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diff --git a/src/3rdparty/adaptagrams/libvpsc/solve_VPSC.cpp b/src/3rdparty/adaptagrams/libvpsc/solve_VPSC.cpp
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+/*
+ * vim: ts=4 sw=4 et tw=0 wm=0
+ *
+ * libvpsc - A solver for the problem of Variable Placement with
+ * Separation Constraints.
+ *
+ * Copyright (C) 2005-2008 Monash University
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ * See the file LICENSE.LGPL distributed with the library.
+ *
+ * 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.
+ *
+ * Author(s): Tim Dwyer
+ * Michael Wybrow
+*/
+
+#include <cmath>
+#include <sstream>
+#include <map>
+#include <cfloat>
+#include <set>
+
+#include "libvpsc/constraint.h"
+#include "libvpsc/block.h"
+#include "libvpsc/blocks.h"
+#include "libvpsc/solve_VPSC.h"
+#include "libvpsc/cbuffer.h"
+#include "libvpsc/variable.h"
+#include "libvpsc/assertions.h"
+#include "libvpsc/exceptions.h"
+
+#ifdef LIBVPSC_LOGGING
+#include <fstream>
+#endif
+
+using namespace std;
+
+namespace vpsc {
+
+static const double ZERO_UPPERBOUND=-1e-10;
+static const double LAGRANGIAN_TOLERANCE=-1e-4;
+
+IncSolver::IncSolver(Variables const &vs, Constraints const &cs)
+ : Solver(vs,cs)
+{
+ inactive=cs;
+ for(Constraints::iterator i=inactive.begin();i!=inactive.end();++i) {
+ (*i)->active=false;
+ }
+}
+Solver::Solver(Variables const &vs, Constraints const &cs)
+ : m(cs.size()),
+ cs(cs),
+ n(vs.size()),
+ vs(vs),
+ needsScaling(false)
+{
+ for(unsigned i=0;i<n;++i) {
+ vs[i]->in.clear();
+ vs[i]->out.clear();
+
+ // Set needsScaling if any variables have a scale other than 1.
+ needsScaling |= (vs[i]->scale != 1);
+ }
+ for(unsigned i=0;i<m;++i) {
+ Constraint *c=cs[i];
+ c->left->out.push_back(c);
+ c->right->in.push_back(c);
+ c->needsScaling = needsScaling;
+ }
+ bs=new Blocks(vs);
+#ifdef LIBVPSC_LOGGING
+ printBlocks();
+ //COLA_ASSERT(!constraintGraphIsCyclic(n,vs));
+#endif
+}
+Solver::~Solver() {
+ delete bs;
+}
+
+void IncSolver::addConstraint(Constraint *c)
+{
+ ++m;
+ c->active = false;
+ inactive.push_back(c);
+ c->left->out.push_back(c);
+ c->right->in.push_back(c);
+ c->needsScaling = needsScaling;
+}
+
+// useful in debugging
+void Solver::printBlocks() {
+#ifdef LIBVPSC_LOGGING
+ ofstream f(LOGFILE,ios::app);
+ for(set<Block*>::iterator i=bs->begin();i!=bs->end();++i) {
+ Block *b=*i;
+ f<<" "<<*b<<endl;
+ }
+ for(unsigned i=0;i<m;i++) {
+ f<<" "<<*cs[i]<<endl;
+ }
+#endif
+}
+
+/**
+ * Stores the relative positions of the variables in their finalPosition
+ * field.
+ */
+void Solver::copyResult() {
+ for(Variables::const_iterator i=vs.begin();i!=vs.end();++i) {
+ Variable* v=*i;
+ v->finalPosition=v->position();
+ COLA_ASSERT(v->finalPosition==v->finalPosition);
+ }
+}
+/**
+* Produces a feasible - though not necessarily optimal - solution by
+* examining blocks in the partial order defined by the directed acyclic
+* graph of constraints. For each block (when processing left to right) we
+* maintain the invariant that all constraints to the left of the block
+* (incoming constraints) are satisfied. This is done by repeatedly merging
+* blocks into bigger blocks across violated constraints (most violated
+* first) fixing the position of variables inside blocks relative to one
+* another so that constraints internal to the block are satisfied.
