Files
create/src/Mod/Mesh/App/Core/Smoothing.cpp
2022-11-22 03:10:47 +01:00

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/***************************************************************************
* Copyright (c) 2009 Werner Mayer <wmayer[at]users.sourceforge.net> *
* *
* This file is part of the FreeCAD CAx development system. *
* *
* This library is free software; you can redistribute it and/or *
* modify it under the terms of the GNU Library General Public *
* License as published by the Free Software Foundation; either *
* version 2 of the License, or (at your option) any later version. *
* *
* This library 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 Library General Public License for more details. *
* *
* You should have received a copy of the GNU Library General Public *
* License along with this library; see the file COPYING.LIB. If not, *
* write to the Free Software Foundation, Inc., 59 Temple Place, *
* Suite 330, Boston, MA 02111-1307, USA *
* *
***************************************************************************/
#include "PreCompiled.h"
#include <Base/Tools.h>
#include "Smoothing.h"
#include "Algorithm.h"
#include "Approximation.h"
#include "Iterator.h"
#include "MeshKernel.h"
using namespace MeshCore;
AbstractSmoothing::AbstractSmoothing(MeshKernel& m)
: kernel(m)
, component(Normal)
, continuity(C0)
{
}
AbstractSmoothing::~AbstractSmoothing()
{
}
void AbstractSmoothing::initialize(Component comp, Continuity cont)
{
this->component = comp;
this->continuity = cont;
}
PlaneFitSmoothing::PlaneFitSmoothing(MeshKernel& m)
: AbstractSmoothing(m)
, maximum(FLT_MAX)
{
}
PlaneFitSmoothing::~PlaneFitSmoothing()
{
}
void PlaneFitSmoothing::Smooth(unsigned int iterations)
{
MeshCore::MeshPoint center;
MeshCore::MeshPointArray PointArray = kernel.GetPoints();
MeshCore::MeshPointIterator v_it(kernel);
MeshCore::MeshRefPointToPoints vv_it(kernel);
MeshCore::MeshPointArray::_TConstIterator v_beg = kernel.GetPoints().begin();
for (unsigned int i=0; i<iterations; i++) {
Base::Vector3f N, L;
for (v_it.Begin(); v_it.More(); v_it.Next()) {
MeshCore::PlaneFit pf;
pf.AddPoint(*v_it);
center = *v_it;
const std::set<PointIndex>& cv = vv_it[v_it.Position()];
if (cv.size() < 3)
continue;
std::set<PointIndex>::const_iterator cv_it;
for (cv_it = cv.begin(); cv_it !=cv.end(); ++cv_it) {
pf.AddPoint(v_beg[*cv_it]);
center += v_beg[*cv_it];
}
float scale = 1.0f/(static_cast<float>(cv.size())+1.0f);
center.Scale(scale,scale,scale);
// get the mean plane of the current vertex with the surrounding vertices
pf.Fit();
N = pf.GetNormal();
N.Normalize();
// look in which direction we should move the vertex
L.Set(v_it->x - center.x, v_it->y - center.y, v_it->z - center.z);
if (N*L < 0.0f)
N.Scale(-1.0, -1.0, -1.0);
// maximum value to move is distance to mean plane
float d = std::min<float>(fabs(this->maximum),fabs(N*L));
N.Scale(d,d,d);
PointArray[v_it.Position()].Set(v_it->x - N.x, v_it->y - N.y, v_it->z - N.z);
}
// assign values without affecting iterators
PointIndex count = kernel.CountPoints();
for (PointIndex idx = 0; idx < count; idx++) {
kernel.SetPoint(idx, PointArray[idx]);
}
}
}
void PlaneFitSmoothing::SmoothPoints(unsigned int iterations, const std::vector<PointIndex>& point_indices)
{
MeshCore::MeshPoint center;
MeshCore::MeshPointArray PointArray = kernel.GetPoints();
MeshCore::MeshPointIterator v_it(kernel);
MeshCore::MeshRefPointToPoints vv_it(kernel);
MeshCore::MeshPointArray::_TConstIterator v_beg = kernel.GetPoints().begin();
for (unsigned int i=0; i<iterations; i++) {
Base::Vector3f N, L;
for (std::vector<PointIndex>::const_iterator it = point_indices.begin(); it != point_indices.end(); ++it) {
v_it.Set(*it);
MeshCore::PlaneFit pf;
pf.AddPoint(*v_it);
center = *v_it;
const std::set<PointIndex>& cv = vv_it[v_it.Position()];
if (cv.size() < 3)
continue;
std::set<PointIndex>::const_iterator cv_it;
for (cv_it = cv.begin(); cv_it !=cv.end(); ++cv_it) {
pf.AddPoint(v_beg[*cv_it]);
center += v_beg[*cv_it];
}
float scale = 1.0f/(static_cast<float>(cv.size())+1.0f);
center.Scale(scale,scale,scale);
