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simplification.cpp
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simplification.cpp
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// This file is part of the implementation of
// Robust Structure Simplification for Hex Re-meshing
// Xifeng Gao, Daniele Panozzo, Wenping Wang, Zhigang Deng, Guoning Chen
// In ACM Transactions on Graphics (Proceedings of SIGGRAPH ASIA 2017)
//
// Copyright (C) 2017 Xifeng Gao<[email protected]>
//
// This Source Code Form is subject to the terms of the Mozilla Public License
// v. 2.0. If a copy of the MPL was not distributed with this file, You can
// obtain one at http://mozilla.org/MPL/2.0/.
#include "simplification.h"
#include "timer.h"
void simplification::pipeline() {
vector<unsigned long long> timings;
timings.push_back(0);
unsigned long long timer0, timer1, timer2, timer3, timer4;
timer0 = timer1 = timer2 = timer3 = timer4 = 0;
Timer<> timer;
timer.beginStage("looping");
uint32_t removed_candidates = 0;
Mesh_Quality mq;
while (true) {
Timer<> timer0_, timer1_, timer2_, timer3_, timer4_;
scaled_jacobian(mesh, mq);
if (mq.min_Jacobian < Jacobian_Bound) break;
cout << "to remove " << removed_candidates + 1 << endl;
//stopping criterions
if (Remove_Iteration != 0 && removed_candidates >= Remove_Iteration) break;
if (remove_cuboid_ratio != 0 && (double)(cuboid_num_original - frame.FHs.size()) / cuboid_num_original >= remove_cuboid_ratio) break;
if (!remove()) {
break; }
timer.endStage("end removing");
timer0 = timer.value();
timings.push_back(timer0);
extract();
ranking();
subdivision();
double remove_cs_ratio = (double)(cuboid_num_original - frame.FHs.size()) / cuboid_num_original;
removed_candidates++;
}
scaled_jacobian(mesh, mq);
cout << "minimum scaled J: " << mq.min_Jacobian << " average scaled J: " << mq.ave_Jacobian << endl;
std::cout << "B_V B_E B_F B_H: " << frame.FVs.size() << " " << frame.FEs.size() << " " << frame.FFs.size() << " " << frame.FHs.size() << endl;
std::cout << "#sheets removed: " << (double)(sheet_num_original - All_Sheets.size()) << endl;
std::cout << "Removed Component Ratio: " << (double)(cuboid_num_original - frame.FHs.size()) / cuboid_num_original << endl;
char path[300];
optimization();
sprintf(path, "%s%s", path_out, "_simplified_opt.vtk");
io.write_hybrid_mesh_VTK(mesh, path);
cout << "Structure Simplification Finished!" << endl;
timer.endStage("end Looping");
std::cout << "timing: " << timer.value()<<"ms"<< endl;
}
bool simplification::initialize() {
//topology information
topology_info(mesh, frame, mt);
if (mt.manifoldness_problem) {
cout << "non-manifold input, please double-check!" << endl; return false;
}
else {
cout << "surface euler: " << mt.surface_euler << endl;
cout << "volume euler: " << mt.volume_euler << endl;
}
INVALID_V = (uint32_t)-1;
INVALID_E = (uint32_t)-1;
std::cout << "Start Structure Simplification..." << endl;
if(SHARP_FEATURE) mf.angle_threshold = 140.0/ 180 * PAI;
triangle_mesh_feature(mf, mesh);
initial_feature(mf, fc, mesh);
extract();
ranking();
cuboid_num_original = frame.FHs.size();
sheet_num_original = All_Sheets.size();
//Slim_global_region = Slim_region * 2;
Slim_global_region = Slim_region;
return true;
}
void simplification::extract() {
std::vector<Sheet>().swap(All_Sheets);
std::vector<bool> e_flag(frame.FEs.size(), false);
while (true) {
uint32_t eid = INVALID_E;
for (uint32_t i = 0; i < frame.FEs.size(); i++) if (!e_flag[i]) { eid = i; break; }
if (eid == INVALID_E) break;
Sheet sheet; sheet.id = All_Sheets.size();
std::queue<uint32_t> e_pool; e_pool.push(eid);
while (!e_pool.empty()) {
uint32_t eid = e_pool.front(); e_pool.pop();
if (e_flag[eid]) continue; e_flag[eid] = true;
sheet.middle_es.push_back(eid);
for (uint32_t i = 0; i < frame.FEs[eid].neighbor_ffs.size(); i++) {
uint32_t fid = frame.FEs[eid].neighbor_ffs[i];
uint32_t pos = std::find(frame.FFs[fid].es.begin(), frame.FFs[fid].es.end(), eid) - frame.FFs[fid].es.begin();
uint32_t op_eid = frame.FFs[fid].es[(pos+2)%4];
if (e_flag[op_eid]) continue;
e_pool.push(op_eid);
}
}
All_Sheets.push_back(sheet);
}
for (uint32_t i = 0; i < All_Sheets.size(); i++) {
build_sheet_info(i);
}
