >= 0) {
+				// Adjust the "flip" flag for the which_vertex_not values.
+				if (vnot[0] > 2) {
+					if (vnot[1] > 2) {
+						// The face to be removed has its normal flipped compared to the left & right neighbors, therefore after removing this face
+						// the two remaining neighbors will be oriented correctly.
+						vnot[0] -= 3;
+						vnot[1] -= 3;
+					} else
+						// One neighbor has its normal inverted compared to the face to be removed, the other is oriented equally.
+						// After removal, the two neighbors will have their normals flipped.
+						vnot[1] += 3;
+				} else if (vnot[1] > 2)
+					// One neighbor has its normal inverted compared to the face to be removed, the other is oriented equally.
+					// After removal, the two neighbors will have their normals flipped.
+					vnot[0] += 3;
+			}
+			stl->neighbors_start[neighbor[0]].neighbor[(vnot[0] + 1) % 3] = (neighbor[0] == neighbor[1]) ? -1 : neighbor[1];
+	    	stl->neighbors_start[neighbor[0]].which_vertex_not[(vnot[0] + 1) % 3] = vnot[1];
+	  	}
+	  	if (neighbor[1] >= 0) {
+			stl->neighbors_start[neighbor[1]].neighbor[(vnot[1] + 1) % 3] = (neighbor[0] == neighbor[1]) ? -1 : neighbor[0];
+	    	stl->neighbors_start[neighbor[1]].which_vertex_not[(vnot[1] + 1) % 3] = vnot[0];
+	  	}
+		if (neighbor[2] >= 0) {
+			stl_update_connects_remove_1(neighbor[2]);
+			stl->neighbors_start[neighbor[2]].neighbor[(vnot[2] + 1) % 3] = -1;
+		}
+
+	  	remove_facet(facet);
+	};
+
 	// remove degenerate facets
 	for (uint32_t i = 0; i < stl->stats.number_of_facets;)
 		if (stl->facet_start[i].vertex[0] == stl->facet_start[i].vertex[1] ||
 			stl->facet_start[i].vertex[0] == stl->facet_start[i].vertex[2] ||
 			stl->facet_start[i].vertex[1] == stl->facet_start[i].vertex[2]) {
-			remove_degenerate(stl, i);
+			remove_degenerate(i);
 //			assert(stl_validate(stl));
 		} else
 			++ i;
@@ -754,7 +721,7 @@ void stl_remove_unconnected_facets(stl_file *stl)
 				stl->neighbors_start[i].neighbor[1] == -1 &&
 				stl->neighbors_start[i].neighbor[2] == -1) {
 				// This facet is completely unconnected.  Remove it.
-				remove_facet(stl, i);
+				remove_facet(i);
 				assert(stl_validate(stl));
 			} else
 				++ i;
@@ -850,8 +817,7 @@ stl_fill_holes(stl_file *stl) {
           }
           break;
         } else {
-          vnot = stl->neighbors_start[facet_num].
-                 which_vertex_not[next_edge];
+          vnot = stl->neighbors_start[facet_num].which_vertex_not[next_edge];
           facet_num = next_facet;
         }
 
@@ -867,27 +833,14 @@ Try using a smaller tolerance or don't do a nearby check\n");
   }
 }
 
-void
-stl_add_facet(stl_file *stl, stl_facet *new_facet) {
-  if (stl->error) return;
-
-  stl->stats.facets_added += 1;
-  if(stl->stats.facets_malloced < (int)stl->stats.number_of_facets + 1) {
-    stl->facet_start = (stl_facet*)realloc(stl->facet_start,
-                                           (sizeof(stl_facet) * (stl->stats.facets_malloced + 256)));
-    if(stl->facet_start == NULL) perror("stl_add_facet");
-    stl->neighbors_start = (stl_neighbors*)realloc(stl->neighbors_start,
-                           (sizeof(stl_neighbors) * (stl->stats.facets_malloced + 256)));
-    if(stl->neighbors_start == NULL) perror("stl_add_facet");
-    stl->stats.facets_malloced += 256;
-  }
-  stl->facet_start[stl->stats.number_of_facets] = *new_facet;
-
-  /* note that the normal vector is not set here, just initialized to 0 */
-  stl->facet_start[stl->stats.number_of_facets].normal = stl_normal::Zero();
-
-  stl->neighbors_start[stl->stats.number_of_facets].neighbor[0] = -1;
-  stl->neighbors_start[stl->stats.number_of_facets].neighbor[1] = -1;
-  stl->neighbors_start[stl->stats.number_of_facets].neighbor[2] = -1;
-  stl->stats.number_of_facets += 1;
+void stl_add_facet(stl_file *stl, const stl_facet *new_facet)
+{
+	if (stl->error)
+		return;
+  	++ stl->stats.facets_added;
+  	++ stl->stats.number_of_facets;
+  	stl->facet_start.emplace_back(*new_facet);
+  	// note that the normal vector is not set here, just initialized to 0.
+  	stl->facet_start[stl->stats.number_of_facets].normal = stl_normal::Zero();
+  	stl->neighbors_start.emplace_back();
 }
diff --git a/src/admesh/normals.cpp b/src/admesh/normals.cpp
index ecf08b59c..e11f1a3c1 100644
--- a/src/admesh/normals.cpp
+++ b/src/admesh/normals.cpp
@@ -84,7 +84,6 @@ stl_reverse_facet(stl_file *stl, int facet_num) {
 
 void
 stl_fix_normal_directions(stl_file *stl) {
-  char *norm_sw;
   /*  int edge_num;*/
   /*  int vnot;*/
   int checked = 0;
@@ -101,7 +100,6 @@ stl_fix_normal_directions(stl_file *stl) {
   struct stl_normal *newn;
   struct stl_normal *temp;
 
-  int* reversed_ids;
   int reversed_count = 0;
   int id;
   int force_exit = 0;
@@ -112,20 +110,15 @@ stl_fix_normal_directions(stl_file *stl) {
   if (stl->stats.number_of_facets == 0) return;
 
   /* Initialize linked list. */
-  head = (struct stl_normal*)malloc(sizeof(struct stl_normal));
-  if(head == NULL) perror("stl_fix_normal_directions");
-  tail = (struct stl_normal*)malloc(sizeof(struct stl_normal));
-  if(tail == NULL) perror("stl_fix_normal_directions");
+  head = new stl_normal;
+  tail = new stl_normal;
   head->next = tail;
   tail->next = tail;
 
   /* Initialize list that keeps track of already fixed facets. */
-  norm_sw = (char*)calloc(stl->stats.number_of_facets, sizeof(char));
-  if(norm_sw == NULL) perror("stl_fix_normal_directions");
-
+  std::vector<char> norm_sw(stl->stats.number_of_facets, 0);
   /* Initialize list that keeps track of reversed facets. */
-  reversed_ids = (int*)calloc(stl->stats.number_of_facets, sizeof(int));
-  if (reversed_ids == NULL) perror("stl_fix_normal_directions reversed_ids");
+  std::vector<int> reversed_ids(stl->stats.number_of_facets, 0);
 