// get the mean plane of the current vertex with the surrounding vertices
pf.Fit();
N = pf.GetNormal();
N.Normalize();
// look in which direction we should move the vertex
L.Set(v_it->x - center.x, v_it->y - center.y, v_it->z - center.z);
if (N*L < 0.0f)
N.Scale(-1.0, -1.0, -1.0);
// maximum value to move is distance to mean plane
float d = std::min<float>(fabs(this->maximum),fabs(N*L));
N.Scale(d,d,d);
PointArray[v_it.Position()].Set(v_it->x - N.x, v_it->y - N.y, v_it->z - N.z);
}
// assign values without affecting iterators
PointIndex count = kernel.CountPoints();
for (PointIndex idx = 0; idx < count; idx++) {
kernel.SetPoint(idx, PointArray[idx]);
}
}
}
LaplaceSmoothing::LaplaceSmoothing(MeshKernel& m)
: AbstractSmoothing(m), lambda(0.6307)
{
}
LaplaceSmoothing::~LaplaceSmoothing()
{
}
void LaplaceSmoothing::Umbrella(const MeshRefPointToPoints& vv_it,
const MeshRefPointToFacets& vf_it, double stepsize)
{
const MeshCore::MeshPointArray& points = kernel.GetPoints();
MeshCore::MeshPointArray::_TConstIterator v_it,
v_beg = points.begin(), v_end = points.end();
PointIndex pos = 0;
for (v_it = points.begin(); v_it != v_end; ++v_it,++pos) {
const std::set<PointIndex>& cv = vv_it[pos];
if (cv.size() < 3)
continue;
if (cv.size() != vf_it[pos].size()) {
// do nothing for border points
continue;
}
size_t n_count = cv.size();
double w;
w=1.0/double(n_count);
double delx=0.0,dely=0.0,delz=0.0;
std::set<PointIndex>::const_iterator cv_it;
for (cv_it = cv.begin(); cv_it !=cv.end(); ++cv_it) {
delx += w*static_cast<double>((v_beg[*cv_it]).x-v_it->x);
dely += w*static_cast<double>((v_beg[*cv_it]).y-v_it->y);
delz += w*static_cast<double>((v_beg[*cv_it]).z-v_it->z);
}
float x = static_cast<float>(static_cast<double>(v_it->x)+stepsize*delx);
float y = static_cast<float>(static_cast<double>(v_it->y)+stepsize*dely);
float z = static_cast<float>(static_cast<double>(v_it->z)+stepsize*delz);
kernel.SetPoint(pos,x,y,z);
}
}
void LaplaceSmoothing::Umbrella(const MeshRefPointToPoints& vv_it,
const MeshRefPointToFacets& vf_it, double stepsize,
const std::vector<PointIndex>& point_indices)
{
const MeshCore::MeshPointArray& points = kernel.GetPoints();
MeshCore::MeshPointArray::_TConstIterator v_beg = points.begin();
for (std::vector<PointIndex>::const_iterator pos = point_indices.begin(); pos != point_indices.end(); ++pos) {
const std::set<PointIndex>& cv = vv_it[*pos];
if (cv.size() < 3)
continue;
if (cv.size() != vf_it[*pos].size()) {
// do nothing for border points
continue;
}
size_t n_count = cv.size();
double w;
w=1.0/double(n_count);
double delx=0.0,dely=0.0,delz=0.0;
std::set<PointIndex>::const_iterator cv_it;
for (cv_it = cv.begin(); cv_it !=cv.end(); ++cv_it) {
delx += w*static_cast<double>((v_beg[*cv_it]).x-(v_beg[*pos]).x);
dely += w*static_cast<double>((v_beg[*cv_it]).y-(v_beg[*pos]).y);
delz += w*static_cast<double>((v_beg[*cv_it]).z-(v_beg[*pos]).z);
}
float x = static_cast<float>(static_cast<double>((v_beg[*pos]).x)+stepsize*delx);
float y = static_cast<float>(static_cast<double>((v_beg[*pos]).y)+stepsize*dely);
float z = static_cast<float>(static_cast<double>((v_beg[*pos]).z)+stepsize*delz);
kernel.SetPoint(*pos,x,y,z);
}
}
void LaplaceSmoothing::Smooth(unsigned int iterations)
{
MeshCore::MeshRefPointToPoints vv_it(kernel);
MeshCore::MeshRefPointToFacets vf_it(kernel);
for (unsigned int i=0; i<iterations; i++) {
Umbrella(vv_it, vf_it, lambda);
}
}
void LaplaceSmoothing::SmoothPoints(unsigned int iterations, const std::vector<PointIndex>& point_indices)
{
MeshCore::MeshRefPointToPoints vv_it(kernel);
MeshCore::MeshRefPointToFacets vf_it(kernel);
for (unsigned int i=0; i<iterations; i++) {
Umbrella(vv_it, vf_it, lambda, point_indices);
}
}
TaubinSmoothing::TaubinSmoothing(MeshKernel& m)
: LaplaceSmoothing(m), micro(0.0424)
{
}
TaubinSmoothing::~TaubinSmoothing()
{
}
void TaubinSmoothing::Smooth(unsigned int iterations)
{
MeshCore::MeshRefPointToPoints vv_it(kernel);
MeshCore::MeshRefPointToFacets vf_it(kernel);
// Theoretically Taubin does not shrink the surface
iterations = (iterations+1)/2; // two steps per iteration