+*/
+bool Solver::satisfy() {
+ list<Variable*> *vList=bs->totalOrder();
+ for(list<Variable*>::iterator i=vList->begin();i!=vList->end();++i) {
+ Variable *v=*i;
+ if(!v->block->deleted) {
+ bs->mergeLeft(v->block);
+ }
+ }
+ bs->cleanup();
+ bool activeConstraints=false;
+ for(unsigned i=0;i<m;i++) {
+ if(cs[i]->active) activeConstraints=true;
+ if(cs[i]->slack() < ZERO_UPPERBOUND) {
+#ifdef LIBVPSC_LOGGING
+ ofstream f(LOGFILE,ios::app);
+ f<<"Error: Unsatisfied constraint: "<<*cs[i]<<endl;
+#endif
+ //COLA_ASSERT(cs[i]->slack()>-0.0000001);
+ throw UnsatisfiedConstraint(*cs[i]);
+ }
+ }
+ delete vList;
+ copyResult();
+ return activeConstraints;
+}
+
+void Solver::refine() {
+ bool solved=false;
+ // Solve shouldn't loop indefinately
+ // ... but just to make sure we limit the number of iterations
+ unsigned maxtries=100;
+ while(!solved&&maxtries>0) {
+ solved=true;
+ maxtries--;
+ size_t length = bs->size();
+ for (size_t i = 0; i < length; ++i)
+ {
+ Block *b = bs->at(i);
+ b->setUpInConstraints();
+ b->setUpOutConstraints();
+ }
+ for (size_t i = 0; i < length; ++i)
+ {
+ Block *b = bs->at(i);
+ Constraint *c=b->findMinLM();
+ if(c!=nullptr && c->lm<LAGRANGIAN_TOLERANCE) {
+#ifdef LIBVPSC_LOGGING
+ ofstream f(LOGFILE,ios::app);
+ f<<"Split on constraint: "<<*c<<endl;
+#endif
+ // Split on c
+ Block *l=nullptr, *r=nullptr;
+ bs->split(b,l,r,c);
+ bs->cleanup();
+ // split alters the block set so we have to restart
+ solved=false;
+ break;
+ }
+ }
+ }
+ for(unsigned i=0;i<m;i++) {
+ if(cs[i]->slack() < ZERO_UPPERBOUND) {
+ COLA_ASSERT(cs[i]->slack()>ZERO_UPPERBOUND);
+ throw UnsatisfiedConstraint(*cs[i]);
+ }
+ }
+}
+/**
+ * Calculate the optimal solution. After using satisfy() to produce a
+ * feasible solution, refine() examines each block to see if further
+ * refinement is possible by splitting the block. This is done repeatedly
+ * until no further improvement is possible.
+ */
+bool Solver::solve() {
+ satisfy();
+ refine();
+ copyResult();
+ return bs->size()!=n;
+}
+
+bool IncSolver::solve() {
+#ifdef LIBVPSC_LOGGING
+ ofstream f(LOGFILE,ios::app);
+ f<<"solve_inc()..."<<endl;
+#endif
+ satisfy();
+ double lastcost = DBL_MAX, cost = bs->cost();
+ while(fabs(lastcost-cost)>0.0001) {
+ satisfy();
+ lastcost=cost;
+ cost = bs->cost();
+#ifdef LIBVPSC_LOGGING
+ f<<" bs->size="<<bs->size()<<", cost="<<cost<<endl;
+#endif
+ }
+ copyResult();
+ return bs->size()!=n;
+}
+/**
+ * incremental version of satisfy that allows refinement after blocks are
+ * moved.
+ *
+ * - move blocks to new positions
+ * - repeatedly merge across most violated constraint until no more
+ * violated constraints exist
+ *
+ * Note: there is a special case to handle when the most violated constraint
+ * is between two variables in the same block. Then, we must split the block
+ * over an active constraint between the two variables. We choose the
+ * constraint with the most negative lagrangian multiplier.
+ */
+bool IncSolver::satisfy() {
+#ifdef LIBVPSC_LOGGING
+ ofstream f(LOGFILE,ios::app);
+ f<<"satisfy_inc()..."<<endl;
+#endif
+ splitBlocks();
+ //long splitCtr = 0;
+ Constraint* v = nullptr;
+ //CBuffer buffer(inactive);
+ while ( (v = mostViolated(inactive)) &&
+ (v->equality || ((v->slack() < ZERO_UPPERBOUND) && !v->active)) )
+ {
+ COLA_ASSERT(!v->active);
+ Block *lb = v->left->block, *rb = v->right->block;
+ if(lb != rb) {
+ lb->merge(rb,v);
+ } else {
+ if(lb->isActiveDirectedPathBetween(v->right,v->left)) {
+ // cycle found, relax the violated, cyclic constraint
+ v->unsatisfiable=true;
+ continue;
+ //UnsatisfiableException e;
+ //lb->getActiveDirectedPathBetween(e.path,v->right,v->left);
+ //e.path.push_back(v);
+ //throw e;
+ }
+ //if(splitCtr++>10000) {
+ //throw "Cycle Error!";
+ //}
+ // constraint is within block, need to split first
+ try {
+ Constraint* splitConstraint
+ =lb->splitBetween(v->left,v->right,lb,rb);
+ if(splitConstraint!=nullptr) {
+ COLA_ASSERT(!splitConstraint->active);
+ inactive.push_back(splitConstraint);
+ } else {
+ v->unsatisfiable=true;
+ continue;
+ }
+ } catch(UnsatisfiableException e) {
+ e.path.push_back(v);
+#ifdef LIBVPSC_DEBUG
+ std::cerr << "Unsatisfiable:" << std::endl;
+ for(std::vector<Constraint*>::iterator r=e.path.begin();
+ r!=e.path.end();++r)
+ {
+ std::cerr << **r <<std::endl;
+ }
+#endif
+ v->unsatisfiable=true;
+ continue;
+ }
+ if(v->slack()>=0) {
+ COLA_ASSERT(!v->active);
+ // v was satisfied by the above split!