std::vector<CHord>().swap(All_Chords);
vector<bool> f_flag(frame.FFs.size(),false);
while (true)
{
uint32_t fid = -1;
for (uint32_t i = 0; i<f_flag.size(); i++){
if (!f_flag[i]) { fid = i; break; }
}
if (fid == -1) break;
CHord cc = extract_chord(fid, f_flag);
cc.id = All_Chords.size();
cc.side = 0;
All_Chords.push_back(cc);
cc.id = All_Chords.size();
cc.side = 1;
All_Chords.push_back(cc);
}
for (uint32_t i = 0; i<All_Chords.size(); i++) {
build_chord_info(i);
}
}
bool simplification::build_sheet_info(uint32_t sheet_id){
All_Sheets[sheet_id].fake = false;
All_Sheets[sheet_id].type = Sheet_type::open;
vector<uint32_t> &cs = All_Sheets[sheet_id].cs;
vector<uint32_t> &middle_fs = All_Sheets[sheet_id].middle_fs;
vector<uint32_t> &middle_es = All_Sheets[sheet_id].middle_es;
vector<uint32_t> &middle_es_b = All_Sheets[sheet_id].middle_es_b;
for (auto eid : middle_es) {
cs.insert(cs.end(), frame.FEs[eid].neighbor_fhs.begin(), frame.FEs[eid].neighbor_fhs.end());
sort(cs.begin(), cs.end());
cs.erase(unique(cs.begin(), cs.end()), cs.end());
middle_fs.insert(middle_fs.end(), frame.FEs[eid].neighbor_ffs.begin(), frame.FEs[eid].neighbor_ffs.end());
sort(middle_fs.begin(), middle_fs.end());
middle_fs.erase(unique(middle_fs.begin(), middle_fs.end()), middle_fs.end());
if (frame.FEs[eid].boundary) middle_es_b.push_back(eid);
}
if(!middle_es_b.size()) All_Sheets[sheet_id].type = Sheet_type::close;
vector<short> V_flag(frame.FVs.size(), 0);
for (auto eid : middle_es) {
uint32_t v1 = frame.FEs[eid].vs[0];
uint32_t v2 = frame.FEs[eid].vs[1];
V_flag[v1]++;
V_flag[v2]++;
if (V_flag[v1] > 1 || V_flag[v2] > 1) {
All_Sheets[sheet_id].type = Sheet_type::tagent;
break;
}
}
sort(middle_fs.begin(), middle_fs.end());
for (auto cid:cs){
bool all_middle = true;
vector<uint32_t> fs = frame.FHs[cid].fs;
sort(fs.begin(), fs.end());
vector<uint32_t> mfs;
set_intersection(fs.begin(), fs.end(), middle_fs.begin(), middle_fs.end(), back_inserter(mfs));
if (!mfs.size()) {
All_Sheets[sheet_id].type = Sheet_type::intersect;
break;
}
}
vector<uint32_t> &fs = All_Sheets[sheet_id].fs;
vector<uint32_t> &left_fs = All_Sheets[sheet_id].left_fs;
vector<uint32_t> &right_fs = All_Sheets[sheet_id].right_fs;
for (auto cid : cs) fs.insert(fs.end(), frame.FHs[cid].fs.begin(), frame.FHs[cid].fs.end());
sort(fs.begin(), fs.end()); fs.erase(unique(fs.begin(), fs.end()), fs.end());
vector<uint32_t> &twoside_fs = All_Sheets[sheet_id].side_fs;
vector<bool> F_flag(frame.FFs.size(),true);
for (auto fid : middle_fs)F_flag[fid] = false;
for (auto fid : fs) if(F_flag[fid]) twoside_fs.push_back(fid);
fill(F_flag.begin(), F_flag.end(), false);
for (auto fid : twoside_fs)F_flag[fid] = true;
if (!twoside_fs.size()) { cout << "ERROR, no side fs" << endl; system("PAUSE"); }
queue<uint32_t> fs_pool;
fs_pool.push(twoside_fs[0]);
while (!fs_pool.empty()){
auto fid = fs_pool.front(); fs_pool.pop();
if (!F_flag[fid]) continue; F_flag[fid] = false;
left_fs.push_back(fid);
for (auto eid: frame.FFs[fid].es)
for (auto nfid : frame.FEs[eid].neighbor_ffs)
if (F_flag[nfid]) fs_pool.push(nfid);
}
for (auto fid : twoside_fs)if(F_flag[fid]) right_fs.push_back(fid);
if (All_Sheets[sheet_id].type == Sheet_type::tagent || All_Sheets[sheet_id].type == Sheet_type::intersect)
return true;
else if (left_fs.size() != right_fs.size()) { All_Sheets[sheet_id].type = Sheet_type::mobius; return true; }
vector<uint32_t> &left_es = All_Sheets[sheet_id].left_es;
vector<uint32_t> &right_es = All_Sheets[sheet_id].right_es;
for (auto fid : left_fs) left_es.insert(left_es.end(), frame.FFs[fid].es.begin(), frame.FFs[fid].es.end());
sort(left_es.begin(), left_es.end()); left_es.erase(unique(left_es.begin(), left_es.end()), left_es.end());
for (auto fid : right_fs) right_es.insert(right_es.end(), frame.FFs[fid].es.begin(), frame.FFs[fid].es.end());
sort(right_es.begin(), right_es.end()); right_es.erase(unique(right_es.begin(), right_es.end()), right_es.end());
bool left = false, right = false, bl = true, br = true;
for (auto eid:left_es){
int size = frame.FEs[eid].neighbor_fhs.size();
if ((!frame.FEs[eid].boundary && size != Interior_RegularE) || (frame.FEs[eid].boundary && size != Boundary_RegularE))
left = true;
if (!frame.FEs[eid].boundary) bl = false;
