/* ADMesh -- process triangulated solid meshes
* Copyright (C) 1995, 1996 Anthony D. Martin <amartin@engr.csulb.edu>
* Copyright (C) 2013, 2014 several contributors, see AUTHORS
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Questions, comments, suggestions, etc to
* https://github.com/admesh/admesh/issues
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <algorithm>
#include <vector>
#include <boost/predef/other/endian.h>
#include <boost/log/trivial.hpp>
// Boost pool: Don't use mutexes to synchronize memory allocation.
#define BOOST_POOL_NO_MT
#include <boost/pool/object_pool.hpp>
#include "stl.h"
struct HashEdge {
// Key of a hash edge: sorted vertices of the edge.
uint32_t key[6];
// Compare two keys.
bool operator==(const HashEdge &rhs) const { return memcmp(key, rhs.key, sizeof(key)) == 0; }
bool operator!=(const HashEdge &rhs) const { 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;
HashEdge *next;
void load_exact(stl_file *stl, const stl_vertex *a, const stl_vertex *b)
{
{
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 (vertex_lower(*a, *b)) {
} else {
// This edge is loaded backwards.
std::swap(a, b);
this->which_edge += 3;
}
memcpy(&this->key[0], a->data(), sizeof(stl_vertex));
memcpy(&this->key[3], 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 = (unsigned char*)(this->key + i);
#if BOOST_ENDIAN_LITTLE_BYTE
if (p[0] == 0 && p[1] == 0 && p[2] == 0 && p[3] == 0x80)
// Negative zero, switch to positive zero.
p[3] = 0;
#else /* BOOST_ENDIAN_LITTLE_BYTE */
if (p[0] == 0x80 && p[1] == 0 && p[2] == 0 && p[3] == 0)
// Negative zero, switch to positive zero.
p[0] = 0;
#endif /* BOOST_ENDIAN_LITTLE_BYTE */
}
}
bool load_nearby(const stl_file *stl, const stl_vertex &a, const stl_vertex &b, float tolerance)
{
// Index of a grid cell spaced by tolerance.
typedef Eigen::Matrix<int32_t, 3, 1, Eigen::DontAlign> Vec3i;
Vec3i vertex1 = ((a - stl->stats.min) / tolerance).cast<int32_t>();
Vec3i vertex2 = ((b - stl->stats.min) / tolerance).cast<int32_t>();
static_assert(sizeof(Vec3i) == 12, "size of Vec3i incorrect");
if (vertex1 == vertex2)
// Both vertices hash to the same value
return false;
// Ensure identical vertex ordering of edges, which vertices land into equal grid cells.
// This method is numerically robust.
if ((vertex1[0] != vertex2[0]) ?
(vertex1[0] < vertex2[0]) :
((vertex1[1] != vertex2[1]) ?
(vertex1[1] < vertex2[1]) :
(vertex1[2] < vertex2[2]))) {
memcpy(&this->key[0], vertex1.data(), sizeof(stl_vertex));
memcpy(&this->key[3], vertex2.data(), sizeof(stl_vertex));
} else {
memcpy(&this->key[0], vertex2.data(), sizeof(stl_vertex));
memcpy(&this->key[3], vertex1.data(), sizeof(stl_vertex));
this->which_edge += 3; /* this edge is loaded backwards */
}
return true;
}
private:
inline bool vertex_lower(const stl_vertex &a, const stl_vertex &b) {
return (a(0) != b(0)) ? (a(0) < b(0)) :
((a(1) != b(1)) ? (a(1) < b(1)) : (a(2) < b(2)));
}
};
struct HashTableEdges {
HashTableEdges(size_t number_of_faces) {
this->M = (int)hash_size_from_nr_faces(number_of_faces);
this->heads.assign(this->M, nullptr);
this->tail = pool.construct();
this->tail->next = this->tail;
for (int i = 0; i < this->M; ++ i)
this->heads[i] = this->tail;
}
~HashTableEdges() {
#ifndef NDEBUG
for (int i = 0; i < this->M; ++ i)
for (HashEdge *temp = this->heads[i]; temp != this->tail; temp = temp->next)
++ this->freed;
this->tail = nullptr;
#endif /* NDEBUG */
}
void insert_edge_exact(stl_file *stl, const HashEdge &edge)
{
this->insert_edge(stl, edge, [stl](const HashEdge& edge1, const HashEdge& edge2) { record_neighbors(stl, edge1, edge2); });
}
void insert_edge_nearby(stl_file *stl, const HashEdge &edge)
{
this->insert_edge(stl, edge, [stl](const HashEdge& edge1, const HashEdge& edge2) { match_neighbors_nearby(stl, edge1, edge2); });
}
// Hash table on edges
std::vector<HashEdge*> heads;
HashEdge* tail;
int M;
boost::object_pool<HashEdge> pool;
#ifndef NDEBUG
size_t malloced = 0;
size_t freed = 0;
size_t collisions = 0;
#endif /* NDEBUG */
private:
static inline size_t hash_size_from_nr_faces(const size_t nr_faces)
{
// Good primes for addressing a cca. 30 bit space.