   facet_num = 0;
   /* If normal vector is not within tolerance and backwards:
@@ -166,8 +159,7 @@ stl_fix_normal_directions(stl_file *stl) {
         /* If we haven't fixed this facet yet, add it to the list: */
         if(norm_sw[stl->neighbors_start[facet_num].neighbor[j]] != 1) {
           /* Add node to beginning of list. */
-          newn = (struct stl_normal*)malloc(sizeof(struct stl_normal));
-          if(newn == NULL) perror("stl_fix_normal_directions");
+          newn = new stl_normal;
           newn->facet_num = stl->neighbors_start[facet_num].neighbor[j];
           newn->next = head->next;
           head->next = newn;
@@ -187,7 +179,7 @@ stl_fix_normal_directions(stl_file *stl) {
       }
       temp = head->next;	/* Delete this facet from the list. */
       head->next = head->next->next;
-      free(temp);
+      delete temp;
     } else { /* if we ran out of facets to fix: */
       /* All of the facets in this part have been fixed. */
       stl->stats.number_of_parts += 1;
@@ -213,10 +205,8 @@ stl_fix_normal_directions(stl_file *stl) {
       }
     }
   }
-  free(head);
-  free(tail);
-  free(reversed_ids);
-  free(norm_sw);
+  delete head;
+  delete tail;
 }
 
 static int stl_check_normal_vector(stl_file *stl, int facet_num, int normal_fix_flag) {
diff --git a/src/admesh/shared.cpp b/src/admesh/shared.cpp
index 2ad270903..8162c6a8d 100644
--- a/src/admesh/shared.cpp
+++ b/src/admesh/shared.cpp
@@ -31,17 +31,8 @@
 
 void stl_invalidate_shared_vertices(stl_file *stl)
 {
- 	if (stl->error) 
-    	return;
-
-  	if (stl->v_indices != nullptr) {
-    	free(stl->v_indices);
-    	stl->v_indices = nullptr;
-  	}
-  	if (stl->v_shared != nullptr) {
-    	free(stl->v_shared);
-    	stl->v_shared = nullptr;
-	}
+  	stl->v_indices.clear();
+  	stl->v_shared.clear();
 }
 
 void stl_generate_shared_vertices(stl_file *stl)
@@ -53,23 +44,11 @@ void stl_generate_shared_vertices(stl_file *stl)
 	stl_invalidate_shared_vertices(stl);
 
 	// 3 indices to vertex per face
-	stl->v_indices = (v_indices_struct*)calloc(stl->stats.number_of_facets, sizeof(v_indices_struct));
-	if (stl->v_indices == nullptr) 
-		perror("stl_generate_shared_vertices");
+	stl->v_indices.assign(stl->stats.number_of_facets, v_indices_struct());
 	// Shared vertices (3D coordinates)
-	stl->v_shared = (stl_vertex*)calloc((stl->stats.number_of_facets / 2), sizeof(stl_vertex));
-	if (stl->v_shared == nullptr) 
-		perror("stl_generate_shared_vertices");
-	stl->stats.shared_malloced = stl->stats.number_of_facets / 2;
+	stl->v_shared.assign(stl->stats.number_of_facets / 2, stl_vertex());
 	stl->stats.shared_vertices = 0;
 
-	for (uint32_t i = 0; i < stl->stats.number_of_facets; ++ i) {
-		// vertex index -1 means no shared vertex was assigned yet.
-		stl->v_indices[i].vertex[0] = -1;
-		stl->v_indices[i].vertex[1] = -1;
-		stl->v_indices[i].vertex[2] = -1;
-	}
-
 	// A degenerate mesh may contain loops: Traversing a fan will end up in an endless loop
 	// while never reaching the starting face. To avoid these endless loops, traversed faces at each fan traversal
 	// are marked with a unique fan_traversal_stamp.
@@ -82,13 +61,7 @@ void stl_generate_shared_vertices(stl_file *stl)
 				// Shared vertex was already assigned.
 				continue;
 			// Create a new shared vertex.
-			if (stl->stats.shared_vertices == stl->stats.shared_malloced) {
-				stl->stats.shared_malloced += 1024;
-				stl->v_shared = (stl_vertex*)realloc(stl->v_shared, stl->stats.shared_malloced * sizeof(stl_vertex));
-				if(stl->v_shared == nullptr) 
-					perror("stl_generate_shared_vertices");
-			}
-			stl->v_shared[stl->stats.shared_vertices] = stl->facet_start[facet_idx].vertex[j];
+			stl->v_shared.emplace_back(stl->facet_start[facet_idx].vertex[j]);
 			// Traverse the fan around the j-th vertex of the i-th face, assign the newly created shared vertex index to all the neighboring triangles in the triangle fan.
 			int  facet_in_fan_idx 	= facet_idx;
 			bool edge_direction 	= false;
diff --git a/src/admesh/stl.h b/src/admesh/stl.h
index 5ecd94bd1..345951121 100644
--- a/src/admesh/stl.h
+++ b/src/admesh/stl.h
@@ -27,6 +27,7 @@
 #include <stdint.h>
 #include <stddef.h>
 
+#include <vector>
 #include <Eigen/Geometry> 
 
 // Size of the binary STL header, free form.
@@ -44,18 +45,18 @@ static_assert(sizeof(stl_vertex) == 12, "size of stl_vertex incorrect");
 static_assert(sizeof(stl_normal) == 12, "size of stl_normal incorrect");
 
 struct stl_facet {
-  stl_normal normal;
-  stl_vertex vertex[3];
-  char       extra[2];
+	stl_normal normal;
+	stl_vertex vertex[3];
+	char       extra[2];
 
-  stl_facet  rotated(const Eigen::Quaternion<float, Eigen::DontAlign> &rot) {
-    stl_facet out;
-    out.normal    = rot * this->normal;
-    out.vertex[0] = rot * this->vertex[0];
-    out.vertex[1] = rot * this->vertex[1];
-    out.vertex[2] = rot * this->vertex[2];
-    return out;
-  }
+	stl_facet  rotated(const Eigen::Quaternion<float, Eigen::DontAlign> &rot) const {
+		stl_facet out;
+		out.normal    = rot * this->normal;
+		out.vertex[0] = rot * this->vertex[0];
+		out.vertex[1] = rot * this->vertex[1];
+		out.vertex[2] = rot * this->vertex[2];
+		return out;
+	}
 };
 
 #define SIZEOF_STL_FACET       50
@@ -67,86 +68,100 @@ static_assert(sizeof(stl_facet) >= SIZEOF_STL_FACET, "size of stl_facet incorrec
 
 typedef enum {binary, ascii, inmemory} stl_type;
 
-typedef struct {
-  stl_vertex p1;
-  stl_vertex p2;
-  int        facet_number;
-} stl_edge;
+struct stl_edge {
+	stl_vertex p1;
+	stl_vertex p2;
+	int        facet_number;
+};
 
-typedef struct stl_hash_edge {
-  // Key of a hash edge: sorted vertices of the edge.
-  uint32_t       key[6];
-  // Compare two keys.
-  bool operator==(const stl_hash_edge &rhs) { return memcmp(key, rhs.key, sizeof(key)) == 0; }
-  bool operator!=(const stl_hash_edge &rhs) { return ! (*this == rhs); }
-  int  hash(int M) const { return ((key[0] / 11 + key[1] / 7 + key[2] / 3) ^ (key[3] / 11  + key[4] / 7 + key[5] / 3)) % M; }
-  // Index of a facet owning this edge.
-  int            facet_number;
-  // Index of this edge inside the facet with an index of facet_number.
-  // If this edge is stored backwards, which_edge is increased by 3.
-  int            which_edge;
-  struct stl_hash_edge  *next;
-} stl_hash_edge;
+struct stl_hash_edge {
+	// Key of a hash edge: sorted vertices of the edge.
+	uint32_t       key[6];
+	// Compare two keys.
+	bool operator==(const stl_hash_edge &rhs) { return memcmp(key, rhs.key, sizeof(key)) == 0; }
+	bool operator!=(const stl_hash_edge &rhs) { return ! (*this == rhs); }
+	int  hash(int M) const { return ((key[0] / 11 + key[1] / 7 + key[2] / 3) ^ (key[3] / 11  + key[4] / 7 + key[5] / 3)) % M; }
+	// Index of a facet owning this edge.
+	int            facet_number;
+	// Index of this edge inside the facet with an index of facet_number.
+	// If this edge is stored backwards, which_edge is increased by 3.
+	int            which_edge;
+	struct stl_hash_edge  *next;
+};
 