}
for (auto eid : right_es) {
int size = frame.FEs[eid].neighbor_fhs.size();
if ((!frame.FEs[eid].boundary && size != Interior_RegularE) || (frame.FEs[eid].boundary && size != Boundary_RegularE))
right = true;
if (!frame.FEs[eid].boundary) br = false;
}
if (!(left&&right) && !bl && !br) All_Sheets[sheet_id].fake = true;
return true;
}
CHord simplification::extract_chord(uint32_t &fid, vector<bool> &f_flag) {
CHord cc;
cc.type = Sheet_type::open; cc.fake = false;
uint32_t cur_f = fid;
if (!frame.FFs[cur_f].neighbor_fhs.size()) { cout << "isolated patch" << endl; system("PAUSE"); }
uint32_t cur_h = frame.FFs[cur_f].neighbor_fhs[0];
vector<uint32_t> fs, fs_right;
fs.push_back(cur_f);
while (true) {
Frame_F f_ = frame.FFs[cur_f];
Frame_H h_ = frame.FHs[cur_h];
std::vector<uint32_t> &vs = f_.vs;
std::sort(vs.begin(), vs.end());
short cors_f = -1;
for (uint32_t j = 0; j < 6; j++) {
std::vector<uint32_t> vsj = frame.FFs[h_.fs[j]].vs;
std::sort(vsj.begin(), vsj.end());
std::vector<uint32_t> common_vs;
std::set_intersection(vs.begin(), vs.end(), vsj.begin(), vsj.end(), std::back_inserter(common_vs));
if (common_vs.size())continue; else { cors_f = j; break; }
}
if(cors_f == -1) {
cout << "problematic cuboid" << endl; system("PAUSE");
}
uint32_t neighbor_f = h_.fs[cors_f];
uint32_t neighbor_h = -1;
Frame_F f = frame.FFs[neighbor_f];
for (auto fhid: f.neighbor_fhs) if (fhid != cur_h) neighbor_h = fhid;
cur_f = neighbor_f;
cur_h = neighbor_h;
if (find(fs.begin(),fs.end(), cur_f) != fs.end()){
cc.type = Sheet_type::close;
break;
}
fs.push_back(cur_f);
if (cur_h == -1) break;
}
cur_f = fid;
if (cc.type != Sheet_type::close && frame.FFs[cur_f].neighbor_fhs.size() > 1) {
cur_h = frame.FFs[cur_f].neighbor_fhs[1];
while (true) {
Frame_F f_ = frame.FFs[cur_f];
Frame_H h_ = frame.FHs[cur_h];
std::vector<uint32_t> &vs = f_.vs;
std::sort(vs.begin(), vs.end());
short cors_f = -1;
for (uint32_t j = 0; j < 6; j++) {
std::vector<uint32_t> vsj = frame.FFs[h_.fs[j]].vs;
std::sort(vsj.begin(), vsj.end());
std::vector<uint32_t> common_vs;
std::set_intersection(vs.begin(), vs.end(), vsj.begin(), vsj.end(), std::back_inserter(common_vs));
if (common_vs.size())continue; else { cors_f = j; break; }
}
if (cors_f == -1) {
cout << "problematic cuboid" << endl; system("PAUSE");
}
uint32_t neighbor_f = h_.fs[cors_f];
if (find(fs.begin(), fs.end(), neighbor_f) != fs.end()) {
cout << "problematic cuboid" << endl; system("PAUSE");
}
uint32_t neighbor_h = -1;
Frame_F f = frame.FFs[neighbor_f];
for (auto fhid : f.neighbor_fhs) if (fhid != cur_h) neighbor_h = fhid;
cur_f = neighbor_f;
cur_h = neighbor_h;
fs_right.push_back(cur_f);
if (cur_h == -1) break;
}
}
reverse(fs_right.begin(), fs_right.end());
cc.parallel_fs = fs_right;
cc.parallel_fs.insert(cc.parallel_fs.end(), fs.begin(), fs.end());
for (auto fid : cc.parallel_fs) { f_flag[fid] = true; sort(frame.FFs[fid].neighbor_fhs.begin(), frame.FFs[fid].neighbor_fhs.end()); }
vector<uint32_t> v_di = frame.FFs[cc.parallel_fs[0]].vs;
for (uint32_t i = 0; i<4; i++){ cc.parallel_ns[i].push_back(v_di[i]); }
for (uint32_t i = 1; i<cc.parallel_fs.size(); i++) {
vector<uint32_t> sharedhs;
set_intersection(frame.FFs[cc.parallel_fs[i - 1]].neighbor_fhs.begin(), frame.FFs[cc.parallel_fs[i - 1]].neighbor_fhs.end(),
frame.FFs[cc.parallel_fs[i]].neighbor_fhs.begin(), frame.FFs[cc.parallel_fs[i]].neighbor_fhs.end(),
back_inserter(sharedhs));
cc.cs.push_back(sharedhs[0]);
if (cc.type == Sheet_type::close && i == cc.parallel_fs.size() - 1){
sharedhs.clear();
set_intersection(frame.FFs[cc.parallel_fs[0]].neighbor_fhs.begin(), frame.FFs[cc.parallel_fs[0]].neighbor_fhs.end(),
frame.FFs[cc.parallel_fs[i]].neighbor_fhs.begin(), frame.FFs[cc.parallel_fs[i]].neighbor_fhs.end(),
back_inserter(sharedhs));
cc.cs.push_back(sharedhs[0]);
}
vector<uint32_t> &v_di_cur = frame.FFs[cc.parallel_fs[i]].vs;
int cid = cc.cs[i - 1];
int v0 = v_di[0], v1 = v_di[1];
for (int j = 0; j < 4; j++) {
int v2 = v_di_cur[j], v3 = v_di_cur[(j + 1)%4];
vector<uint32_t> vs0;
vs0.push_back(v0);
vs0.push_back(v1);
vs0.push_back(v2);
vs0.push_back(v3);
sort(vs0.begin(), vs0.end());
int whichf = -1;
for (auto fid : frame.FHs[cid].fs) {
