// This file is part of libigl, a simple c++ geometry processing library.
//
// Copyright (C) 2015 Alec Jacobson <alecjacobson@gmail.com>
//
// 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/.
#ifndef IGL_COLLAPSE_EDGE_H
#define IGL_COLLAPSE_EDGE_H
#include "igl_inline.h"
#include <Eigen/Core>
#include <vector>
#include <set>
namespace igl
{
// Assumes (V,F) is a closed manifold mesh (except for previously collapsed
// faces which should be set to:
// [IGL_COLLAPSE_EDGE_NULL IGL_COLLAPSE_EDGE_NULL IGL_COLLAPSE_EDGE_NULL].
// Collapses exactly two faces and exactly 3 edges from E (e and one side of
// each face gets collapsed to the other). This is implemented in a way that
// it can be repeatedly called until satisfaction and then the garbage in F
// can be collected by removing NULL faces.
//
// Inputs:
// e index into E of edge to try to collapse. E(e,:) = [s d] or [d s] so
// that s<d, then d is collapsed to s.
/// p dim list of vertex position where to place merged vertex
// Inputs/Outputs:
// V #V by dim list of vertex positions, lesser index of E(e,:) will be set
// to midpoint of edge.
// F #F by 3 list of face indices into V.
// E #E by 2 list of edge indices into V.
// EMAP #F*3 list of indices into E, mapping each directed edge to unique
// unique edge in E
// EF #E by 2 list of edge flaps, EF(e,0)=f means e=(i-->j) is the edge of
// F(f,:) opposite the vth corner, where EI(e,0)=v. Similarly EF(e,1) "
// e=(j->i)
// EI #E by 2 list of edge flap corners (see above).
// e1 index into E of edge collpased on left
// e2 index into E of edge collpased on left
// f1 index into E of edge collpased on left
// f2 index into E of edge collpased on left
// Returns true if edge was collapsed
#define IGL_COLLAPSE_EDGE_NULL 0
IGL_INLINE bool collapse_edge(
const int e,
const Eigen::RowVectorXd & p,
Eigen::MatrixXd & V,
Eigen::MatrixXi & F,
Eigen::MatrixXi & E,
Eigen::VectorXi & EMAP,
Eigen::MatrixXi & EF,
Eigen::MatrixXi & EI,
int & e1,
int & e2,
int & f1,
int & f2);
IGL_INLINE bool collapse_edge(
const int e,
const Eigen::RowVectorXd & p,
Eigen::MatrixXd & V,
Eigen::MatrixXi & F,
Eigen::MatrixXi & E,
Eigen::VectorXi & EMAP,
Eigen::MatrixXi & EF,
Eigen::MatrixXi & EI);
// Collapse least-cost edge from a priority queue and update queue
//
// Inputs/Outputs:
// cost_and_placement function computing cost of collapsing an edge and 3d
// position where it should be placed:
// cost_and_placement(V,F,E,EMAP,EF,EI,cost,placement);
// **If the edges is collapsed** then this function will be called on all
// edges of all faces previously incident on the endpoints of the
// collapsed edge.
// Q queue containing pairs of costs and edge indices
// Qit list of iterators so that Qit[e] --> iterator of edge e in Q
// C #E by dim list of stored placements
IGL_INLINE bool collapse_edge(
const std::function<void(
const int,
const Eigen::MatrixXd &,
const Eigen::MatrixXi &,
const Eigen::MatrixXi &,
const Eigen::VectorXi &,
const Eigen::MatrixXi &,
const Eigen::MatrixXi &,
double &,
Eigen::RowVectorXd &)> & cost_and_placement,
Eigen::MatrixXd & V,
Eigen::MatrixXi & F,
Eigen::MatrixXi & E,
Eigen::VectorXi & EMAP,
Eigen::MatrixXi & EF,
Eigen::MatrixXi & EI,
std::set<std::pair<double,int> > & Q,
std::vector<std::set<std::pair<double,int> >::iterator > & Qit,
Eigen::MatrixXd & C);
// Inputs:
// pre_collapse callback called with index of edge whose collapse is about
// to be attempted. This function should return whether to **proceed**
// with the collapse: returning true means "yes, try to collapse",
// returning false means "No, consider this edge 'uncollapsable', behave
// as if collapse_edge(e) returned false.
// post_collapse callback called with index of edge whose collapse was
// just attempted and a flag revealing whether this was successful.
