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bubnikv 2018-08-22 15:03:35 +02:00
parent ac72cd779f
commit 6829704475
16 changed files with 539 additions and 908 deletions
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333
xs/src/admesh/connect.cpp
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@ -25,11 +25,11 @@
#include <string.h>
#include <math.h>
#include <boost/detail/endian.hpp>
#include "stl.h"
static void stl_match_neighbors_exact(stl_file *stl,
stl_hash_edge *edge_a, stl_hash_edge *edge_b);
static void stl_match_neighbors_nearby(stl_file *stl,
stl_hash_edge *edge_a, stl_hash_edge *edge_b);
static void stl_record_neighbors(stl_file *stl,
@ -43,7 +43,6 @@ static int stl_load_edge_nearby(stl_file *stl, stl_hash_edge *edge,
static void insert_hash_edge(stl_file *stl, stl_hash_edge edge,
void (*match_neighbors)(stl_file *stl,
stl_hash_edge *edge_a, stl_hash_edge *edge_b));
static int stl_get_hash_for_edge(int M, stl_hash_edge *edge);
static int stl_compare_function(stl_hash_edge *edge_a, stl_hash_edge *edge_b);
static void stl_free_edges(stl_file *stl);
static void stl_remove_facet(stl_file *stl, int facet_number);
@ -82,37 +81,20 @@ stl_check_facets_exact(stl_file *stl) {
for(i = 0; i < stl->stats.number_of_facets; i++) {
facet = stl->facet_start[i];
// Positive and negative zeros are possible in the floats, which are considered equal by the FP unit.
// When using a memcmp on raw floats, those numbers report to be different.
// Unify all +0 and -0 to +0 to make the floats equal under memcmp.
{
uint32_t *f = (uint32_t*)&facet;
for (int j = 0; j < 12; ++ j, ++ f) // 3x vertex + normal: 4x3 = 12 floats
if (*f == 0x80000000)
// Negative zero, switch to positive zero.
*f = 0;
}
/* If any two of the three vertices are found to be exactally the same, call them degenerate and remove the facet. */
if( !memcmp(&facet.vertex[0], &facet.vertex[1],
sizeof(stl_vertex))
|| !memcmp(&facet.vertex[1], &facet.vertex[2],
sizeof(stl_vertex))
|| !memcmp(&facet.vertex[0], &facet.vertex[2],
sizeof(stl_vertex))) {
// If any two of the three vertices are found to be exactally the same, call them degenerate and remove the facet.
if (facet.vertex[0] == facet.vertex[1] ||
facet.vertex[1] == facet.vertex[2] ||
facet.vertex[0] == facet.vertex[2]) {
stl->stats.degenerate_facets += 1;
stl_remove_facet(stl, i);
i--;
-- i;
continue;
}
for(j = 0; j < 3; j++) {
edge.facet_number = i;
edge.which_edge = j;
stl_load_edge_exact(stl, &edge, &facet.vertex[j],
&facet.vertex[(j + 1) % 3]);
insert_hash_edge(stl, edge, stl_match_neighbors_exact);
stl_load_edge_exact(stl, &edge, &facet.vertex[j], &facet.vertex[(j + 1) % 3]);
insert_hash_edge(stl, edge, stl_record_neighbors);
}
}
stl_free_edges(stl);
@ -131,28 +113,33 @@ stl_load_edge_exact(stl_file *stl, stl_hash_edge *edge,
if (stl->error) return;
{
float diff_x = ABS(a->x - b->x);
float diff_y = ABS(a->y - b->y);
float diff_z = ABS(a->z - b->z);
float max_diff = STL_MAX(diff_x, diff_y);
max_diff = STL_MAX(diff_z, max_diff);
stl->stats.shortest_edge = STL_MIN(max_diff, stl->stats.shortest_edge);
stl_vertex diff = (*a - *b).cwiseAbs();
float max_diff = std::max(diff(0), std::max(diff(1), diff(2)));
stl->stats.shortest_edge = std::min(max_diff, stl->stats.shortest_edge);
}
// Ensure identical vertex ordering of equal edges.