-typedef struct {
-  // Index of a neighbor facet.
-  int   neighbor[3];
-  // Index of an opposite vertex at the neighbor face.
-  char  which_vertex_not[3];
-} stl_neighbors;
+struct stl_neighbors {
+  	stl_neighbors() { reset(); }
+  	void reset() {
+  		neighbor[0] = -1;
+  		neighbor[1] = -1;
+  		neighbor[2] = -1;
+  		which_vertex_not[0] = -1;
+  		which_vertex_not[1] = -1;
+  		which_vertex_not[2] = -1;
+  	}
 
-typedef struct {
-  int   vertex[3];
-} v_indices_struct;
+	// Index of a neighbor facet.
+  	int   neighbor[3];
+  	// Index of an opposite vertex at the neighbor face.
+  	char  which_vertex_not[3];
+};
 
-typedef struct {
-  char          header[81];
-  stl_type      type;
-  uint32_t      number_of_facets;
-  stl_vertex    max;
-  stl_vertex    min;
-  stl_vertex    size;
-  float         bounding_diameter;
-  float         shortest_edge;
-  float         volume;
-  unsigned      number_of_blocks;
-  int           connected_edges;
-  int           connected_facets_1_edge;
-  int           connected_facets_2_edge;
-  int           connected_facets_3_edge;
-  int           facets_w_1_bad_edge;
-  int           facets_w_2_bad_edge;
-  int           facets_w_3_bad_edge;
-  int           original_num_facets;
-  int           edges_fixed;
-  int           degenerate_facets;
-  int           facets_removed;
-  int           facets_added;
-  int           facets_reversed;
-  int           backwards_edges;
-  int           normals_fixed;
-  int           number_of_parts;
-  int           malloced;
-  int           freed;
-  int           facets_malloced;
-  int           collisions;
-  int           shared_vertices;
-  int           shared_malloced;
-} stl_stats;
+struct v_indices_struct {
+	// -1 means no vertex index has been assigned yet
+	v_indices_struct() { vertex[0] = -1; vertex[1] = -1; vertex[2] = -1; }
+  	int   vertex[3];
+};
 
-typedef struct {
-  FILE          *fp;
-  stl_facet     *facet_start;
-  stl_hash_edge **heads;
-  stl_hash_edge *tail;
-  int           M;
-  stl_neighbors *neighbors_start;
-  v_indices_struct *v_indices;
-  stl_vertex    *v_shared;
-  stl_stats     stats;
-  char          error;
-} stl_file;
+struct stl_stats {
+	char          header[81];
+	stl_type      type;
+	uint32_t      number_of_facets;
+	stl_vertex    max;
+	stl_vertex    min;
+	stl_vertex    size;
+	float         bounding_diameter;
+	float         shortest_edge;
+	float         volume;
+	unsigned      number_of_blocks;
+	int           connected_edges;
+	int           connected_facets_1_edge;
+	int           connected_facets_2_edge;
+	int           connected_facets_3_edge;
+	int           facets_w_1_bad_edge;
+	int           facets_w_2_bad_edge;
+	int           facets_w_3_bad_edge;
+	int           original_num_facets;
+	int           edges_fixed;
+	int           degenerate_facets;
+	int           facets_removed;
+	int           facets_added;
+	int           facets_reversed;
+	int           backwards_edges;
+	int           normals_fixed;
+	int           number_of_parts;
+	int           shared_vertices;
 
+	// hash table statistics
+	int           malloced;
+	int           freed;
+	int           collisions;
+};
+
+struct stl_file {
+	FILE          			   	   *fp;
+	std::vector<stl_facet>     		facet_start;
+	std::vector<stl_neighbors> 		neighbors_start;
+	// Hash table on edges
+	std::vector<stl_hash_edge*> 	heads;
+	stl_hash_edge* 					tail;
+	int           					M;
+	// Indexed face set
+	std::vector<v_indices_struct> 	v_indices;
+	std::vector<stl_vertex>       	v_shared;
+	// Statistics
+	stl_stats     					stats;
+	char          					error;
+};
 
 extern void stl_open(stl_file *stl, const char *file);
 extern void stl_close(stl_file *stl);
@@ -272,7 +287,7 @@ extern void stl_allocate(stl_file *stl);
 extern void stl_read(stl_file *stl, int first_facet, bool first);
 extern void stl_facet_stats(stl_file *stl, stl_facet facet, bool &first);
 extern void stl_reallocate(stl_file *stl);
-extern void stl_add_facet(stl_file *stl, stl_facet *new_facet);
+extern void stl_add_facet(stl_file *stl, const stl_facet *new_facet);
 
 extern void stl_clear_error(stl_file *stl);
 extern int stl_get_error(stl_file *stl);
diff --git a/src/admesh/stl_io.cpp b/src/admesh/stl_io.cpp
index 85f66785b..81060c0a3 100644
--- a/src/admesh/stl_io.cpp
+++ b/src/admesh/stl_io.cpp
@@ -109,7 +109,6 @@ Normals fixed         : %5d\n", stl->stats.normals_fixed);
 
 void
 stl_write_ascii(stl_file *stl, const char *file, const char *label) {
-  int       i;
   char      *error_msg;
 
   if (stl->error) return;
@@ -129,7 +128,7 @@ stl_write_ascii(stl_file *stl, const char *file, const char *label) {
 
   fprintf(fp, "solid  %s\n", label);
 
-  for(i = 0; i < stl->stats.number_of_facets; i++) {
+  for (uint32_t i = 0; i < stl->stats.number_of_facets; ++ i) {
     fprintf(fp, "  facet normal % .8E % .8E % .8E\n",
             stl->facet_start[i].normal(0), stl->facet_start[i].normal(1),
             stl->facet_start[i].normal(2));
@@ -154,7 +153,6 @@ stl_write_ascii(stl_file *stl, const char *file, const char *label) {
 
 void
 stl_print_neighbors(stl_file *stl, char *file) {
-  int i;
   FILE *fp;
   char *error_msg;
 
@@ -173,7 +171,7 @@ stl_print_neighbors(stl_file *stl, char *file) {
     return;
   }
 
