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#pragma once
//#######################################################################################
//# #
//# CLOUDCOMPARE PLUGIN: qCSF #
//# #
//# 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; version 2 or later of the License. #
//# #
//# 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. #
//# #
//# Please cite the following paper, If you use this plugin in your work. #
//# #
//# Zhang W, Qi J, Wan P, Wang H, Xie D, Wang X, Yan G. An Easy-to-Use Airborne LiDAR #
//# Data Filtering Method Based on Cloth Simulation. Remote Sensing. 2016; 8(6):501. #
//# #
//# Copyright #
//# RAMM laboratory, School of Geography, Beijing Normal University #
//# (http://ramm.bnu.edu.cn/) #
//# #
//# Wuming Zhang; Jianbo Qi; Peng Wan; Hongtao Wang #
//# #
//# contact us: 2009zwm@gmail.com; wpqjbzwm@126.com #
//# #
//#######################################################################################
//This source code is about a ground filtering algorithm for airborn LiDAR data
//based on physical process simulations, specifically cloth simulation.
//
//This code is based on a Cloth Simulation Tutorial at the cg.alexandra.dk blog.
//Thanks to Jesper Mosegaard (clothTutorial@jespermosegaard.dk)
//
//When applying the cloth simulation to LIDAR point filtering. A lot of features
//have been added to the original source code, including
//* configuration file management
//* point cloud data read/write
//* point-to-point collsion detection
//* nearest point search structure from CGAL
//* addding a terrain class
//using discrete steps (drop and pull) to approximate the physical process
//Finding the max height value in nearest N points aroud every particles, as the lowest position where the particles can get.ÿϵΧڽN㣬Ըֵ߳Ϊܵ͵㡣
//local
#include "Vec3.h"
#include "Particle.h"
//system
#include <vector>
class ccMesh;
class Cloth
{
private:
// total number of particles is num_particles_width*num_particles_height
int constraint_iterations;
//double time_step;
std::vector<Particle> particles; // all particles that are part of this cloth
// std::vector<Constraint> constraints; // alle constraints between particles as part of this cloth
//parameters of slope postpocessing
double smoothThreshold;
double heightThreshold;
//heightvalues
std::vector<double> heightvals;
//movable particle index
std::vector<int> movableIndex;
std::vector< std::vector<int> > particle_edges;
//record
inline void addConstraint(Particle *p1, Particle *p2)
{ /*constraints.push_back(Constraint(p1, p2));*/
p1->neighborsList.push_back(p2); //record the neighbor for each particle
p2->neighborsList.push_back(p1);
}
public:
inline Particle& getParticle(int x, int y) { return particles[y*num_particles_width + x]; }
inline const Particle& getParticle(int x, int y) const { return particles[y*num_particles_width + x]; }
inline Particle& getParticleByIndex(int index) { return particles[index]; }
inline const Particle& getParticleByIndex(int index) const { return particles[index]; }
int num_particles_width; // number of particles in "width" direction
int num_particles_height; // number of particles in "height" direction
Vec3 origin_pos;
double step_x, step_y;
inline int getSize() const { return num_particles_width * num_particles_height; }
inline std::vector<double>& getHeightvals() { return heightvals; }
public:
/* This is a important constructor for the entire system of particles and constraints */
Cloth( const Vec3& origin_pos,
int num_particles_width,
int num_particles_height,
double step_x,
double step_y,
double smoothThreshold,
double heightThreshold,
int rigidness/*,
double time_step*/);
void setheightvals(const std::vector<double>& heightvals)
{
this->heightvals = heightvals;
}
/** This is an important method where the time is progressed one time step for the entire cloth.
This includes calling satisfyConstraint() for every constraint, and calling timeStep() for all particles
**/
double timeStep();
/* used to add gravity to all particles */
void addForce(double f);
//detecting collision of cloth and terrain
void terrainCollision();
//implementing postpocessing to movable particles
void movableFilter();
struct XY
{
XY(int x1, int y1)
: x(x1)
, y(y1)
{}
int x;
int y;
};
void findUnmovablePoint(const std::vector<XY>& connected,
const std::vector<double>& heightvals,
std::vector<int>& edgePoints);
void handle_slop_connected( const std::vector<int>& edgePoints,
const std::vector<XY>& connected,
const std::vector< std::vector<int> >& neighbors,
const std::vector<double> &heightvals);
//! Converts the cloth to a CC mesh structure
ccMesh* toMesh() const;
};
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