// https://planetmath.org/goodhashtableprimes
static std::vector<uint32_t> primes{ 98317, 196613, 393241, 786433, 1572869, 3145739, 6291469, 12582917, 25165843, 50331653, 100663319, 201326611, 402653189, 805306457, 1610612741 };
// Find a prime number for 50% filling of the shared triangle edges in the mesh.
auto it = std::upper_bound(primes.begin(), primes.end(), nr_faces * 3 * 2 - 1);
return (it == primes.end()) ? primes.back() : *it;
}
// MatchNeighbors(stl_file *stl, const HashEdge &edge_a, const HashEdge &edge_b)
template<typename MatchNeighbors>
void insert_edge(stl_file *stl, const HashEdge &edge, MatchNeighbors match_neighbors)
{
int chain_number = edge.hash(this->M);
HashEdge *link = this->heads[chain_number];
if (link == this->tail) {
// This list doesn't have any edges currently in it. Add this one.
HashEdge *new_edge = pool.construct(edge);
#ifndef NDEBUG
++ this->malloced;
#endif /* NDEBUG */
new_edge->next = this->tail;
this->heads[chain_number] = new_edge;
} else if (edges_equal(edge, *link)) {
// This is a match. Record result in neighbors list.
match_neighbors(edge, *link);
// Delete the matched edge from the list.
this->heads[chain_number] = link->next;
// pool.destroy(link);
#ifndef NDEBUG
++ this->freed;
#endif /* NDEBUG */
} else {
// Continue through the rest of the list.
for (;;) {
if (link->next == this->tail) {
// This is the last item in the list. Insert a new edge.
HashEdge *new_edge = pool.construct();
#ifndef NDEBUG
++ this->malloced;
#endif /* NDEBUG */
*new_edge = edge;
new_edge->next = this->tail;
link->next = new_edge;
#ifndef NDEBUG
++ this->collisions;
#endif /* NDEBUG */
break;
}
if (edges_equal(edge, *link->next)) {
// This is a match. Record result in neighbors list.
match_neighbors(edge, *link->next);
// Delete the matched edge from the list.
HashEdge *temp = link->next;
link->next = link->next->next;
// pool.destroy(temp);
#ifndef NDEBUG
++ this->freed;
#endif /* NDEBUG */
break;
}
// This is not a match. Go to the next link.
link = link->next;
#ifndef NDEBUG
++ this->collisions;
#endif /* NDEBUG */
}
}
}
// Edges equal for hashing. Edgesof different facet are allowed to be matched.