-  for(i = 0; i < stl->stats.number_of_facets; i++) {
+  for (uint32_t i = 0; i < stl->stats.number_of_facets; i++) {
     fprintf(fp, "%d, %d,%d, %d,%d, %d,%d\n",
             i,
             stl->neighbors_start[i].neighbor[0],
@@ -200,7 +198,6 @@ void stl_internal_reverse_quads(char *buf, size_t cnt)
 void
 stl_write_binary(stl_file *stl, const char *file, const char *label) {
   FILE      *fp;
-  int       i;
   char      *error_msg;
 
   if (stl->error) return;
@@ -219,13 +216,13 @@ stl_write_binary(stl_file *stl, const char *file, const char *label) {
   }
 
   fprintf(fp, "%s", label);
-  for(i = strlen(label); i < LABEL_SIZE; i++) putc(0, fp);
+  for(size_t i = strlen(label); i < LABEL_SIZE; i++) putc(0, fp);
 
   fseek(fp, LABEL_SIZE, SEEK_SET);
 #ifdef BOOST_LITTLE_ENDIAN
   fwrite(&stl->stats.number_of_facets, 4, 1, fp);
-  for (i = 0; i < stl->stats.number_of_facets; ++ i)
-    fwrite(stl->facet_start + i, SIZEOF_STL_FACET, 1, fp);
+  for (const stl_facet &facet : stl->facet_start)
+	  fwrite(&facet, SIZEOF_STL_FACET, 1, fp);
 #else /* BOOST_LITTLE_ENDIAN */
   char buffer[50];
   // Convert the number of facets to little endian.
@@ -288,8 +285,6 @@ stl_write_neighbor(stl_file *stl, int facet) {
 void
 stl_write_quad_object(stl_file *stl, char *file) {
   FILE      *fp;
-  int       i;
-  int       j;
   char      *error_msg;
   stl_vertex connect_color = stl_vertex::Zero();
   stl_vertex uncon_1_color = stl_vertex::Zero();
@@ -313,10 +308,10 @@ stl_write_quad_object(stl_file *stl, char *file) {
   }
 
   fprintf(fp, "CQUAD\n");
-  for(i = 0; i < stl->stats.number_of_facets; i++) {
-    j = ((stl->neighbors_start[i].neighbor[0] == -1) +
-         (stl->neighbors_start[i].neighbor[1] == -1) +
-         (stl->neighbors_start[i].neighbor[2] == -1));
+  for (uint32_t i = 0; i < stl->stats.number_of_facets; i++) {
+    int j = ((stl->neighbors_start[i].neighbor[0] == -1) +
+             (stl->neighbors_start[i].neighbor[1] == -1) +
+             (stl->neighbors_start[i].neighbor[2] == -1));
     if(j == 0) {
       color = connect_color;
     } else if(j == 1) {
@@ -346,9 +341,8 @@ stl_write_quad_object(stl_file *stl, char *file) {
   fclose(fp);
 }
 
-void
-stl_write_dxf(stl_file *stl, const char *file, char *label) {
-  int       i;
+void stl_write_dxf(stl_file *stl, const char *file, char *label) 
+{
   FILE      *fp;
   char      *error_msg;
 
@@ -375,7 +369,7 @@ stl_write_dxf(stl_file *stl, const char *file, char *label) {
 
   fprintf(fp, "0\nSECTION\n2\nENTITIES\n");
 
-  for(i = 0; i < stl->stats.number_of_facets; i++) {
+  for (uint32_t i = 0; i < stl->stats.number_of_facets; i++) {
     fprintf(fp, "0\n3DFACE\n8\n0\n");
     fprintf(fp, "10\n%f\n20\n%f\n30\n%f\n",
             stl->facet_start[i].vertex[0](0), stl->facet_start[i].vertex[0](1),
diff --git a/src/admesh/stlinit.cpp b/src/admesh/stlinit.cpp
index 911f4f5e8..81b7914c3 100644
--- a/src/admesh/stlinit.cpp
+++ b/src/admesh/stlinit.cpp
@@ -35,22 +35,38 @@
 #error "SEEK_SET not defined"
 #endif
 
-void
-stl_open(stl_file *stl, const char *file) {
-  stl_initialize(stl);
-  stl_count_facets(stl, file);
-  stl_allocate(stl);
-  stl_read(stl, 0, true);
-  if (stl->fp != nullptr) {
-	  fclose(stl->fp);
-	  stl->fp = nullptr;
-  }
+void stl_open(stl_file *stl, const char *file)
+{
+	stl_initialize(stl);
+	stl_count_facets(stl, file);
+	stl_allocate(stl);
+	stl_read(stl, 0, true);
+	if (stl->fp != nullptr) {
+	  	fclose(stl->fp);
+	  	stl->fp = nullptr;
+	}
 }
 
-void
-stl_initialize(stl_file *stl) {
-  memset(stl, 0, sizeof(stl_file));
-  stl->stats.volume = -1.0;
+void stl_initialize(stl_file *stl)
+{
+	stl->fp = nullptr;
+	stl->tail = nullptr;
+	stl->M = 0;
+	stl->error = 0;
+	stl->facet_start.clear();
+	stl->neighbors_start.clear();
+	stl->v_indices.clear();
+	stl->v_shared.clear();
+  	memset(&stl->stats, 0, sizeof(stl_stats));
+  	stl->stats.volume = -1.0;
+}
+
+void stl_close(stl_file *stl)
+{
+	assert(stl->fp == nullptr);
+	assert(stl->heads.empty());
+	assert(stl->tail == nullptr);
+	stl_initialize(stl);
 }
 
 #ifndef BOOST_LITTLE_ENDIAN
@@ -175,20 +191,14 @@ stl_count_facets(stl_file *stl, const char *file) {
   stl->stats.original_num_facets = stl->stats.number_of_facets;
 }
 
-void
-stl_allocate(stl_file *stl) {
-  if (stl->error) return;
-
-  /*  Allocate memory for the entire .STL file */
-  stl->facet_start = (stl_facet*)calloc(stl->stats.number_of_facets,
-                                        sizeof(stl_facet));
-  if(stl->facet_start == NULL) perror("stl_initialize");
-  stl->stats.facets_malloced = stl->stats.number_of_facets;
-
-  /* Allocate memory for the neighbors list */
-  stl->neighbors_start = (stl_neighbors*)
-                         calloc(stl->stats.number_of_facets, sizeof(stl_neighbors));
-  if(stl->facet_start == NULL) perror("stl_initialize");
+void stl_allocate(stl_file *stl) 
+{
+	if (stl->error) 
+		return;
+  	//  Allocate memory for the entire .STL file.
+  	stl->facet_start.assign(stl->stats.number_of_facets, stl_facet());
+  	// Allocate memory for the neighbors list.
+  	stl->neighbors_start.assign(stl->stats.number_of_facets, stl_neighbors());
 }
 
 void
@@ -237,23 +247,14 @@ stl_open_merge(stl_file *stl, char *file_to_merge) {
   stl->fp=origFp;
 }
 
-extern void
-stl_reallocate(stl_file *stl) {
-  if (stl->error) return;
-  /*  Reallocate more memory for the .STL file(s) */
-  stl->facet_start = (stl_facet*)realloc(stl->facet_start, stl->stats.number_of_facets *
-                                         sizeof(stl_facet));
-  if(stl->facet_start == NULL) perror("stl_initialize");
-  stl->stats.facets_malloced = stl->stats.number_of_facets;
-
-  /* Reallocate more memory for the neighbors list */
-  stl->neighbors_start = (stl_neighbors*)
-                         realloc(stl->neighbors_start, stl->stats.number_of_facets *
-                                 sizeof(stl_neighbors));
-  if(stl->facet_start == NULL) perror("stl_initialize");
+void stl_reallocate(stl_file *stl) 
+{
+  	if (stl->error) 
+  		return;
+	stl->facet_start.resize(stl->stats.number_of_facets);
+	stl->neighbors_start.resize(stl->stats.number_of_facets);
 }
 