vector<uint32_t> vs1 = frame.FFs[fid].vs;
sort(vs1.begin(), vs1.end());
if (std::equal(vs0.begin(), vs0.end(), vs1.begin())) {whichf = fid; break;}
}
if (whichf != -1) {
vector<uint32_t> &nvs_pre = frame.FVs[v0].neighbor_fvs;
if (find(nvs_pre.begin(), nvs_pre.end(), v2) != nvs_pre.end())
for (int k = 0; k < 4; k++) cc.parallel_ns[k].push_back(v_di_cur[(j + k) % 4]);
else for (int k = 0; k < 4; k++) cc.parallel_ns[k].push_back(v_di_cur[(j - k + 5) % 4]);
for (int k = 0; k < 4; k++) v_di[k] = cc.parallel_ns[k][cc.parallel_ns[k].size() - 1];
break;
}
}
}
return cc;
}
bool simplification::build_chord_info(uint32_t id) {
CHord &cc = All_Chords[id];
cc.fake = false;
for (uint32_t i = 0; i < 4; i++)
for (auto vid : cc.parallel_ns[i]) {
sort(frame.FVs[vid].neighbor_fes.begin(), frame.FVs[vid].neighbor_fes.end());
sort(frame.FVs[vid].neighbor_ffs.begin(), frame.FVs[vid].neighbor_ffs.end());
}
for (uint32_t i = 0; i<4; i++){
for (uint32_t j = 0; j < cc.parallel_ns[i].size(); j++) {
uint32_t v0 = cc.parallel_ns[i][j], v1 = cc.parallel_ns[(i + 1) % 4][j];
int fid;
if (cc.type == Sheet_type::close && j == cc.parallel_fs.size() - 1)
fid = cc.parallel_fs[0];
else fid = cc.parallel_fs[j];
for(uint32_t k=0;k<4;k++)
if ((v0 == frame.FFs[fid].vs[k] && v1 == frame.FFs[fid].vs[(k + 1) % 4]) || (v1 == frame.FFs[fid].vs[k] && v0 == frame.FFs[fid].vs[(k + 1) % 4])) {
cc.parallel_es[i].push_back(frame.FFs[fid].es[k]);
break;
}
if (j > 0) {
vector<uint32_t> vs;
vs.push_back(cc.parallel_ns[i][j]);
vs.push_back(cc.parallel_ns[(i + 1) % 4][j]);
vs.push_back(cc.parallel_ns[(i + 1) % 4][j - 1]);
vs.push_back(cc.parallel_ns[i][j - 1]);
int hid = cc.cs[j-1]; fid = -1;
for (uint32_t k = 0; k < 6; k++) {
fid = frame.FHs[hid].fs[k];
vector<uint32_t> &vs1 = frame.FFs[fid].vs;
bool equal = true;
for (auto vid1 : vs1) {
bool found = false;
for (auto vid0 : vs) { if (vid1 == vid0) { found = true; break; } }
if (!found) { equal = false; break; }
}
if (equal) break;
}
if (fid == -1) { cout << "error in build chord info" << endl; system("PAUSE"); }
cc.vertical_fs[i].push_back(fid);
for (uint32_t k = 0; k<4; k++)
if ((vs[0] == frame.FFs[fid].vs[k] && vs[3] == frame.FFs[fid].vs[(k + 1) % 4]) || (vs[3] == frame.FFs[fid].vs[k] && vs[0] == frame.FFs[fid].vs[(k + 1) % 4])) {
cc.vertical_es[i].push_back(frame.FFs[fid].es[k]);
break;
}
}
if (cc.type == Sheet_type::close && j == cc.parallel_ns[i].size() - 1) {
vector<uint32_t> vs;
vs.push_back(cc.parallel_ns[i][j]);
vs.push_back(cc.parallel_ns[(i + 1) % 4][j]);
vs.push_back(cc.parallel_ns[(i + 1) % 4][0]);
vs.push_back(cc.parallel_ns[i][0]);
int hid = cc.cs[j]; fid = -1;
for (uint32_t k = 0; k < 6; k++) {
fid = frame.FHs[hid].fs[k];
vector<uint32_t> &vs1 = frame.FFs[fid].vs;
bool equal = true;
for (auto vid1 : vs1) {
bool found = false;
for (auto vid0 : vs) { if (vid1 == vid0) { found = true; break; } }
if (!found) { equal = false; break; }
}
if (equal) break;
}
if (fid == -1) { cout << "error in build chord info" << endl; system("PAUSE"); }
cc.vertical_fs[i].push_back(fid);
for (uint32_t k = 0; k<4; k++)
if ((vs[0] == frame.FFs[fid].vs[k] && vs[3] == frame.FFs[fid].vs[(k + 1) % 4]) || (vs[3] == frame.FFs[fid].vs[k] && vs[0] == frame.FFs[fid].vs[(k + 1) % 4])) {
cc.vertical_es[i].push_back(frame.FFs[fid].es[k]);
break;
}
}
}
}
cc.fs = cc.parallel_fs;
for (uint32_t i = 0; i<4; i++) cc.fs.insert(cc.fs.end(),cc.vertical_fs[i].begin(), cc.vertical_fs[i].end());
for (uint32_t i = 0; i<4; i++) cc.ns.insert(cc.ns.end(), cc.parallel_ns[i].begin(), cc.parallel_ns[i].end());
for (uint32_t i = 0; i<4; i++) cc.es.insert(cc.es.end(), cc.parallel_es[i].begin(), cc.parallel_es[i].end());
for (uint32_t i = 0; i<4; i++) cc.es.insert(cc.es.end(), cc.vertical_es[i].begin(), cc.vertical_es[i].end());
vector<bool> Vs_Ind(frame.FVs.size(), false), Es_Ind(frame.FEs.size(), false), Fs_Ind(frame.FFs.size(), false), Hs_Ind(frame.FHs.size(), false);
for (auto vid : cc.ns) {
if (Vs_Ind[vid]) cc.tangent_vs.push_back(vid); Vs_Ind[vid] = true;
}
for (auto eid : cc.es) {
if (Es_Ind[eid]) cc.tangent_es.push_back(eid); Es_Ind[eid] = true;
}
for (auto cid : cc.cs) {
if (Hs_Ind[cid]) cc.tangent_cs.push_back(cid); Hs_Ind[cid] = true;
}
for (uint32_t i = 0; i<4; i++){