for (unsigned int i=0; i<iterations; i++) {
Umbrella(vv_it, vf_it, lambda);
Umbrella(vv_it, vf_it, -(lambda+micro));
}
}
void TaubinSmoothing::SmoothPoints(unsigned int iterations, const std::vector<PointIndex>& point_indices)
{
MeshCore::MeshRefPointToPoints vv_it(kernel);
MeshCore::MeshRefPointToFacets vf_it(kernel);
// Theoretically Taubin does not shrink the surface
iterations = (iterations+1)/2; // two steps per iteration
for (unsigned int i=0; i<iterations; i++) {
Umbrella(vv_it, vf_it, lambda, point_indices);
Umbrella(vv_it, vf_it, -(lambda+micro), point_indices);
}
}
namespace {
using AngleNormal = std::pair<double, Base::Vector3d>;
inline Base::Vector3d find_median(std::vector<AngleNormal> &container)
{
auto compare_angle_normal = [](const AngleNormal& an1, const AngleNormal& an2) {
return an1.first < an2.first;
};
size_t n = container.size() / 2;
std::nth_element(container.begin(), container.begin() + n, container.end(), compare_angle_normal);
if ((container.size() % 2) == 1) {
return container[n].second;
}
else {
// even sized vector -> average the two middle values
auto max_it = std::max_element(container.begin(), container.begin() + n, compare_angle_normal);
Base::Vector3d vec = (max_it->second + container[n].second) / 2.0;
vec.Normalize();
return vec;
}
}
}
MedianFilterSmoothing::MedianFilterSmoothing(MeshKernel& m)
: AbstractSmoothing(m), weights(1)
{
}
MedianFilterSmoothing::~MedianFilterSmoothing()
{
}
void MedianFilterSmoothing::Smooth(unsigned int iterations)
{
std::vector<unsigned long> point_indices(kernel.CountPoints());
std::generate(point_indices.begin(), point_indices.end(), Base::iotaGen<unsigned long>(0));
MeshCore::MeshRefFacetToFacets ff_it(kernel);
MeshCore::MeshRefPointToFacets vf_it(kernel);
for (unsigned int i=0; i<iterations; i++) {
UpdatePoints(ff_it, vf_it, point_indices);
}
}
void MedianFilterSmoothing::SmoothPoints(unsigned int iterations, const std::vector<PointIndex>& point_indices)
{
MeshCore::MeshRefFacetToFacets ff_it(kernel);
MeshCore::MeshRefPointToFacets vf_it(kernel);
for (unsigned int i=0; i<iterations; i++) {
UpdatePoints(ff_it, vf_it, point_indices);
}
}
void MedianFilterSmoothing::UpdatePoints(const MeshRefFacetToFacets& ff_it,
const MeshRefPointToFacets& vf_it,
const std::vector<PointIndex>& point_indices)
{
const MeshCore::MeshPointArray& points = kernel.GetPoints();
const MeshCore::MeshFacetArray& facets = kernel.GetFacets();
// Initialize the array with the real normals
std::vector<Base::Vector3d> faceNormals;
faceNormals.reserve(facets.size());
MeshCore::MeshFacetIterator iter(kernel);
for (iter.Init(); iter.More(); iter.Next()) {
faceNormals.emplace_back(Base::toVector<double>(iter->GetNormal()));
}
// Step 1: determine face normals
for (FacetIndex pos = 0; pos < facets.size(); pos++) {
iter.Set(pos);
Base::Vector3d refNormal = Base::toVector<double>(iter->GetNormal());
const std::set<FacetIndex>& cv = ff_it[pos];
const MeshCore::MeshFacet& facet = facets[pos];
std::vector<AngleNormal> anglesWithFaces;
for (auto fi : cv) {
iter.Set(fi);
Base::Vector3d faceNormal = Base::toVector<double>(iter->GetNormal());
double angle = refNormal.GetAngle(faceNormal);
int absWeight = std::abs(weights);
if (absWeight > 1 && facet.IsNeighbour(fi)) {
if (weights < 0) {
angle = -angle;
}
for (int i = 0; i < absWeight; i++) {
anglesWithFaces.emplace_back(angle, faceNormal);
}
}
else {
anglesWithFaces.emplace_back(angle, faceNormal);
}
}
faceNormals[pos] = find_median(anglesWithFaces);
}
// Step 2: move vertices
for (auto pos : point_indices) {
Base::Vector3d P = Base::toVector<double>(points[pos]);
const std::set<FacetIndex>& cv = vf_it[pos];
double totalArea = 0.0;
Base::Vector3d totalvT;
for (auto it : cv) {
iter.Set(it);
double faceArea = iter->Area();
totalArea += faceArea;
Base::Vector3d C = Base::toVector<double>(iter->GetGravityPoint());
Base::Vector3d PC = C - P;
Base::Vector3d mT = faceNormals[it];
Base::Vector3d vT = (PC * mT) * mT;
totalvT += vT * faceArea;
}
P = P + totalvT / totalArea;
kernel.SetPoint(pos, Base::toVector<float>(P));
}
}