-
 /* Reads the contents of the file pointed to by stl->fp into the stl structure,
    starting at facet first_facet.  The second argument says if it's our first
    time running this for the stl and therefore we should reset our max and min stats. */
@@ -366,20 +367,3 @@ void stl_facet_stats(stl_file *stl, stl_facet facet, bool &first)
   	stl->stats.max = stl->stats.max.cwiseMax(facet.vertex[i]);
   }
 }
-
-void stl_close(stl_file *stl)
-{
-	assert(stl->fp == nullptr);
-	assert(stl->heads == nullptr);
-	assert(stl->tail == nullptr);
-
-	if (stl->facet_start != NULL)
-		free(stl->facet_start);
-	if (stl->neighbors_start != NULL)
-		free(stl->neighbors_start);
-	if (stl->v_indices != NULL)
-		free(stl->v_indices);
-	if (stl->v_shared != NULL)
-		free(stl->v_shared);
-	memset(stl, 0, sizeof(stl_file));
-}
diff --git a/src/admesh/util.cpp b/src/admesh/util.cpp
index c2d2c2726..61e0d11e7 100644
--- a/src/admesh/util.cpp
+++ b/src/admesh/util.cpp
@@ -32,45 +32,39 @@ static float get_area(stl_facet *facet);
 static float get_volume(stl_file *stl);
 
 
-void
-stl_verify_neighbors(stl_file *stl) {
-  int i;
-  int j;
-  stl_edge edge_a;
-  stl_edge edge_b;
-  int neighbor;
-  int vnot;
+void stl_verify_neighbors(stl_file *stl)
+{
+	if (stl->error)
+		return;
 
-  if (stl->error) return;
+	stl->stats.backwards_edges = 0;
 
-  stl->stats.backwards_edges = 0;
-
-  for(i = 0; i < stl->stats.number_of_facets; i++) {
-    for(j = 0; j < 3; j++) {
-      edge_a.p1 = stl->facet_start[i].vertex[j];
-      edge_a.p2 = stl->facet_start[i].vertex[(j + 1) % 3];
-      neighbor = stl->neighbors_start[i].neighbor[j];
-      vnot = stl->neighbors_start[i].which_vertex_not[j];
-
-      if(neighbor == -1)
-        continue;		/* this edge has no neighbor... Continue. */
-      if(vnot < 3) {
-        edge_b.p1 = stl->facet_start[neighbor].vertex[(vnot + 2) % 3];
-        edge_b.p2 = stl->facet_start[neighbor].vertex[(vnot + 1) % 3];
-      } else {
-        stl->stats.backwards_edges += 1;
-        edge_b.p1 = stl->facet_start[neighbor].vertex[(vnot + 1) % 3];
-        edge_b.p2 = stl->facet_start[neighbor].vertex[(vnot + 2) % 3];
-      }
-      if (edge_a.p1 != edge_b.p1 || edge_a.p2 != edge_b.p2) {
-        /* These edges should match but they don't.  Print results. */
-        printf("edge %d of facet %d doesn't match edge %d of facet %d\n",
-               j, i, vnot + 1, neighbor);
-        stl_write_facet(stl, (char*)"first facet", i);
-        stl_write_facet(stl, (char*)"second facet", neighbor);
-      }
-    }
-  }
+	for (uint32_t i = 0; i < stl->stats.number_of_facets; ++ i) {
+		for (int j = 0; j < 3; ++ j) {
+			stl_edge edge_a;
+			edge_a.p1 = stl->facet_start[i].vertex[j];
+			edge_a.p2 = stl->facet_start[i].vertex[(j + 1) % 3];
+			int neighbor = stl->neighbors_start[i].neighbor[j];
+			if (neighbor == -1)
+				continue; // this edge has no neighbor... Continue.
+			int vnot = stl->neighbors_start[i].which_vertex_not[j];
+			stl_edge edge_b;
+			if (vnot < 3) {
+				edge_b.p1 = stl->facet_start[neighbor].vertex[(vnot + 2) % 3];
+				edge_b.p2 = stl->facet_start[neighbor].vertex[(vnot + 1) % 3];
+			} else {
+				stl->stats.backwards_edges += 1;
+				edge_b.p1 = stl->facet_start[neighbor].vertex[(vnot + 1) % 3];
+				edge_b.p2 = stl->facet_start[neighbor].vertex[(vnot + 2) % 3];
+			}
+			if (edge_a.p1 != edge_b.p1 || edge_a.p2 != edge_b.p2) {
+				// These edges should match but they don't.  Print results.
+				printf("edge %d of facet %d doesn't match edge %d of facet %d\n", j, i, vnot + 1, neighbor);
+				stl_write_facet(stl, (char*)"first facet", i);
+				stl_write_facet(stl, (char*)"second facet", neighbor);
+			}
+		}
+	}
 }
 
 void stl_translate(stl_file *stl, float x, float y, float z)
@@ -263,21 +257,19 @@ void stl_mirror_yz(stl_file *stl)
 
 void stl_mirror_xz(stl_file *stl)
 {
-  if (stl->error)
-  	return;
+	if (stl->error)
+		return;
 
-  for (int i = 0; i < stl->stats.number_of_facets; i++) {
-    for (int j = 0; j < 3; j++) {
-      stl->facet_start[i].vertex[j](1) *= -1.0;
-    }
-  }
-  float temp_size = stl->stats.min(1);
-  stl->stats.min(1) = stl->stats.max(1);
-  stl->stats.max(1) = temp_size;
-  stl->stats.min(1) *= -1.0;
-  stl->stats.max(1) *= -1.0;
-  stl_reverse_all_facets(stl);
-  stl->stats.facets_reversed -= stl->stats.number_of_facets;  /* for not altering stats */
+	for (uint32_t i = 0; i < stl->stats.number_of_facets; ++ i)
+		for (int j = 0; j < 3; ++ j)
+			stl->facet_start[i].vertex[j](1) *= -1.0;
+	float temp_size = stl->stats.min(1);
+	stl->stats.min(1) = stl->stats.max(1);
+	stl->stats.max(1) = temp_size;
+	stl->stats.min(1) *= -1.0;
+	stl->stats.max(1) *= -1.0;
+	stl_reverse_all_facets(stl);
+	stl->stats.facets_reversed -= stl->stats.number_of_facets;  // for not altering stats
 }
 
 static float get_volume(stl_file *stl)
@@ -463,18 +455,18 @@ bool stl_validate(stl_file *stl)
 {
 	assert(! stl->error);
 	assert(stl->fp == nullptr);
-	assert(stl->facet_start != nullptr);
-	assert(stl->heads == nullptr);
+	assert(! stl->facet_start.empty());
+	assert(stl->heads.empty());
 	assert(stl->tail  == nullptr);
-	assert(stl->neighbors_start != nullptr);
-	assert((stl->v_indices == nullptr) == (stl->v_shared == nullptr));
+	assert(! stl->neighbors_start.empty());
+	assert((stl->v_indices.empty()) == (stl->v_shared.empty()));
 	assert(stl->stats.number_of_facets > 0);
 