for (auto fid : cc.vertical_fs[i]) {
if (Fs_Ind[fid]) cc.tangent_fs.push_back(fid); Fs_Ind[fid] = true;
}
}
if (cc.tangent_vs.size() || cc.tangent_es.size() || cc.tangent_fs.size() || cc.tangent_cs.size())
cc.type = Sheet_type::tagent;
vector<uint32_t> sheet_ids;
for (int i = 0; i < 2; i++) {
uint32_t feid = cc.parallel_es[i][0];
int sheet_id = -1;
for (auto sheet : All_Sheets)
if (find(sheet.middle_es.begin(), sheet.middle_es.end(), feid) != sheet.middle_es.end()) {
sheet_id = sheet.id;
if (sheet.fake) cc.fake = true;
sheet_ids.push_back(sheet.id); break;
}
if (sheet_id == -1) { cout << "doesnot find the longer sheet" << endl; system("PAUSE"); }
}
return true;
}
void simplification::ranking() {
Candidates.clear();
char path[300];
for (uint32_t i = 0; i < All_Sheets.size(); i++) {
Tuple_Candidate tc;
get<0>(tc) = i;
get<1>(tc) = Base_Set::SHEET;
sheet_chord_weight(tc);
Candidates.push_back(tc);
}
for (uint32_t i = 0; i < All_Chords.size(); i++) {
Tuple_Candidate tc;
get<0>(tc) = i;
get<1>(tc) = Base_Set::CHORD;
sheet_chord_weight(tc);
Candidates.push_back(tc);
}
std::function<bool(Tuple_Candidate &, Tuple_Candidate &)> rank = [&](
Tuple_Candidate &s1, Tuple_Candidate &s2)->bool {
return get<2>(s1) < get<2>(s2);
};
std::sort(Candidates.begin(), Candidates.end(), rank);
}
void simplification::sheet_chord_weight(Tuple_Candidate &c){
const Float LARGE_NUM = 1.e+5;
uint32_t id = get<0>(c);
Float &weight = get<2>(c);
if (get<1>(c) == Base_Set::SHEET) {
//edge_volume ratio
float volume = 0;
Float edge_len = 0;
for (auto fe:All_Sheets[id].middle_es){
Float cur_len = 0;
for (uint32_t k = 0; k<frame.FEs[fe].es_link.size(); k++){
uint32_t eid = frame.FEs[fe].es_link[k];
uint32_t v0 = mesh.Es[eid].vs[0], v1 = mesh.Es[eid].vs[1];
cur_len += (mesh.V.col(v0) - mesh.V.col(v1)).norm();
}
edge_len += cur_len;
}
edge_len /= All_Sheets[id].middle_es.size();
All_Sheets[id].weight_len = edge_len;
All_Sheets[id].weight = All_Sheets[id].weight_len;
//valence
//Es_neighborhood
vector<vector<uint32_t>> Es_neighborhood(frame.FEs.size()), Es_group(frame.FEs.size()), Es_group_temp;
vector<bool> E_flag(frame.FEs.size(), false);
for (auto fid : All_Sheets[id].middle_fs) {
for (uint32_t i = 0; i < 2; i++) {
uint32_t eid = frame.FFs[fid].es[i];
if (find(All_Sheets[id].middle_es.begin(), All_Sheets[id].middle_es.end(), eid) == All_Sheets[id].middle_es.end()) {
uint32_t eid1 = frame.FFs[fid].es[(i + 2) % 4];
Es_neighborhood[eid].push_back(eid1);
Es_neighborhood[eid1].push_back(eid);
}
}
}
//Es_group
for (uint32_t i = 0; i < Es_neighborhood.size(); i++) {
if (!Es_neighborhood[i].size() || E_flag[i]) continue;
E_flag[i] = true;
Es_group[i].push_back(i);
vector<uint32_t> pool = Es_neighborhood[i];
while (pool.size()){
uint32_t eid = pool[pool.size() - 1]; pool.pop_back();
if (E_flag[eid]) continue;
E_flag[eid] = true;
Es_group[i].push_back(eid);
pool.insert(pool.end(), Es_neighborhood[eid].begin(), Es_neighborhood[eid].end());
}
}
for (uint32_t i = 0; i<Es_group.size(); i++){
if (!Es_group[i].size()) continue;
Es_group_temp.push_back(Es_group[i]);
}
Es_group.swap(Es_group_temp);
if (!Es_group.size()) { std::cout << "Sheet Error" << endl; system("PAUSE"); }
All_Sheets[id].weight_val_average = 0;
All_Sheets[id].weight_val_max = 0;
All_Sheets[id].weight_val_min = (numeric_limits<Float>::max)();
All_Sheets[id].valence_filter = false;
vector<bool> C_flag(frame.FHs.size(), true);
for (auto cid : All_Sheets[id].cs) C_flag[cid] = false;
for (auto es : Es_group){
vector<int> comps_result, comps_after;
for (auto eid:es) comps_after.insert(comps_after.end(), frame.FEs[eid].neighbor_fhs.begin(), frame.FEs[eid].neighbor_fhs.end());
sort(comps_after.begin(), comps_after.end()); comps_after.erase(unique(comps_after.begin(), comps_after.end()), comps_after.end());
for (auto cid : comps_after) if (C_flag[cid])comps_result.push_back(cid);
int min_val = (numeric_limits<int>::max)();
for (auto eid : es) if (min_val > frame.FEs[eid].neighbor_fhs.size()) min_val = frame.FEs[eid].neighbor_fhs.size();
if (comps_result.size() < min_val) {
All_Sheets[id].valence_filter = true;
}
}
weight = All_Sheets[id].weight;
}
else if(get<1>(c) == Base_Set::CHORD) {
CHord &cc = All_Chords[id];