+ inactive.push_back(v);
+ bs->insert(lb);
+ bs->insert(rb);
+ } else {
+ bs->insert(lb->merge(rb,v));
+ delete ((lb->deleted) ? lb : rb);
+ }
+ }
+#ifdef LIBVPSC_LOGGING
+ f<<"...remaining blocks="<<bs->size()<<", cost="<<bs->cost()<<endl;
+#endif
+ }
+#ifdef LIBVPSC_LOGGING
+ f<<" finished merges."<<endl;
+#endif
+ bs->cleanup();
+ bool activeConstraints=false;
+ for(unsigned i=0;i<m;i++) {
+ v=cs[i];
+ if(v->active) activeConstraints=true;
+ if(v->slack() < ZERO_UPPERBOUND) {
+ ostringstream s;
+ s<<"Unsatisfied constraint: "<<*v;
+#ifdef LIBVPSC_LOGGING
+ ofstream f(LOGFILE,ios::app);
+ f<<s.str()<<endl;
+#endif
+ throw (char *) s.str().c_str();
+ }
+ }
+#ifdef LIBVPSC_LOGGING
+ f<<" finished cleanup."<<endl;
+ printBlocks();
+#endif
+ copyResult();
+ return activeConstraints;
+}
+void IncSolver::moveBlocks() {
+#ifdef LIBVPSC_LOGGING
+ ofstream f(LOGFILE,ios::app);
+ f<<"moveBlocks()..."<<endl;
+#endif
+ size_t length = bs->size();
+ for (size_t i = 0; i < length; ++i)
+ {
+ Block *b = bs->at(i);
+ b->updateWeightedPosition();
+ //b->posn = b->wposn / b->weight;
+ }
+#ifdef LIBVPSC_LOGGING
+ f<<" moved blocks."<<endl;
+#endif
+}
+void IncSolver::splitBlocks() {
+#ifdef LIBVPSC_LOGGING
+ ofstream f(LOGFILE,ios::app);
+#endif
+ moveBlocks();
+ splitCnt=0;
+ // Split each block if necessary on min LM
+ size_t length = bs->size();
+ for (size_t i = 0; i < length; ++i)
+ {
+ Block *b = bs->at(i);
+ Constraint* v=b->findMinLM();
+ if(v!=nullptr && v->lm < LAGRANGIAN_TOLERANCE) {
+ COLA_ASSERT(!v->equality);
+#ifdef LIBVPSC_LOGGING
+ f<<" found split point: "<<*v<<" lm="<<v->lm<<endl;
+#endif
+ splitCnt++;
+ Block *b = v->left->block, *l=nullptr, *r=nullptr;
+ COLA_ASSERT(v->left->block == v->right->block);
+ //double pos = b->posn;
+ b->split(l,r,v);
+ //l->posn=r->posn=pos;
+ //l->wposn = l->posn * l->weight;
+ //r->wposn = r->posn * r->weight;
+ l->updateWeightedPosition();
+ r->updateWeightedPosition();
+ bs->insert(l);
+ bs->insert(r);
+ b->deleted=true;
+ COLA_ASSERT(!v->active);
+ inactive.push_back(v);
+#ifdef LIBVPSC_LOGGING
+ f<<" new blocks: "<<*l<<" and "<<*r<<endl;
+#endif
+ }
+ }
+ //if(splitCnt>0) { std::cout<<" splits: "<<splitCnt<<endl; }
+#ifdef LIBVPSC_LOGGING
+ f<<" finished splits."<<endl;
+#endif
+ bs->cleanup();
+}
+
+/**
+ * Scan constraint list for the most violated constraint, or the first equality
+ * constraint
+ */
+Constraint* IncSolver::mostViolated(Constraints &l)
+{
+ double slackForMostViolated = DBL_MAX;
+ Constraint* mostViolated = nullptr;
+#ifdef LIBVPSC_LOGGING
+ ofstream f(LOGFILE,ios::app);
+ f << "Looking for most violated..." << endl;
+#endif
+ size_t lSize = l.size();
+ size_t deleteIndex = lSize;
+ Constraint *constraint = nullptr;
+ double slack = 0;
+ for (size_t index = 0; index < lSize; ++index)
+ {
+ constraint = l[index];
+ slack = constraint->slack();
+ if (constraint->equality || slack < slackForMostViolated)
+ {
+ slackForMostViolated = slack;
+ mostViolated = constraint;
+ deleteIndex = index;
+ if (constraint->equality)
+ {
+ break;
+ }
+ }
+ }
+ // Because the constraint list is not order dependent we just
+ // move the last element over the deletePoint and resize
+ // downwards. There is always at least 1 element in the
+ // vector because of search.