 #ifdef _DEBUG
     // Verify validity of neighborship data.
     for (int facet_idx = 0; facet_idx < (int)stl->stats.number_of_facets; ++ facet_idx) {
         const stl_neighbors &nbr 		= stl->neighbors_start[facet_idx];
-        const int 			*vertices 	= (stl->v_indices == nullptr) ? nullptr : stl->v_indices[facet_idx].vertex;
+        const int 			*vertices 	= (stl->v_indices.empty()) ? nullptr : stl->v_indices[facet_idx].vertex;
         for (int nbr_idx = 0; nbr_idx < 3; ++ nbr_idx) {
             int nbr_face = stl->neighbors_start[facet_idx].neighbor[nbr_idx];
             assert(nbr_face < (int)stl->stats.number_of_facets);
diff --git a/src/libslic3r/Format/3mf.cpp b/src/libslic3r/Format/3mf.cpp
index 38b34c462..c3916a14e 100644
--- a/src/libslic3r/Format/3mf.cpp
+++ b/src/libslic3r/Format/3mf.cpp
@@ -1885,7 +1885,7 @@ namespace Slic3r {
                 volume->mesh.repair();
 
             stl_file& stl = volume->mesh.stl;
-            if (stl.v_shared == nullptr)
+            if (stl.v_shared.empty())
                 stl_generate_shared_vertices(&stl);
 
             if (stl.stats.shared_vertices == 0)
diff --git a/src/libslic3r/Format/AMF.cpp b/src/libslic3r/Format/AMF.cpp
index d26b5f3ed..f48b5b58c 100644
--- a/src/libslic3r/Format/AMF.cpp
+++ b/src/libslic3r/Format/AMF.cpp
@@ -926,7 +926,7 @@ bool store_amf(const char *path, Model *model, const DynamicPrintConfig *config)
             if (! volume->mesh.repaired) 
                 throw std::runtime_error("store_amf() requires repair()");
             auto &stl = volume->mesh.stl;
-            if (stl.v_shared == nullptr)
+            if (stl.v_shared.empty())
                 stl_generate_shared_vertices(&stl);
             const Transform3d& matrix = volume->get_matrix();
             for (size_t i = 0; i < stl.stats.shared_vertices; ++i) {
diff --git a/src/libslic3r/Format/PRUS.cpp b/src/libslic3r/Format/PRUS.cpp
index 502cac6e9..d983b1098 100644
--- a/src/libslic3r/Format/PRUS.cpp
+++ b/src/libslic3r/Format/PRUS.cpp
@@ -167,10 +167,10 @@ static void extract_model_from_archive(
             stl.stats.original_num_facets = header.nTriangles;
             stl_allocate(&stl);
             if (header.nTriangles > 0 && data.size() == 50 * header.nTriangles + sizeof(StlHeader)) {
-                memcpy((char*)stl.facet_start, data.data() + sizeof(StlHeader), 50 * header.nTriangles);
+                memcpy((char*)stl.facet_start.data(), data.data() + sizeof(StlHeader), 50 * header.nTriangles);
                 if (sizeof(stl_facet) > SIZEOF_STL_FACET) {
                     // The stl.facet_start is not packed tightly. Unpack the array of stl_facets.
-                    unsigned char *data = (unsigned char*)stl.facet_start;
+                    unsigned char *data = (unsigned char*)stl.facet_start.data();
                     for (size_t i = header.nTriangles - 1; i > 0; -- i)
                         memmove(data + i * sizeof(stl_facet), data + i * SIZEOF_STL_FACET, SIZEOF_STL_FACET);
                 }
@@ -257,7 +257,7 @@ static void extract_model_from_archive(
             stl.stats.number_of_facets = (uint32_t)facets.size();
             stl.stats.original_num_facets = (int)facets.size();
             stl_allocate(&stl);
-            memcpy((void*)stl.facet_start, facets.data(), facets.size() * 50);
+            memcpy((void*)stl.facet_start.data(), facets.data(), facets.size() * 50);
             stl_get_size(&stl);
             mesh.repair();
             // Add a mesh to a model.
diff --git a/src/libslic3r/Model.cpp b/src/libslic3r/Model.cpp
index 3b1bd5df2..64fbb9a2a 100644
--- a/src/libslic3r/Model.cpp
+++ b/src/libslic3r/Model.cpp
@@ -910,18 +910,16 @@ Polygon ModelObject::convex_hull_2d(const Transform3d &trafo_instance) const
         if (v->is_model_part()) {
             const stl_file &stl = v->mesh.stl;
             Transform3d trafo = trafo_instance * v->get_matrix();
-            if (stl.v_shared == nullptr) {
+            if (stl.v_shared.empty()) {
                 // Using the STL faces.
-                for (unsigned int i = 0; i < stl.stats.number_of_facets; ++ i) {
-                    const stl_facet &facet = stl.facet_start[i];
+				for (const stl_facet &facet : stl.facet_start)
                     for (size_t j = 0; j < 3; ++ j) {
                         Vec3d p = trafo * facet.vertex[j].cast<double>();
                         pts.emplace_back(coord_t(scale_(p.x())), coord_t(scale_(p.y())));
                     }
-                }
             } else {
                 // Using the shared vertices should be a bit quicker than using the STL faces.
-                for (int i = 0; i < stl.stats.shared_vertices; ++ i) {           
+                for (int i = 0; i < stl.stats.shared_vertices; ++ i) {
                     Vec3d p = trafo * stl.v_shared[i].cast<double>();
                     pts.emplace_back(coord_t(scale_(p.x())), coord_t(scale_(p.y())));
                 }
@@ -1347,13 +1345,9 @@ double ModelObject::get_instance_min_z(size_t instance_idx) const
 
         Transform3d mv = mi * v->get_matrix();
         const TriangleMesh& hull = v->get_convex_hull();
-        for (uint32_t f = 0; f < hull.stl.stats.number_of_facets; ++f)
-        {
-            const stl_facet* facet = hull.stl.facet_start + f;
-            min_z = std::min(min_z, Vec3d::UnitZ().dot(mv * facet->vertex[0].cast<double>()));
-            min_z = std::min(min_z, Vec3d::UnitZ().dot(mv * facet->vertex[1].cast<double>()));
-            min_z = std::min(min_z, Vec3d::UnitZ().dot(mv * facet->vertex[2].cast<double>()));
-        }
+		for (const stl_facet &facet : hull.stl.facet_start)
+			for (int i = 0; i < 3; ++ i)
+				min_z = std::min(min_z, (mv * facet.vertex[i].cast<double>()).z());
     }
 
     return min_z + inst->get_offset(Z);
diff --git a/src/libslic3r/SLA/SLASupportTreeIGL.cpp b/src/libslic3r/SLA/SLASupportTreeIGL.cpp
index c368b8604..1609b9ac4 100644
--- a/src/libslic3r/SLA/SLASupportTreeIGL.cpp
+++ b/src/libslic3r/SLA/SLASupportTreeIGL.cpp
@@ -121,19 +121,10 @@ EigenMesh3D::EigenMesh3D(const TriangleMesh& tmesh): m_aabb(new AABBImpl()) {
     V.resize(3*stl.stats.number_of_facets, 3);
     F.resize(stl.stats.number_of_facets, 3);
     for (unsigned int i = 0; i < stl.stats.number_of_facets; ++i) {
-        const stl_facet* facet = stl.facet_start+i;
-        V(3*i+0, 0) = double(facet->vertex[0](0));
-        V(3*i+0, 1) = double(facet->vertex[0](1));
-        V(3*i+0, 2) = double(facet->vertex[0](2));
-
-        V(3*i+1, 0) = double(facet->vertex[1](0));
-        V(3*i+1, 1) = double(facet->vertex[1](1));
-        V(3*i+1, 2) = double(facet->vertex[1](2));
-
-        V(3*i+2, 0) = double(facet->vertex[2](0));
-        V(3*i+2, 1) = double(facet->vertex[2](1));
-        V(3*i+2, 2) = double(facet->vertex[2](2));
-
+        const stl_facet &facet = stl.facet_start[i];
+		V.block<1, 3>(3 * i + 0, 0) = facet.vertex[0].cast<double>();
+		V.block<1, 3>(3 * i + 1, 0) = facet.vertex[1].cast<double>();
+		V.block<1, 3>(3 * i + 2, 0) = facet.vertex[2].cast<double>();
         F(i, 0) = int(3*i+0);
         F(i, 1) = int(3*i+1);
         F(i, 2) = int(3*i+2);
diff --git a/src/libslic3r/SlicingAdaptive.cpp b/src/libslic3r/SlicingAdaptive.cpp
index 2ef4aec8c..ad03b550b 100644
--- a/src/libslic3r/SlicingAdaptive.cpp
+++ b/src/libslic3r/SlicingAdaptive.cpp
@@ -27,8 +27,8 @@ void SlicingAdaptive::prepare()
 		nfaces_total += (*it_mesh)->stl.stats.number_of_facets;
 	m_faces.reserve(nfaces_total);
 	for (std::vector<const TriangleMesh*>::const_iterator it_mesh = m_meshes.begin(); it_mesh != m_meshes.end(); ++ it_mesh)
-		for (int i = 0; i < (*it_mesh)->stl.stats.number_of_facets; ++ i)
-			m_faces.push_back((*it_mesh)->stl.facet_start + i);
+		for (const stl_facet &face : (*it_mesh)->stl.facet_start)
+			m_faces.emplace_back(&face);
 