Float diagonal_len = 0;
for (uint32_t i = 0; i < cc.parallel_ns[0].size();i++) {
uint32_t v0, v1; Vector3d vv0, vv1;
if (cc.side == 0) {
v0 = frame.FVs[cc.parallel_ns[1][i]].hid;
v1 = frame.FVs[cc.parallel_ns[3][i]].hid;
}
else {
v0 = frame.FVs[cc.parallel_ns[0][i]].hid;
v1 = frame.FVs[cc.parallel_ns[2][i]].hid;
}
vv0 = mesh.V.col(v0); vv1 = mesh.V.col(v1);
diagonal_len += (vv0 - vv1).norm();
}
diagonal_len *= 1.0 / cc.parallel_ns[0].size();
All_Chords[id].weight_len = diagonal_len;
All_Chords[id].weight = All_Chords[id].weight_len;
vector<vector<uint32_t>> Es_group;
//grouping
for (uint32_t i = 0; i<cc.vertical_es[0].size(); i++){
vector<uint32_t> a_group;
if (cc.side == 0){
a_group.push_back(cc.vertical_es[0][i]);
Es_group.push_back(a_group);
a_group.clear();
a_group.push_back(cc.vertical_es[1][i]);
a_group.push_back(cc.vertical_es[3][i]);
Es_group.push_back(a_group);
a_group.clear();
a_group.push_back(cc.vertical_es[2][i]);
Es_group.push_back(a_group);
}
else {
a_group.push_back(cc.vertical_es[0][i]);
Es_group.push_back(a_group);
a_group.clear();
a_group.push_back(cc.vertical_es[2][i]);
a_group.push_back(cc.vertical_es[1][i]);
Es_group.push_back(a_group);
a_group.clear();
a_group.push_back(cc.vertical_es[3][i]);
Es_group.push_back(a_group);
}
}
for (int i = 0; i<cc.parallel_es[0].size(); i++){
vector<uint32_t> a_group;
if (cc.side == 0){
a_group.push_back(cc.parallel_es[0][i]);
a_group.push_back(cc.parallel_es[3][i]);
Es_group.push_back(a_group);
a_group.clear();
a_group.push_back(cc.parallel_es[1][i]);
a_group.push_back(cc.parallel_es[2][i]);
Es_group.push_back(a_group);
}
else{
a_group.push_back(cc.parallel_es[0][i]);
a_group.push_back(cc.parallel_es[1][i]);
Es_group.push_back(a_group);
a_group.clear();
a_group.push_back(cc.parallel_es[2][i]);
a_group.push_back(cc.parallel_es[3][i]);
Es_group.push_back(a_group);
}
}
All_Chords[id].weight_val_average = 0;
All_Chords[id].weight_val_max = 0;
All_Chords[id].weight_val_min = (numeric_limits<Float>::max)();
All_Chords[id].valence_filter = false;
int interior_ = 0;
Float weight_val = 0, yita = 6; uint32_t max_valence = 0, min_valence = (numeric_limits<int32_t>::max)();
vector<Float> weight_subs;
vector<bool> C_flag(frame.FHs.size(), true);
for (auto cid : All_Chords[id].cs) C_flag[cid] = false;
for (uint32_t i = 0; i<Es_group.size(); i++){
if (!Es_group[i].size()) continue;
vector<uint32_t> comps_result, comps_after;
for (uint32_t j = 0; j<Es_group[i].size(); j++)
comps_after.insert(comps_after.end(), frame.FEs[Es_group[i][j]].neighbor_fhs.begin(), frame.FEs[Es_group[i][j]].neighbor_fhs.end());
sort(comps_after.begin(), comps_after.end()); comps_after.erase(unique(comps_after.begin(), comps_after.end()), comps_after.end());
for (auto cid : comps_after) if (C_flag[cid])comps_result.push_back(cid);
if (max_valence<comps_result.size()) max_valence = comps_result.size();
if (min_valence>comps_result.size()) min_valence = comps_result.size();
vector<uint32_t> es_boundary;
for (auto eid:Es_group[i]) if (frame.FEs[eid].boundary) es_boundary.push_back(eid);
if (es_boundary.size()) {
vector<Float> angles; Float average_angle = 0;
for (auto eid : es_boundary) {
Float angle = 0, k_ratio = 0;
dihedral_angle(angle, k_ratio, frame.FEs[eid].neighbor_fhs, eid);
angles.push_back(angle);
average_angle += angle;
}
average_angle /= es_boundary.size();
Float after = 2 * average_angle / (PAI*comps_result.size());
Float after_val = (2 * PAI) / average_angle * comps_result.size();
All_Chords[id].weight_val_average += after;
}
else{
interior_++;
int min_val = (numeric_limits<int>::max)();
for (auto eid : Es_group[i]) if (min_val > frame.FEs[eid].neighbor_fhs.size()) min_val = frame.FEs[eid].neighbor_fhs.size();
if (comps_result.size() < min_val) {
All_Chords[id].valence_filter = true;
}
Float after = 4.0 / comps_result.size();
Float after_val = comps_result.size();
All_Chords[id].weight_val_average += after;
if (All_Chords[id].weight_val_max < after_val) All_Chords[id].weight_val_max = after_val;
if (All_Chords[id].weight_val_min > after_val) All_Chords[id].weight_val_min = after_val;
}
}
All_Chords[id].weight_val_average /= Es_group.size();
weight = All_Chords[id].weight;