+ if ( (deleteIndex < lSize) &&
+ (((slackForMostViolated < ZERO_UPPERBOUND) && !mostViolated->active) ||
+ mostViolated->equality) )
+ {
+ l[deleteIndex] = l[lSize-1];
+ l.resize(lSize-1);
+ }
+#ifdef LIBVPSC_LOGGING
+ if (mostViolated)
+ {
+ f << " most violated is: " << *mostViolated << endl;
+ }
+ else
+ {
+ f << " non found." << endl;
+ }
+#endif
+ return mostViolated;
+}
+
+struct node {
+ set<node*> in;
+ set<node*> out;
+};
+// useful in debugging - cycles would be BAD
+bool Solver::constraintGraphIsCyclic(const unsigned n, Variable* const vs[]) {
+ map<Variable*, node*> varmap;
+ vector<node*> graph;
+ for(unsigned i=0;i<n;i++) {
+ node *u=new node;
+ graph.push_back(u);
+ varmap[vs[i]]=u;
+ }
+ for(unsigned i=0;i<n;i++) {
+ for(vector<Constraint*>::iterator c=vs[i]->in.begin();c!=vs[i]->in.end();++c) {
+ Variable *l=(*c)->left;
+ varmap[vs[i]]->in.insert(varmap[l]);
+ }
+
+ for(vector<Constraint*>::iterator c=vs[i]->out.begin();c!=vs[i]->out.end();++c) {
+ Variable *r=(*c)->right;
+ varmap[vs[i]]->out.insert(varmap[r]);
+ }
+ }
+ while(graph.size()>0) {
+ node *u=nullptr;
+ vector<node*>::iterator i=graph.begin();
+ for(;i!=graph.end();++i) {
+ u=*i;
+ if(u->in.size()==0) {
+ break;
+ }
+ }
+ if(i==graph.end() && graph.size()>0) {
+ //cycle found!
+ return true;
+ } else {
+ graph.erase(i);
+ for(set<node*>::iterator j=u->out.begin();j!=u->out.end();++j) {
+ node *v=*j;
+ v->in.erase(u);
+ }
+ delete u;
+ }
+ }
+ for(unsigned i=0; i<graph.size(); ++i) {
+ delete graph[i];
+ }
+ return false;
+}
+
+// useful in debugging - cycles would be BAD
+bool Solver::blockGraphIsCyclic() {
+ map<Block*, node*> bmap;
+ vector<node*> graph;
+ size_t length = bs->size();
+ for (size_t i = 0; i < length; ++i)
+ {
+ Block *b = bs->at(i);
+ node *u=new node;
+ graph.push_back(u);
+ bmap[b]=u;
+ }
+ for (size_t i = 0; i < length; ++i)
+ {
+ Block *b = bs->at(i);
+ b->setUpInConstraints();
+ Constraint *c=b->findMinInConstraint();
+ while(c!=nullptr) {
+ Block *l=c->left->block;
+ bmap[b]->in.insert(bmap[l]);
+ b->deleteMinInConstraint();
+ c=b->findMinInConstraint();
+ }
+
+ b->setUpOutConstraints();
+ c=b->findMinOutConstraint();
+ while(c!=nullptr) {
+ Block *r=c->right->block;
+ bmap[b]->out.insert(bmap[r]);
+ b->deleteMinOutConstraint();
+ c=b->findMinOutConstraint();
+ }
+ }
+ while(graph.size()>0) {
+ node *u=nullptr;
+ vector<node*>::iterator i=graph.begin();
+ for(;i!=graph.end();++i) {
+ u=*i;
+ if(u->in.size()==0) {
+ break;
+ }
+ }
+ if(i==graph.end() && graph.size()>0) {
+ //cycle found!
+ return true;
+ } else {
+ graph.erase(i);
+ for(set<node*>::iterator j=u->out.begin();j!=u->out.end();++j) {
+ node *v=*j;
+ v->in.erase(u);
+ }
+ delete u;
+ }
+ }
+ for(unsigned i=0; i<graph.size(); i++) {
+ delete graph[i];
+ }
+ return false;
+}
+}
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