 	// 2) Sort faces lexicographically by their Z span.
 	std::sort(m_faces.begin(), m_faces.end(), [](const stl_facet *f1, const stl_facet *f2) {
diff --git a/src/libslic3r/TriangleMesh.cpp b/src/libslic3r/TriangleMesh.cpp
index b7c6c07a7..ac23abd26 100644
--- a/src/libslic3r/TriangleMesh.cpp
+++ b/src/libslic3r/TriangleMesh.cpp
@@ -51,7 +51,7 @@ TriangleMesh::TriangleMesh(const Pointf3s &points, const std::vector<Vec3crd>& f
     stl.stats.type = inmemory;
 
     // count facets and allocate memory
-    stl.stats.number_of_facets = facets.size();
+    stl.stats.number_of_facets = (uint32_t)facets.size();
     stl.stats.original_num_facets = stl.stats.number_of_facets;
     stl_allocate(&stl);
 
@@ -78,25 +78,14 @@ TriangleMesh& TriangleMesh::operator=(const TriangleMesh &other)
     stl_close(&this->stl);
     this->stl       = other.stl;
     this->repaired  = other.repaired;
-    this->stl.heads = nullptr;
+	this->stl.heads.clear();
     this->stl.tail  = nullptr;
     this->stl.error = other.stl.error;
-    if (other.stl.facet_start != nullptr) {
-        this->stl.facet_start = (stl_facet*)calloc(other.stl.stats.number_of_facets, sizeof(stl_facet));
-        std::copy(other.stl.facet_start, other.stl.facet_start + other.stl.stats.number_of_facets, this->stl.facet_start);
-    }
-    if (other.stl.neighbors_start != nullptr) {
-        this->stl.neighbors_start = (stl_neighbors*)calloc(other.stl.stats.number_of_facets, sizeof(stl_neighbors));
-        std::copy(other.stl.neighbors_start, other.stl.neighbors_start + other.stl.stats.number_of_facets, this->stl.neighbors_start);
-    }
-    if (other.stl.v_indices != nullptr) {
-        this->stl.v_indices = (v_indices_struct*)calloc(other.stl.stats.number_of_facets, sizeof(v_indices_struct));
-        std::copy(other.stl.v_indices, other.stl.v_indices + other.stl.stats.number_of_facets, this->stl.v_indices);
-    }
-    if (other.stl.v_shared != nullptr) {
-        this->stl.v_shared = (stl_vertex*)calloc(other.stl.stats.shared_vertices, sizeof(stl_vertex));
-        std::copy(other.stl.v_shared, other.stl.v_shared + other.stl.stats.shared_vertices, this->stl.v_shared);
-    }
+    this->stl.facet_start = other.stl.facet_start;
+    this->stl.neighbors_start = other.stl.neighbors_start;
+    this->stl.v_indices = other.stl.v_indices;
+	this->stl.v_shared = other.stl.v_shared;
+	this->stl.stats = other.stl.stats;
     return *this;
 }
 
@@ -125,8 +114,8 @@ void TriangleMesh::repair()
     
     // checking nearby
     //int last_edges_fixed = 0;
-	float tolerance = stl.stats.shortest_edge;
-    float increment = stl.stats.bounding_diameter / 10000.0;
+	float tolerance = (float)stl.stats.shortest_edge;
+	float increment = (float)stl.stats.bounding_diameter / 10000.0f;
     int iterations = 2;
     if (stl.stats.connected_facets_3_edge < (int)stl.stats.number_of_facets) {
         for (int i = 0; i < iterations; i++) {
@@ -444,7 +433,7 @@ TriangleMeshPtrs TriangleMesh::split() const
         TriangleMesh* mesh = new TriangleMesh;
         meshes.emplace_back(mesh);
         mesh->stl.stats.type = inmemory;
-        mesh->stl.stats.number_of_facets = facets.size();
+        mesh->stl.stats.number_of_facets = (uint32_t)facets.size();
         mesh->stl.stats.original_num_facets = mesh->stl.stats.number_of_facets;
         stl_clear_error(&mesh->stl);
         stl_allocate(&mesh->stl);
@@ -486,13 +475,12 @@ ExPolygons TriangleMesh::horizontal_projection() const
 {
     Polygons pp;
     pp.reserve(this->stl.stats.number_of_facets);
-    for (uint32_t i = 0; i < this->stl.stats.number_of_facets; ++ i) {
-        stl_facet* facet = &this->stl.facet_start[i];
+	for (const stl_facet &facet : this->stl.facet_start) {
         Polygon p;
         p.points.resize(3);
-        p.points[0] = Point::new_scale(facet->vertex[0](0), facet->vertex[0](1));
-        p.points[1] = Point::new_scale(facet->vertex[1](0), facet->vertex[1](1));
-        p.points[2] = Point::new_scale(facet->vertex[2](0), facet->vertex[2](1));
+        p.points[0] = Point::new_scale(facet.vertex[0](0), facet.vertex[0](1));
+        p.points[1] = Point::new_scale(facet.vertex[1](0), facet.vertex[1](1));
+        p.points[2] = Point::new_scale(facet.vertex[2](0), facet.vertex[2](1));
         p.make_counter_clockwise();  // do this after scaling, as winding order might change while doing that
         pp.emplace_back(p);
     }
@@ -526,17 +514,15 @@ BoundingBoxf3 TriangleMesh::bounding_box() const
 BoundingBoxf3 TriangleMesh::transformed_bounding_box(const Transform3d &trafo) const
 {
     BoundingBoxf3 bbox;
-    if (stl.v_shared == nullptr) {
+    if (stl.v_shared.empty()) {
         // Using the STL faces.
-        for (size_t i = 0; i < this->facets_count(); ++ i) {
-            const stl_facet &facet = this->stl.facet_start[i];
+		for (const stl_facet &facet : this->stl.facet_start)
             for (size_t j = 0; j < 3; ++ j)
                 bbox.merge(trafo * facet.vertex[j].cast<double>());
-        }
     } else {
         // Using the shared vertices should be a bit quicker than using the STL faces.
-        for (int i = 0; i < stl.stats.shared_vertices; ++ i)            
-            bbox.merge(trafo * this->stl.v_shared[i].cast<double>());
+		for (const stl_vertex &v : this->stl.v_shared)
+            bbox.merge(trafo * v.cast<double>());
     }
     return bbox;
 }
@@ -551,18 +537,12 @@ TriangleMesh TriangleMesh::convex_hull_3d() const
     std::vector<PointForQHull> src_vertices;
 