IGL_INLINE bool collapse_edge(
const std::function<void(
const int,
const Eigen::MatrixXd &,
const Eigen::MatrixXi &,
const Eigen::MatrixXi &,
const Eigen::VectorXi &,
const Eigen::MatrixXi &,
const Eigen::MatrixXi &,
double &,
Eigen::RowVectorXd &)> & cost_and_placement,
const std::function<bool(
const Eigen::MatrixXd & ,/*V*/
const Eigen::MatrixXi & ,/*F*/
const Eigen::MatrixXi & ,/*E*/
const Eigen::VectorXi & ,/*EMAP*/
const Eigen::MatrixXi & ,/*EF*/
const Eigen::MatrixXi & ,/*EI*/
const std::set<std::pair<double,int> > & ,/*Q*/
const std::vector<std::set<std::pair<double,int> >::iterator > &,/*Qit*/
const Eigen::MatrixXd & ,/*C*/
const int /*e*/
)> & pre_collapse,
const std::function<void(
const Eigen::MatrixXd & , /*V*/
const Eigen::MatrixXi & , /*F*/
const Eigen::MatrixXi & , /*E*/
const Eigen::VectorXi & ,/*EMAP*/
const Eigen::MatrixXi & , /*EF*/
const Eigen::MatrixXi & , /*EI*/
const std::set<std::pair<double,int> > & , /*Q*/
const std::vector<std::set<std::pair<double,int> >::iterator > &, /*Qit*/
const Eigen::MatrixXd & , /*C*/
const int , /*e*/
const int , /*e1*/
const int , /*e2*/
const int , /*f1*/
const int , /*f2*/
const bool /*collapsed*/
)> & post_collapse,
Eigen::MatrixXd & V,
Eigen::MatrixXi & F,
Eigen::MatrixXi & E,
Eigen::VectorXi & EMAP,
Eigen::MatrixXi & EF,
Eigen::MatrixXi & EI,
std::set<std::pair<double,int> > & Q,
std::vector<std::set<std::pair<double,int> >::iterator > & Qit,
Eigen::MatrixXd & C);
IGL_INLINE bool collapse_edge(
const std::function<void(
const int,
const Eigen::MatrixXd &,
const Eigen::MatrixXi &,
const Eigen::MatrixXi &,
const Eigen::VectorXi &,
const Eigen::MatrixXi &,
const Eigen::MatrixXi &,
double &,
Eigen::RowVectorXd &)> & cost_and_placement,
const std::function<bool(
const Eigen::MatrixXd & ,/*V*/
const Eigen::MatrixXi & ,/*F*/
const Eigen::MatrixXi & ,/*E*/
const Eigen::VectorXi & ,/*EMAP*/
const Eigen::MatrixXi & ,/*EF*/
const Eigen::MatrixXi & ,/*EI*/
const std::set<std::pair<double,int> > & ,/*Q*/
const std::vector<std::set<std::pair<double,int> >::iterator > &,/*Qit*/
const Eigen::MatrixXd & ,/*C*/
const int /*e*/
)> & pre_collapse,
const std::function<void(
const Eigen::MatrixXd & , /*V*/
const Eigen::MatrixXi & , /*F*/
const Eigen::MatrixXi & , /*E*/
const Eigen::VectorXi & ,/*EMAP*/
const Eigen::MatrixXi & , /*EF*/
const Eigen::MatrixXi & , /*EI*/
const std::set<std::pair<double,int> > & , /*Q*/
const std::vector<std::set<std::pair<double,int> >::iterator > &, /*Qit*/
const Eigen::MatrixXd & , /*C*/
const int , /*e*/
const int , /*e1*/
const int , /*e2*/
const int , /*f1*/
const int , /*f2*/
const bool /*collapsed*/
)> & post_collapse,
Eigen::MatrixXd & V,
Eigen::MatrixXi & F,
Eigen::MatrixXi & E,
Eigen::VectorXi & EMAP,
Eigen::MatrixXi & EF,
Eigen::MatrixXi & EI,
std::set<std::pair<double,int> > & Q,
std::vector<std::set<std::pair<double,int> >::iterator > & Qit,
Eigen::MatrixXd & C,
int & e,
int & e1,
int & e2,
int & f1,
int & f2);
}
#ifndef IGL_STATIC_LIBRARY
# include "collapse_edge.cpp"
#endif
#endif