// This method is numerically robust.
if ((a->x != b->x) ?
(a->x < b->x) :
((a->y != b->y) ?
(a->y < b->y) :
(a->z < b->z))) {
memcpy(&edge->key[0], a, sizeof(stl_vertex));
memcpy(&edge->key[3], b, sizeof(stl_vertex));
if (stl_vertex_lower(*a, *b)) {
} else {
memcpy(&edge->key[0], b, sizeof(stl_vertex));
memcpy(&edge->key[3], a, sizeof(stl_vertex));
std::swap(a, b);
edge->which_edge += 3; /* this edge is loaded backwards */
}
memcpy(&edge->key[0], a->data(), sizeof(stl_vertex));
memcpy(&edge->key[sizeof(stl_vertex)], b->data(), sizeof(stl_vertex));
// Switch negative zeros to positive zeros, so memcmp will consider them to be equal.
for (size_t i = 0; i < 6; ++ i) {
unsigned char *p = edge->key + i * 4;
#ifdef BOOST_LITTLE_ENDIAN
if (p[0] == 0 && p[1] == 0 && p[2] == 0 && p[3] == 0x80)
// Negative zero, switch to positive zero.
p[3] = 0;
#else /* BOOST_LITTLE_ENDIAN */
if (p[0] == 0x80 && p[1] == 0 && p[2] == 0 && p[3] == 0)
// Negative zero, switch to positive zero.
p[0] = 0;
#endif /* BOOST_LITTLE_ENDIAN */
}
}
static void
@ -188,21 +175,17 @@ stl_initialize_facet_check_exact(stl_file *stl) {
}
}
static void
insert_hash_edge(stl_file *stl, stl_hash_edge edge,
static void insert_hash_edge(stl_file *stl, stl_hash_edge edge,
void (*match_neighbors)(stl_file *stl,
stl_hash_edge *edge_a, stl_hash_edge *edge_b)) {
stl_hash_edge *link;
stl_hash_edge *new_edge;
stl_hash_edge *temp;
int chain_number;
stl_hash_edge *edge_a, stl_hash_edge *edge_b))
{
if (stl->error) return;
chain_number = stl_get_hash_for_edge(stl->M, &edge);
link = stl->heads[chain_number];
int chain_number = edge.hash(stl->M);
stl_hash_edge *link = stl->heads[chain_number];
stl_hash_edge *new_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));
@ -252,30 +235,17 @@ insert_hash_edge(stl_file *stl, stl_hash_edge edge,
}
}
static int
stl_get_hash_for_edge(int M, stl_hash_edge *edge) {
return ((edge->key[0] / 23 + edge->key[1] / 19 + edge->key[2] / 17
+ edge->key[3] /13 + edge->key[4] / 11 + edge->key[5] / 7 ) % M);
// Return 1 if the edges are not matched.
static inline int stl_compare_function(stl_hash_edge *edge_a, stl_hash_edge *edge_b)
{
// Don't match edges of the same facet
return (edge_a->facet_number == edge_b->facet_number) || (*edge_a != *edge_b);
}
static int
stl_compare_function(stl_hash_edge *edge_a, stl_hash_edge *edge_b) {
if(edge_a->facet_number == edge_b->facet_number) {
return 1; /* Don't match edges of the same facet */
} else {
return memcmp(edge_a, edge_b, SIZEOF_EDGE_SORT);
}
}
void
stl_check_facets_nearby(stl_file *stl, float tolerance) {
stl_hash_edge edge[3];
stl_facet facet;
int i;
int j;
if (stl->error) return;
void stl_check_facets_nearby(stl_file *stl, float tolerance)
{
if (stl->error)
return;
if( (stl->stats.connected_facets_1_edge == stl->stats.number_of_facets)
&& (stl->stats.connected_facets_2_edge == stl->stats.number_of_facets)
@ -286,27 +256,19 @@ stl_check_facets_nearby(stl_file *stl, float tolerance) {
stl_initialize_facet_check_nearby(stl);
for(i = 0; i < stl->stats.number_of_facets; i++) {
facet = stl->facet_start[i];
// Positive and negative zeros are possible in the floats, which are considered equal by the FP unit.