static inline bool edges_equal(const HashEdge &edge_a, const HashEdge &edge_b)
{
return edge_a.facet_number != edge_b.facet_number && edge_a == edge_b;
}
static void record_neighbors(stl_file *stl, const HashEdge &edge_a, const HashEdge &edge_b)
{
// 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 */
// 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 */
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;
}
// Count successful connects:
// Total connects:
stl->stats.connected_edges += 2;
// Count individual connects:
switch (stl->neighbors_start[edge_a.facet_number].num_neighbors()) {
case 1: ++ stl->stats.connected_facets_1_edge; break;
case 2: ++ stl->stats.connected_facets_2_edge; break;
case 3: ++ stl->stats.connected_facets_3_edge; break;
default: assert(false);
}
switch (stl->neighbors_start[edge_b.facet_number].num_neighbors()) {
case 1: ++ stl->stats.connected_facets_1_edge; break;
case 2: ++ stl->stats.connected_facets_2_edge; break;
case 3: ++ stl->stats.connected_facets_3_edge; break;
default: assert(false);
}
}
static void match_neighbors_nearby(stl_file *stl, const HashEdge &edge_a, const HashEdge &edge_b)
{
record_neighbors(stl, edge_a, edge_b);
// Which vertices to change
int facet1 = -1;
int facet2 = -1;
int vertex1, vertex2;
stl_vertex new_vertex1, new_vertex2;
{
int v1a; // pair 1, facet a
int v1b; // pair 1, facet b
int v2a; // pair 2, facet a
int v2b; // pair 2, facet b
// Find first pair.
if (edge_a.which_edge < 3) {
v1a = edge_a.which_edge;
v2a = (edge_a.which_edge + 1) % 3;
} else {
v2a = edge_a.which_edge % 3;
v1a = (edge_a.which_edge + 1) % 3;
}
if (edge_b.which_edge < 3) {
v1b = edge_b.which_edge;
v2b = (edge_b.which_edge + 1) % 3;
} else {
v2b = edge_b.which_edge % 3;
v1b = (edge_b.which_edge + 1) % 3;
}
// 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 different.
if ( (stl->neighbors_start[edge_a.facet_number].neighbor[v1a] == -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;
new_vertex1 = stl->facet_start[edge_b.facet_number].vertex[v1b];
} else {
facet1 = edge_b.facet_number;
vertex1 = v1b;
new_vertex1 = stl->facet_start[edge_a.facet_number].vertex[v1a];
}
}
// Of the second pair, which vertex, if any, should be changed.
if (stl->facet_start[edge_a.facet_number].vertex[v2a] == stl->facet_start[edge_b.facet_number].vertex[v2b]) {
// These facets are different.
if ( (stl->neighbors_start[edge_a.facet_number].neighbor[v2a] == -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;
new_vertex2 = stl->facet_start[edge_b.facet_number].vertex[v2b];
} else {
facet2 = edge_b.facet_number;
vertex2 = v2b;
new_vertex2 = stl->facet_start[edge_a.facet_number].vertex[v2a];
}
}
}
auto change_vertices = [stl](int facet_num, int vnot, stl_vertex new_vertex)
{
int first_facet = facet_num;
bool direction = false;
for (;;) {
int pivot_vertex;
int next_edge;
if (vnot > 2) {
if (direction) {
pivot_vertex = (vnot + 1) % 3;
next_edge = vnot % 3;
}
else {
pivot_vertex = (vnot + 2) % 3;
next_edge = pivot_vertex;
}
direction = !direction;
}
else {
if (direction) {
pivot_vertex = (vnot + 2) % 3;
next_edge = pivot_vertex;
}
else {
pivot_vertex = (vnot + 1) % 3;
next_edge = vnot;
}
}
#if 0
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(0), new_vertex(1), new_vertex(2));
else {
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](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](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](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;
vnot = stl->neighbors_start[facet_num].which_vertex_not[next_edge];
facet_num = stl->neighbors_start[facet_num].neighbor[next_edge];
if (facet_num == -1)
break;
if (facet_num == first_facet) {
// back to the beginning
BOOST_LOG_TRIVIAL(info) << "Back to the first facet changing vertices: probably a mobius part. Try using a smaller tolerance or don't do a nearby check.";
return;
}
}
};
if (facet1 != -1) {
int vnot1 = (facet1 == edge_a.facet_number) ?