if (All_Chords[id].weight_val_min < 3.0 || All_Chords[id].weight_val_max > 5.0 || !(All_Chords[id].weight_val_average >= 3.0 && All_Chords[id].weight_val_average <= 5.0))
weight *= LARGE_NUM;
}else{
cout << "ERROR" << endl; system("PAUSE");
}
}
void simplification::dihedral_angle(Float &angle, Float &k_ratio, vector<uint32_t> &cs, uint32_t eid) {
vector<Float> angles;
uint32_t v1 = frame.FEs[eid].vs[0], v2 = frame.FEs[eid].vs[1];
uint32_t hv1 = frame.FVs[v1].hid;
uint32_t hv2 = frame.FVs[v2].hid;
vector<uint32_t> &nfs =frame.FEs[eid].neighbor_ffs;
for (auto cid: cs){
vector<uint32_t> &fs = frame.FHs[cid].fs, f2s;
for (auto fid : nfs) if (find(fs.begin(), fs.end(), fid) != fs.end()) f2s.push_back(fid);
uint32_t v3, v4;
for (uint32_t j = 0; j<4; j++){
if (frame.FFs[f2s[0]].vs[j] != v1&&frame.FFs[f2s[0]].vs[j] != v2) v3 = frame.FFs[f2s[0]].vs[j];
if (frame.FFs[f2s[1]].vs[j] != v1&&frame.FFs[f2s[1]].vs[j] != v2) v4 = frame.FFs[f2s[1]].vs[j];
}
uint32_t hv3 = frame.FVs[v3].hid;
uint32_t hv4 = frame.FVs[v4].hid;
Vector3d dir1, dir2, norm1, norm2;
dir1 = mesh.V.col(hv3) - mesh.V.col(hv1);
dir2 = mesh.V.col(hv3) - mesh.V.col(hv2);
norm1 = dir1.cross(dir2); norm1.normalize();
dir1 = mesh.V.col(hv4) - mesh.V.col(hv1);
dir2 = mesh.V.col(hv4) - mesh.V.col(hv2);
norm2 = dir1.cross(dir2); norm2.normalize();
angles.push_back(PAI - std::acos(norm1.dot(norm2)));
}
angle = 0;
for (uint32_t i = 0; i<angles.size(); i++) angle += angles[i];
if (angle>PAI * 2) angle = PAI * 2;
k_ratio = 2 * angle / PAI;
}
bool simplification::remove() {
std::vector<Tuple_Candidate> Candidates_temp;
Candidates_temp.insert(Candidates_temp.end(), Candidates.begin() + last_candidate_pos, Candidates.end());
Candidates_temp.insert(Candidates_temp.end(), Candidates.begin(), Candidates.begin() + last_candidate_pos);
Candidates_temp.swap(Candidates);
File_num = 0;
for (uint32_t i = 0; i < Candidates.size(); i++) {
uint32_t id = i;
File_num = id;
if (!filter_topology_feature(Candidates[id])) continue;
uint32_t feid;
if (std::get<1>(Candidates[id]) == Base_Set::SHEET) {
uint32_t sheet_id = std::get<0>(Candidates[id]);
feid = All_Sheets[sheet_id].middle_es[0];
}
else if (std::get<1>(Candidates[id]) == Base_Set::CHORD) {
uint32_t chord_id = std::get<0>(Candidates[id]);
feid = All_Chords[chord_id].parallel_es[0][0];
}
Float resolution = frame.FEs[feid].es_link.size();
Projection_range = resolution + 1;
Slim_Iteration = resolution * Slim_Iteration_base;
if (Slim_Iteration > Slim_Iteration_Limit) Slim_Iteration = Slim_Iteration_Limit;
if (Projection_range > Projection_limit)Projection_range = Projection_limit;
width_sheet = resolution;
if (!direct_collapse()) continue;
if (id >= Candidates.size() - last_candidate_pos)
last_candidate_pos = id - Candidates.size() + last_candidate_pos;
else if (id < Candidates.size() - last_candidate_pos)
last_candidate_pos = id + last_candidate_pos;
if (last_candidate_pos > All_Sheets.size()*0.3 || last_candidate_pos > 20) last_candidate_pos = 0;
return true;
}
cout << "cannot find candidate anymore" << endl;
return false;
}
bool simplification::filter_topology_feature(Tuple_Candidate &c) {
if (!TOPOLOGY && !SHARP_FEATURE) return true;
uint32_t id = get<0>(c);
if (get<1>(c) == Base_Set::SHEET) {
if (All_Sheets[id].valence_filter) {
return false;}
if (All_Sheets[id].fake) {
return false;}
vector<vector<uint32_t>> candiate_es_links, v_group;
if (!vs_pair_sheet(id, candiate_es_links, v_group)) { cout << "ERROR: no vs pairs" << endl; system("PAUSE");}
if (!target_surface_sheet(id, candiate_es_links, v_group)) {
return false;
}
if (TOPOLOGY) {
vector<bool> F_flag(frame.FFs.size(), false);
for (auto fid : All_Sheets[id].middle_fs) F_flag[fid] = true;
for (auto cid : All_Sheets[id].cs) {
vector<uint32_t> side_fs;
for (auto fid : frame.FHs[cid].fs) if (!F_flag[fid]) side_fs.push_back(fid);
if (side_fs.size() == 2 && frame.FFs[side_fs[0]].boundary && frame.FFs[side_fs[1]].boundary) {
return false;
}
}
}
}
else if (get<1>(c) == Base_Set::CHORD) {
if (All_Chords[id].type != Sheet_type::close && All_Chords[id].type != Sheet_type::open) return false;
if (All_Chords[id].valence_filter || All_Chords[id].weight_val_min < 3.0 || All_Chords[id].weight_val_max > 5.0) return false;