// When using a memcmp on raw floats, those numbers report to be different.
// Unify all +0 and -0 to +0 to make the floats equal under memcmp.
{
uint32_t *f = (uint32_t*)&facet;
for (int j = 0; j < 12; ++ j, ++ f) // 3x vertex + normal: 4x3 = 12 floats
if (*f == 0x80000000)
// Negative zero, switch to positive zero.
*f = 0;
}
for(j = 0; j < 3; j++) {
for (int i = 0; i < stl->stats.number_of_facets; ++ i) {
//FIXME is the copy necessary?
stl_facet facet = stl->facet_start[i];
for (int j = 0; j < 3; j++) {
if(stl->neighbors_start[i].neighbor[j] == -1) {
edge[j].facet_number = i;
edge[j].which_edge = j;
if(stl_load_edge_nearby(stl, &edge[j], &facet.vertex[j],
stl_hash_edge edge;
edge.facet_number = i;
edge.which_edge = j;
if(stl_load_edge_nearby(stl, &edge, &facet.vertex[j],
&facet.vertex[(j + 1) % 3],
tolerance)) {
/* only insert edges that have different keys */
insert_hash_edge(stl, edge[j], stl_match_neighbors_nearby);
insert_hash_edge(stl, edge, stl_match_neighbors_nearby);
}
}
}
@ -315,27 +277,17 @@ stl_check_facets_nearby(stl_file *stl, float tolerance) {
stl_free_edges(stl);
}
static int
stl_load_edge_nearby(stl_file *stl, stl_hash_edge *edge,
stl_vertex *a, stl_vertex *b, float tolerance) {
static int stl_load_edge_nearby(stl_file *stl, stl_hash_edge *edge, stl_vertex *a, stl_vertex *b, float tolerance)
{
// Index of a grid cell spaced by tolerance.
uint32_t vertex1[3] = {
(uint32_t)((a->x - stl->stats.min.x) / tolerance),
(uint32_t)((a->y - stl->stats.min.y) / tolerance),
(uint32_t)((a->z - stl->stats.min.z) / tolerance)
};
uint32_t vertex2[3] = {
(uint32_t)((b->x - stl->stats.min.x) / tolerance),
(uint32_t)((b->y - stl->stats.min.y) / tolerance),
(uint32_t)((b->z - stl->stats.min.z) / tolerance)
};
typedef Eigen::Matrix<int32_t, 3, 1, Eigen::DontAlign> Vec3i;
Vec3i vertex1 = (*a / tolerance).cast<int32_t>();
Vec3i vertex2 = (*b / tolerance).cast<int32_t>();
static_assert(sizeof(Vec3i) == 12, "size of Vec3i incorrect");
if( (vertex1[0] == vertex2[0])
&& (vertex1[1] == vertex2[1])
&& (vertex1[2] == vertex2[2])) {
/* Both vertices hash to the same value */
if (vertex1 == vertex2)
// Both vertices hash to the same value
return 0;
}
// Ensure identical vertex ordering of edges, which vertices land into equal grid cells.
// This method is numerically robust.
@ -344,30 +296,27 @@ stl_load_edge_nearby(stl_file *stl, stl_hash_edge *edge,
((vertex1[1] != vertex2[1]) ?