     // We will now fill the vector with input points for computation:
-    stl_facet* facet_ptr = stl.facet_start;
-    while (facet_ptr < stl.facet_start + stl.stats.number_of_facets)
-    {
-        for (int i = 0; i < 3; ++i)
-        {
-            const stl_vertex& v = facet_ptr->vertex[i];
+	for (const stl_facet &facet : stl.facet_start)
+        for (int i = 0; i < 3; ++ i) {
+            const stl_vertex& v = facet.vertex[i];
             src_vertices.emplace_back(v(0), v(1), v(2));
         }
 
-        facet_ptr += 1;
-    }
-
     // The qhull call:
     orgQhull::Qhull qhull;
     qhull.disableOutputStream(); // we want qhull to be quiet
@@ -606,7 +586,7 @@ void TriangleMesh::require_shared_vertices()
     assert(stl_validate(&this->stl));
     if (! this->repaired) 
         this->repair();
-    if (this->stl.v_shared == nullptr) {
+    if (this->stl.v_shared.empty()) {
         BOOST_LOG_TRIVIAL(trace) << "TriangleMeshSlicer::require_shared_vertices - stl_generate_shared_vertices";
         stl_generate_shared_vertices(&(this->stl));
     }
@@ -622,10 +602,9 @@ void TriangleMeshSlicer::init(const TriangleMesh *_mesh, throw_on_cancel_callbac
 
     throw_on_cancel();
     facets_edges.assign(_mesh->stl.stats.number_of_facets * 3, -1);
-    v_scaled_shared.assign(_mesh->stl.v_shared, _mesh->stl.v_shared + _mesh->stl.stats.shared_vertices);
-    // Scale the copied vertices.
-    for (int i = 0; i < this->mesh->stl.stats.shared_vertices; ++ i)
-        this->v_scaled_shared[i] *= float(1. / SCALING_FACTOR);
+	v_scaled_shared.assign(_mesh->stl.v_shared.size(), stl_vertex());
+	for (size_t i = 0; i < v_scaled_shared.size(); ++ i)
+        this->v_scaled_shared[i] = _mesh->stl.v_shared[i] / float(SCALING_FACTOR);
 
     // Create a mapping from triangle edge into face.
     struct EdgeToFace {
@@ -814,7 +793,7 @@ void TriangleMeshSlicer::slice(const std::vector<float> &z, std::vector<Polygons
 void TriangleMeshSlicer::_slice_do(size_t facet_idx, std::vector<IntersectionLines>* lines, boost::mutex* lines_mutex, 
     const std::vector<float> &z) const
 {
-    const stl_facet &facet = m_use_quaternion ? this->mesh->stl.facet_start[facet_idx].rotated(m_quaternion) : this->mesh->stl.facet_start[facet_idx];
+    const stl_facet &facet = m_use_quaternion ? (this->mesh->stl.facet_start.data() + facet_idx)->rotated(m_quaternion) : *(this->mesh->stl.facet_start.data() + facet_idx);
     
     // find facet extents
     const float min_z = fminf(facet.vertex[0](2), fminf(facet.vertex[1](2), facet.vertex[2](2)));
@@ -1710,7 +1689,7 @@ void TriangleMeshSlicer::cut(float z, TriangleMesh* upper, TriangleMesh* lower)
     BOOST_LOG_TRIVIAL(trace) << "TriangleMeshSlicer::cut - slicing object";
     float scaled_z = scale_(z);
     for (uint32_t facet_idx = 0; facet_idx < this->mesh->stl.stats.number_of_facets; ++ facet_idx) {
-        stl_facet* facet = &this->mesh->stl.facet_start[facet_idx];
+        const stl_facet* facet = &this->mesh->stl.facet_start[facet_idx];
         
         // find facet extents
         float min_z = std::min(facet->vertex[0](2), std::min(facet->vertex[1](2), facet->vertex[2](2)));
@@ -1901,10 +1880,10 @@ TriangleMesh make_cylinder(double r, double h, double fa)
 //FIXME better to discretize an Icosahedron recursively http://www.songho.ca/opengl/gl_sphere.html
 TriangleMesh make_sphere(double radius, double fa)
 {
-	int   sectorCount = ceil(2. * M_PI / fa);
-	int   stackCount  = ceil(M_PI / fa);
-	float sectorStep  = 2. * M_PI / sectorCount;
-	float stackStep   = M_PI / stackCount;
+	int   sectorCount = int(ceil(2. * M_PI / fa));
+	int   stackCount  = int(ceil(M_PI / fa));
+	float sectorStep  = float(2. * M_PI / sectorCount);
+	float stackStep   = float(M_PI / stackCount);
 
 	Pointf3s vertices;
 	vertices.reserve((stackCount - 1) * sectorCount + 2);
diff --git a/src/libslic3r/TriangleMesh.hpp b/src/libslic3r/TriangleMesh.hpp
index c284f6482..4de1f5989 100644
--- a/src/libslic3r/TriangleMesh.hpp
+++ b/src/libslic3r/TriangleMesh.hpp
@@ -58,7 +58,7 @@ public:
     TriangleMeshPtrs split() const;
     void merge(const TriangleMesh &mesh);
     ExPolygons horizontal_projection() const;
-    const float* first_vertex() const { return this->stl.facet_start ? &this->stl.facet_start->vertex[0](0) : nullptr; }
+    const float* first_vertex() const { return this->stl.facet_start.empty() ? nullptr : &this->stl.facet_start.front().vertex[0](0); }
     // 2D convex hull of a 3D mesh projected into the Z=0 plane.
     Polygon convex_hull();
     BoundingBoxf3 bounding_box() const;
@@ -69,7 +69,7 @@ public:
     void reset_repair_stats();
     bool needed_repair() const;
     void require_shared_vertices();
-    bool   has_shared_vertices() const { return stl.v_shared != NULL; }
+    bool   has_shared_vertices() const { return ! stl.v_shared.empty(); }
     size_t facets_count() const { return this->stl.stats.number_of_facets; }
     bool   empty() const { return this->facets_count() == 0; }
     bool is_splittable() const;
diff --git a/src/slic3r/GUI/Gizmos/GLGizmoSlaSupports.cpp b/src/slic3r/GUI/Gizmos/GLGizmoSlaSupports.cpp
index d118a6877..ae017f7d1 100644
--- a/src/slic3r/GUI/Gizmos/GLGizmoSlaSupports.cpp
+++ b/src/slic3r/GUI/Gizmos/GLGizmoSlaSupports.cpp
@@ -396,10 +396,10 @@ void GLGizmoSlaSupports::update_mesh()
     V.resize(3 * stl.stats.number_of_facets, 3);
     F.resize(stl.stats.number_of_facets, 3);
     for (unsigned int i=0; i<stl.stats.number_of_facets; ++i) {
-        const stl_facet* facet = stl.facet_start+i;
-        V(3*i+0, 0) = facet->vertex[0](0); V(3*i+0, 1) = facet->vertex[0](1); V(3*i+0, 2) = facet->vertex[0](2);
-        V(3*i+1, 0) = facet->vertex[1](0); V(3*i+1, 1) = facet->vertex[1](1); V(3*i+1, 2) = facet->vertex[1](2);
-        V(3*i+2, 0) = facet->vertex[2](0); V(3*i+2, 1) = facet->vertex[2](1); V(3*i+2, 2) = facet->vertex[2](2);
+        const stl_facet &facet = stl.facet_start[i];
+		V.block<1, 3>(3 * i + 0, 0) = facet.vertex[0];
+		V.block<1, 3>(3 * i + 1, 0) = facet.vertex[1];
+		V.block<1, 3>(3 * i + 2, 0) = facet.vertex[2];
         F(i, 0) = 3*i+0;
         F(i, 1) = 3*i+1;
         F(i, 2) = 3*i+2;