(edge_a.which_edge + 2) % 3 :
(edge_b.which_edge + 2) % 3;
if (((vnot1 + 2) % 3) == vertex1)
vnot1 += 3;
change_vertices(facet1, vnot1, new_vertex1);
}
if (facet2 != -1) {
int vnot2 = (facet2 == edge_a.facet_number) ?
(edge_a.which_edge + 2) % 3 :
(edge_b.which_edge + 2) % 3;
if (((vnot2 + 2) % 3) == vertex2)
vnot2 += 3;
change_vertices(facet2, vnot2, new_vertex2);
}
stl->stats.edges_fixed += 2;
}
};
// This function builds the neighbors list. No modifications are made
// to any of the facets. The edges are said to match only if all six
// floats of the first edge matches all six floats of the second edge.
void stl_check_facets_exact(stl_file *stl)
{
assert(stl->facet_start.size() == stl->neighbors_start.size());
stl->stats.connected_edges = 0;
stl->stats.connected_facets_1_edge = 0;
stl->stats.connected_facets_2_edge = 0;
stl->stats.connected_facets_3_edge = 0;
// If any two of the three vertices are found to be exactally the same, call them degenerate and remove the facet.
// Do it before the next step, as the next step stores references to the face indices in the hash tables and removing a facet
// will break the references.
for (uint32_t i = 0; i < stl->stats.number_of_facets;) {
stl_facet &facet = stl->facet_start[i];
if (facet.vertex[0] == facet.vertex[1] || facet.vertex[1] == facet.vertex[2] || facet.vertex[0] == facet.vertex[2]) {
// Remove the degenerate facet.
facet = stl->facet_start[-- stl->stats.number_of_facets];
stl->facet_start.pop_back();
stl->neighbors_start.pop_back();
stl->stats.facets_removed += 1;
stl->stats.degenerate_facets += 1;
} else
++ i;
}
// Initialize hash table.
HashTableEdges hash_table(stl->stats.number_of_facets);
for (auto &neighbor : stl->neighbors_start)
neighbor.reset();
// Connect neighbor edges.
for (uint32_t i = 0; i < stl->stats.number_of_facets; ++ i) {
const stl_facet &facet = stl->facet_start[i];
for (int j = 0; j < 3; ++ j) {
HashEdge edge;
edge.facet_number = i;
edge.which_edge = j;
edge.load_exact(stl, &facet.vertex[j], &facet.vertex[(j + 1) % 3]);
hash_table.insert_edge_exact(stl, edge);
}
}
#if 0
printf("Number of faces: %d, number of manifold edges: %d, number of connected edges: %d, number of unconnected edges: %d\r\n",
stl->stats.number_of_facets, stl->stats.number_of_facets * 3,
stl->stats.connected_edges, stl->stats.number_of_facets * 3 - stl->stats.connected_edges);
#endif
}
void stl_check_facets_nearby(stl_file *stl, float tolerance)
{
if ( (stl->stats.connected_facets_1_edge == stl->stats.number_of_facets)
&& (stl->stats.connected_facets_2_edge == stl->stats.number_of_facets)
&& (stl->stats.connected_facets_3_edge == stl->stats.number_of_facets)) {
// No need to check any further. All facets are connected.
return;
}
HashTableEdges hash_table(stl->stats.number_of_facets);
for (uint32_t 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) {
HashEdge edge;
edge.facet_number = i;
edge.which_edge = j;
if (edge.load_nearby(stl, facet.vertex[j], facet.vertex[(j + 1) % 3], tolerance))
// Only insert edges that have different keys.
hash_table.insert_edge_nearby(stl, edge);
}
}
}
}
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().
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 a face, which was not the last one.