if (All_Chords[id].fake ) {
return false;
}
if (!vs_group_chord(id)) return false;
if (!target_surface_chord(id)) return false;
}
if (!topology_check()) {
return false;
}
return true;
}
bool simplification::vs_pair_sheet(uint32_t sheet_id, vector<vector<uint32_t>> &candiate_es_links, vector<vector<uint32_t>> &v_group) {
if (sheet_id >= All_Sheets.size()) return false;
vector<vector<uint32_t>>es_links(All_Sheets[sheet_id].middle_es.size()), es_links_temp;
for (uint32_t i = 0; i < All_Sheets[sheet_id].middle_es.size(); i++)
es_links[i] = frame.FEs[All_Sheets[sheet_id].middle_es[i]].es_link;
vector<bool> e_flag(mesh.Es.size(), false);
vector<uint32_t> v_pair(2);
while (true) {
for (uint32_t i = 0; i<es_links.size(); i++) {
if (e_flag[es_links[i][0]]) continue;
candiate_es_links.push_back(es_links[i]);
int v1, v2;
if (es_links[i].size() == 1) {
v1 = mesh.Es[es_links[i][0]].vs[0];
v2 = mesh.Es[es_links[i][0]].vs[1];
}
else {
v1 = mesh.Es[es_links[i][0]].vs[0];
for (uint32_t j = 0; j<mesh.Vs[v1].neighbor_es.size(); j++)
if (mesh.Vs[v1].neighbor_es[j] == es_links[i][1]) {
v1 = mesh.Es[es_links[i][0]].vs[1]; break;
}
uint32_t nume = es_links[i].size() - 1;
v2 = mesh.Es[es_links[i][nume]].vs[0];
for (uint32_t j = 0; j<mesh.Vs[v2].neighbor_es.size(); j++)
if (mesh.Vs[v2].neighbor_es[j] == es_links[i][nume - 1]) {
v2 = mesh.Es[es_links[i][nume]].vs[1]; break;
}
}
v_pair[0] = v1;
v_pair[1] = v2;
v_group.push_back(v_pair);
for (uint32_t j = 0; j<es_links[i].size(); j++) e_flag[es_links[i][j]] = true;
for (uint32_t j = 0; j<mesh.Es[es_links[i][0]].neighbor_fs.size(); j++) {
uint32_t nf = mesh.Es[es_links[i][0]].neighbor_fs[j];
uint32_t op_eid = INVALID_E;
for (uint32_t k = 0; k<4; k++) {
if (mesh.Fs[nf].es[k] == es_links[i][0]) {
op_eid = mesh.Fs[nf].es[(k + 2) % 4]; break;
}
}
if (op_eid == INVALID_E) {
cout << "error " << endl; system("PAUSE");
}
if (e_flag[op_eid]) continue;
uint32_t pre_nf = nf;
vector<uint32_t> es_link;
es_link.push_back(op_eid);
for (uint32_t k = 1; k<es_links[i].size(); k++) {
for (uint32_t m = 0; m<mesh.Es[es_links[i][k]].neighbor_fs.size(); m++) {
uint32_t n_f = mesh.Es[es_links[i][k]].neighbor_fs[m];
bool havesharede = false;
for (uint32_t p = 0; p<4; p++) {
for (uint32_t q = 0; q<4; q++) {
if (mesh.Fs[n_f].es[p] == mesh.Fs[pre_nf].es[q]) {
havesharede = true; break;
}
}
if (havesharede) break;
}
if (havesharede) {
pre_nf = n_f;
op_eid = INVALID_E;
for (uint32_t p = 0; p<4; p++) {
if (mesh.Fs[n_f].es[p] == es_links[i][k])
{
op_eid = mesh.Fs[n_f].es[(p + 2) % 4]; break;
}
}
if (op_eid == INVALID_E) {
cout << "error " << endl; system("PAUSE");
}
es_link.push_back(op_eid);
break;
}
}
}
es_links_temp.push_back(es_link);
}
}
if (!es_links_temp.size()) break;
else {
es_links.clear();
es_links.swap(es_links_temp);
}
}
return true;
}
bool simplification::target_surface_sheet(uint32_t sheet_id, vector<vector<uint32_t>> &candiate_es_links, vector<vector<uint32_t>> &v_group) {
vector<vector<uint32_t>> vs_links_temp(candiate_es_links.size());
for (uint32_t i = 0; i < candiate_es_links.size();i++) {
vector<uint32_t> vs_link;
uint32_t first_v = v_group[i][0]; vs_link.push_back(first_v);
for (auto eid: candiate_es_links[i]){
if (mesh.Es[eid].vs[0] == first_v) {
first_v = mesh.Es[eid].vs[1];
vs_link.push_back(first_v);
}
else if (mesh.Es[eid].vs[1] == first_v) {
first_v = mesh.Es[eid].vs[0];
vs_link.push_back(first_v);
}
}
vs_links_temp[i] = vs_link;
}
vector<bool> V_flag(mesh.Vs.size(), true);
for (auto v_link : vs_links_temp)for (uint32_t j = 1; j < v_link.size() - 1; j++) V_flag[v_link[j]] = false;
vector<vector<uint32_t>> &vs_pairs = All_Sheets[sheet_id].vs_pairs,
&vs_links = All_Sheets[sheet_id].vs_links;
vs_pairs.clear(); vs_links.clear();
for (uint32_t i = 0; i < v_group.size();i++) {
vector<uint32_t> &a_pair = v_group[i];
if (!V_flag[a_pair[0]] && !V_flag[a_pair[1]]) continue;
vs_pairs.push_back(a_pair);
vs_links.push_back(vs_links_temp[i]);
}
//grouping
vector<vector<uint32_t>> &Vs_Group = All_Sheets[sheet_id].Vs_Group;
Vs_Group.clear();
vector<bool> v_flag(mesh.Vs.size(), false);
vector<vector<uint32_t>> v_nvs(mesh.Vs.size());
for (auto a_pair: vs_pairs) {
v_nvs[a_pair[0]].push_back(a_pair[1]);