(vertex1[1] < vertex2[1]) :
(vertex1[2] < vertex2[2]))) {
memcpy(&edge->key[0], vertex1, sizeof(stl_vertex));
memcpy(&edge->key[3], vertex2, sizeof(stl_vertex));
memcpy(&edge->key[0], vertex1.data(), sizeof(stl_vertex));
memcpy(&edge->key[sizeof(stl_vertex)], vertex2.data(), sizeof(stl_vertex));
} else {
memcpy(&edge->key[0], vertex2, sizeof(stl_vertex));
memcpy(&edge->key[3], vertex1, sizeof(stl_vertex));
memcpy(&edge->key[0], vertex2.data(), sizeof(stl_vertex));
memcpy(&edge->key[sizeof(stl_vertex)], vertex1.data(), sizeof(stl_vertex));
edge->which_edge += 3; /* this edge is loaded backwards */
}
return 1;
}
static void
stl_free_edges(stl_file *stl) {
int i;
stl_hash_edge *temp;
if (stl->error) return;
static void stl_free_edges(stl_file *stl)
{
if (stl->error)
return;
if(stl->stats.malloced != stl->stats.freed) {
for(i = 0; i < stl->M; i++) {
for(temp = stl->heads[i]; stl->heads[i] != stl->tail;
temp = stl->heads[i]) {
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);
stl->stats.freed++;
++ stl->stats.freed;
}
}
}
@ -375,8 +324,8 @@ stl_free_edges(stl_file *stl) {
free(stl->tail);
}
static void
stl_initialize_facet_check_nearby(stl_file *stl) {
static void stl_initialize_facet_check_nearby(stl_file *stl)
{
int i;
if (stl->error) return;
@ -467,16 +416,8 @@ stl_record_neighbors(stl_file *stl,
}
}
static void
stl_match_neighbors_exact(stl_file *stl,
stl_hash_edge *edge_a, stl_hash_edge *edge_b) {
if (stl->error) return;
stl_record_neighbors(stl, edge_a, edge_b);
}
static void
stl_match_neighbors_nearby(stl_file *stl,
stl_hash_edge *edge_a, stl_hash_edge *edge_b) {
static void stl_match_neighbors_nearby(stl_file *stl, stl_hash_edge *edge_a, stl_hash_edge *edge_b)
{
int facet1;
int facet2;
int vertex1;
@ -517,9 +458,7 @@ stl_match_neighbors_nearby(stl_file *stl,
}
static void
stl_change_vertices(stl_file *stl, int facet_num, int vnot,
stl_vertex new_vertex) {
static void stl_change_vertices(stl_file *stl, int facet_num, int vnot, stl_vertex new_vertex) {
int first_facet;
int direction;
int next_edge;
@ -551,30 +490,30 @@ stl_change_vertices(stl_file *stl, int facet_num, int vnot,
}
}
#if 0
if (stl->facet_start[facet_num].vertex[pivot_vertex].x == new_vertex.x &&
stl->facet_start[facet_num].vertex[pivot_vertex].y == new_vertex.y &&
stl->facet_start[facet_num].vertex[pivot_vertex].z == new_vertex.z)
if (stl->facet_start[facet_num].vertex[pivot_vertex](0) == new_vertex(0) &&
stl->facet_start[facet_num].vertex[pivot_vertex](1) == new_vertex(1) &&
stl->facet_start[facet_num].vertex[pivot_vertex](2) == new_vertex(2))
printf("Changing vertex %f,%f,%f: Same !!!\r\n",
new_vertex.x, new_vertex.y, new_vertex.z);
new_vertex(0), new_vertex(1), new_vertex(2));
else {
if (stl->facet_start[facet_num].vertex[pivot_vertex].x != new_vertex.x)
if (stl->facet_start[facet_num].vertex[pivot_vertex](0) != new_vertex(0))
printf("Changing coordinate x, vertex %e (0x%08x) to %e(0x%08x)\r\n",
stl->facet_start[facet_num].vertex[pivot_vertex].x,
*reinterpret_cast<const int*>(&stl->facet_start[facet_num].vertex[pivot_vertex].x),