// 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) {
BOOST_LOG_TRIVIAL(info) << "in remove_facet: neighbor = " << other_face_idx << " numfacets = " << stl->stats.number_of_facets << " this is wrong";
return;
}
other_face_idx = facet_number;
}
}
stl->facet_start.pop_back();
stl->neighbors_start.pop_back();
};
auto remove_degenerate = [stl, remove_facet](int facet)
{
// Update statistics on face connectivity.
auto stl_update_connects_remove_1 = [stl](int facet_num) {
//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) && (neighbor[1] != -1))
stl_update_connects_remove_1(neighbor[1]);
if ((neighbor[1] == -1) && (neighbor[0] != -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(i);
// assert(stl_validate(stl));
} else
++ i;
if (stl->stats.connected_facets_1_edge < (int)stl->stats.number_of_facets) {
// remove completely unconnected facets
for (uint32_t i = 0; i < stl->stats.number_of_facets;)
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_facet(i);
assert(stl_validate(stl));
} else
++ i;
}
}
void stl_fill_holes(stl_file *stl)
{
// Insert all unconnected edges into hash list.
HashTableEdges hash_table(stl->stats.number_of_facets);
for (uint32_t i = 0; i < stl->stats.number_of_facets; ++ i) {
stl_facet facet = stl->facet_start[i];
for (int j = 0; j < 3; ++ j) {
if(stl->neighbors_start[i].neighbor[j] != -1)
continue;
HashEdge edge;
edge.facet_number = i;
edge.which_edge = j;
edge.load_exact(stl, &facet.vertex[j], &facet.vertex[(j + 1) % 3]);
hash_table.insert_edge_exact(stl, edge);
}
}
for (uint32_t i = 0; i < stl->stats.number_of_facets; ++ i) {
stl_facet facet = stl->facet_start[i];
int neighbors_initial[3] = { stl->neighbors_start[i].neighbor[0], stl->neighbors_start[i].neighbor[1], stl->neighbors_start[i].neighbor[2] };
int first_facet = i;
for (int j = 0; j < 3; ++ j) {
if (stl->neighbors_start[i].neighbor[j] != -1)
continue;
stl_facet new_facet;
new_facet.vertex[0] = facet.vertex[j];
new_facet.vertex[1] = facet.vertex[(j + 1) % 3];
bool direction = neighbors_initial[(j + 2) % 3] == -1;
int facet_num = i;
int vnot = (j + 2) % 3;
for (;;) {
int pivot_vertex = 0;
int next_edge = 0;
if (vnot > 2) {
if (direction) {
pivot_vertex = (vnot + 1) % 3;
next_edge = vnot % 3;
} else {
pivot_vertex = (vnot + 2) % 3;
next_edge = pivot_vertex;
}
direction = ! direction;
} else {
if(direction == 0) {
pivot_vertex = (vnot + 1) % 3;
next_edge = vnot;
} else {
pivot_vertex = (vnot + 2) % 3;
next_edge = pivot_vertex;
}
}
int next_facet = stl->neighbors_start[facet_num].neighbor[next_edge];
if (next_facet == -1) {
new_facet.vertex[2] = stl->facet_start[facet_num].vertex[vnot % 3];
stl_add_facet(stl, &new_facet);
for (int k = 0; k < 3; ++ k) {
HashEdge edge;
edge.facet_number = stl->stats.number_of_facets - 1;
edge.which_edge = k;
edge.load_exact(stl, &new_facet.vertex[k], &new_facet.vertex[(k + 1) % 3]);
hash_table.insert_edge_exact(stl, edge);
}
break;
}
vnot = stl->neighbors_start[facet_num].which_vertex_not[next_edge];
facet_num = next_facet;
if (facet_num == first_facet) {
// back to the beginning
BOOST_LOG_TRIVIAL(info) << "Back to the first facet filling holes: probably a mobius part. Try using a smaller tolerance or don't do a nearby check.";
return;
}
}
}
}
}
void stl_add_facet(stl_file *stl, const stl_facet *new_facet)
{
assert(stl->facet_start.size() == stl->stats.number_of_facets);
assert(stl->neighbors_start.size() == 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();
++ stl->stats.facets_added;
++ stl->stats.number_of_facets;
}