new_vertex.x,
*reinterpret_cast<const int*>(&new_vertex.x));
if (stl->facet_start[facet_num].vertex[pivot_vertex].y != new_vertex.y)
stl->facet_start[facet_num].vertex[pivot_vertex](0),
*reinterpret_cast<const int*>(&stl->facet_start[facet_num].vertex[pivot_vertex](0)),
new_vertex(0),
*reinterpret_cast<const int*>(&new_vertex(0)));
if (stl->facet_start[facet_num].vertex[pivot_vertex](1) != new_vertex(1))
printf("Changing coordinate x, vertex %e (0x%08x) to %e(0x%08x)\r\n",
stl->facet_start[facet_num].vertex[pivot_vertex].y,
*reinterpret_cast<const int*>(&stl->facet_start[facet_num].vertex[pivot_vertex].y),
new_vertex.y,
*reinterpret_cast<const int*>(&new_vertex.y));
if (stl->facet_start[facet_num].vertex[pivot_vertex].z != new_vertex.z)
stl->facet_start[facet_num].vertex[pivot_vertex](1),
*reinterpret_cast<const int*>(&stl->facet_start[facet_num].vertex[pivot_vertex](1)),
new_vertex(1),
*reinterpret_cast<const int*>(&new_vertex(1)));
if (stl->facet_start[facet_num].vertex[pivot_vertex](2) != new_vertex(2))
printf("Changing coordinate x, vertex %e (0x%08x) to %e(0x%08x)\r\n",
stl->facet_start[facet_num].vertex[pivot_vertex].z,
*reinterpret_cast<const int*>(&stl->facet_start[facet_num].vertex[pivot_vertex].z),
new_vertex.z,
*reinterpret_cast<const int*>(&new_vertex.z));
stl->facet_start[facet_num].vertex[pivot_vertex](2),
*reinterpret_cast<const int*>(&stl->facet_start[facet_num].vertex[pivot_vertex](2)),
new_vertex(2),
*reinterpret_cast<const int*>(&new_vertex(2)));
}
#endif
stl->facet_start[facet_num].vertex[pivot_vertex] = new_vertex;
@ -595,7 +534,6 @@ Try using a smaller tolerance or don't do a nearby check\n");
}
}
static void
stl_which_vertices_to_change(stl_file *stl, stl_hash_edge *edge_a,
stl_hash_edge *edge_b, int *facet1, int *vertex1,
@ -622,11 +560,10 @@ stl_which_vertices_to_change(stl_file *stl, stl_hash_edge *edge_a,
v1b = (edge_b->which_edge + 1) % 3;
}
/* Of the first pair, which vertex, if any, should be changed */
if(!memcmp(&stl->facet_start[edge_a->facet_number].vertex[v1a],
&stl->facet_start[edge_b->facet_number].vertex[v1b],
sizeof(stl_vertex))) {
/* These facets are already equal. No need to change. */
// Of the first pair, which vertex, if any, should be changed
if(stl->facet_start[edge_a->facet_number].vertex[v1a] ==
stl->facet_start[edge_b->facet_number].vertex[v1b]) {
// These facets are already equal. No need to change.
*facet1 = -1;
} else {
if( (stl->neighbors_start[edge_a->facet_number].neighbor[v1a] == -1)
@ -644,10 +581,9 @@ stl_which_vertices_to_change(stl_file *stl, stl_hash_edge *edge_a,
}
/* Of the second pair, which vertex, if any, should be changed */
if(!memcmp(&stl->facet_start[edge_a->facet_number].vertex[v2a],
&stl->facet_start[edge_b->facet_number].vertex[v2b],
sizeof(stl_vertex))) {
/* These facets are already equal. No need to change. */
if(stl->facet_start[edge_a->facet_number].vertex[v2a] ==
stl->facet_start[edge_b->facet_number].vertex[v2b]) {
// These facets are already equal. No need to change.
*facet2 = -1;
} else {
if( (stl->neighbors_start[edge_a->facet_number].neighbor[v2a] == -1)
@ -718,40 +654,35 @@ in stl_remove_facet: neighbor = %d numfacets = %d this is wrong\n",
}
}
void
stl_remove_unconnected_facets(stl_file *stl) {
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 */
/* useless and could be completely wrong. The second thing that needs to */
/* be done is to remove any degenerate facets that were created during */
/* stl_check_facets_nearby(). */
if (stl->error)
return;
int i;
if (stl->error) return;
/* remove degenerate facets */
for(i = 0; i < stl->stats.number_of_facets; i++) {
if( !memcmp(&stl->facet_start[i].vertex[0],
&stl->facet_start[i].vertex[1], sizeof(stl_vertex))
|| !memcmp(&stl->facet_start[i].vertex[1],
&stl->facet_start[i].vertex[2], sizeof(stl_vertex))
|| !memcmp(&stl->facet_start[i].vertex[0],
&stl->facet_start[i].vertex[2], sizeof(stl_vertex))) {
// remove degenerate facets
for (int i = 0; i < stl->stats.number_of_facets; ++ i) {
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]) {
stl_remove_degenerate(stl, i);
i--;
}
}
if(stl->stats.connected_facets_1_edge < stl->stats.number_of_facets) {
/* remove completely unconnected facets */
for(i = 0; i < stl->stats.number_of_facets; i++) {
if( (stl->neighbors_start[i].neighbor[0] == -1)
&& (stl->neighbors_start[i].neighbor[1] == -1)
&& (stl->neighbors_start[i].neighbor[2] == -1)) {
/* This facet is completely unconnected. Remove it. */
// remove completely unconnected facets
for (int i = 0; i < stl->stats.number_of_facets; i++) {
if (stl->neighbors_start[i].neighbor[0] == -1 &&
stl->neighbors_start[i].neighbor[1] == -1 &&
stl->neighbors_start[i].neighbor[2] == -1) {
// This facet is completely unconnected. Remove it.
stl_remove_facet(stl, i);
i--;
-- i;
}
}
}
@ -771,30 +702,24 @@ stl_remove_degenerate(stl_file *stl, int facet) {
if (stl->error) return;
if( !memcmp(&stl->facet_start[facet].vertex[0],
&stl->facet_start[facet].vertex[1], sizeof(stl_vertex))
&& !memcmp(&stl->facet_start[facet].vertex[1],
&stl->facet_start[facet].vertex[2], sizeof(stl_vertex))) {
if (stl->facet_start[facet].vertex[0] == stl->facet_start[facet].vertex[1] &&
stl->facet_start[facet].vertex[1] == stl->facet_start[facet].vertex[2]) {
/* all 3 vertices are equal. Just remove the facet. I don't think*/
/* this is really possible, but just in case... */
printf("removing a facet in stl_remove_degenerate\n");
stl_remove_facet(stl, facet);
return;
}
if(!memcmp(&stl->facet_start[facet].vertex[0],
&stl->facet_start[facet].vertex[1], sizeof(stl_vertex))) {
if (stl->facet_start[facet].vertex[0] == stl->facet_start[facet].vertex[1]) {
edge1 = 1;
edge2 = 2;
edge3 = 0;
} else if(!memcmp(&stl->facet_start[facet].vertex[1],
&stl->facet_start[facet].vertex[2], sizeof(stl_vertex))) {
} else if (stl->facet_start[facet].vertex[1] == stl->facet_start[facet].vertex[2]) {
edge1 = 0;
edge2 = 2;
edge3 = 1;
} else if(!memcmp(&stl->facet_start[facet].vertex[2],
&stl->facet_start[facet].vertex[0], sizeof(stl_vertex))) {
} else if (stl->facet_start[facet].vertex[2] == stl->facet_start[facet].vertex[0]) {
edge1 = 0;
edge2 = 1;
edge3 = 2;
@ -883,7 +808,7 @@ stl_fill_holes(stl_file *stl) {
stl_load_edge_exact(stl, &edge, &facet.vertex[j],
&facet.vertex[(j + 1) % 3]);
insert_hash_edge(stl, edge, stl_match_neighbors_exact);
insert_hash_edge(stl, edge, stl_record_neighbors);
}
}
@ -939,7 +864,7 @@ stl_fill_holes(stl_file *stl) {
stl_load_edge_exact(stl, &edge, &new_facet.vertex[k],
&new_facet.vertex[(k + 1) % 3]);
insert_hash_edge(stl, edge, stl_match_neighbors_exact);
insert_hash_edge(stl, edge, stl_record_neighbors);
}
break;
} else {
@ -977,9 +902,7 @@ stl_add_facet(stl_file *stl, stl_facet *new_facet) {
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.x = 0.0;
stl->facet_start[stl->stats.number_of_facets].normal.y = 0.0;
stl->facet_start[stl->stats.number_of_facets].normal.z = 0.0;
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;