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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-13 11:57:42 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-13 11:57:42 +0000 |
commit | 61f3ab8f23f4c924d455757bf3e65f8487521b5a (patch) | |
tree | 885599a36a308f422af98616bc733a0494fe149a /src/toys/curve-curve-nearest-time.cpp | |
parent | Initial commit. (diff) | |
download | lib2geom-61f3ab8f23f4c924d455757bf3e65f8487521b5a.tar.xz lib2geom-61f3ab8f23f4c924d455757bf3e65f8487521b5a.zip |
Adding upstream version 1.3.upstream/1.3upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/toys/curve-curve-nearest-time.cpp')
-rw-r--r-- | src/toys/curve-curve-nearest-time.cpp | 609 |
1 files changed, 609 insertions, 0 deletions
diff --git a/src/toys/curve-curve-nearest-time.cpp b/src/toys/curve-curve-nearest-time.cpp new file mode 100644 index 0000000..30fb327 --- /dev/null +++ b/src/toys/curve-curve-nearest-time.cpp @@ -0,0 +1,609 @@ +/* + * Nearest Points Toy 3 + * + * Authors: + * Nathan Hurst <njh at njhurst.com> + * Marco Cecchetti <mrcekets at gmail.com> + * + * Copyright 2008 authors + * + * This library is free software; you can redistribute it and/or + * modify it either under the terms of the GNU Lesser General Public + * License version 2.1 as published by the Free Software Foundation + * (the "LGPL") or, at your option, under the terms of the Mozilla + * Public License Version 1.1 (the "MPL"). If you do not alter this + * notice, a recipient may use your version of this file under either + * the MPL or the LGPL. + * + * You should have received a copy of the LGPL along with this library + * in the file COPYING-LGPL-2.1; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * You should have received a copy of the MPL along with this library + * in the file COPYING-MPL-1.1 + * + * The contents of this file are subject to the Mozilla Public License + * Version 1.1 (the "License"); you may not use this file except in + * compliance with the License. You may obtain a copy of the License at + * http://www.mozilla.org/MPL/ + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY + * OF ANY KIND, either express or implied. See the LGPL or the MPL for + * the specific language governing rights and limitations. + */ + + +#include <2geom/d2.h> +#include <2geom/sbasis.h> +#include <2geom/path.h> +#include <2geom/bezier-to-sbasis.h> +#include <2geom/sbasis-geometric.h> +#include <2geom/piecewise.h> +#include <2geom/path-intersection.h> + +#include <toys/path-cairo.h> +#include <toys/toy-framework-2.h> + +#include <algorithm> + + +using namespace Geom; + + +class np_finder +{ +public: + np_finder(cairo_t* _cr, D2<SBasis> const& _c1, D2<SBasis> const& _c2) + : cr(_cr), cc1(_c1), cc2(_c2), c1(_c1), c2(_c2) + { + + dc1 = derivative(_c1); + dc2 = derivative(_c2); + cd1 = dot(_c1,dc1); + cd2 = dot(_c2,dc2); + dsq = 10e30; + + Piecewise< D2<SBasis> > uv1 = unitVector(dc1, EPSILON); + Piecewise< D2<SBasis> > uv2 = unitVector(dc2, EPSILON); + + dcn1 = dot(Piecewise< D2<SBasis> >(dc1), uv1); + dcn2 = dot(Piecewise< D2<SBasis> >(dc2), uv2); + + r_dcn1 = cross(derivative(uv1), uv1); + r_dcn2 = cross(derivative(uv2), uv2); + + k1 = Geom::divide(r_dcn1, dcn1, EPSILON, 3); + k2 = Geom::divide(r_dcn2, dcn2, EPSILON, 3); + + + n1 = divide(rot90(uv1), k1, EPSILON, 3); + n2 = divide(rot90(uv2), k2, EPSILON, 3); + + std::vector<double> cuts1, cuts2; + + // add cuts at points where the curvature is discontinuos + for ( unsigned int i = 1; i < k1.size(); ++i ) + { + if( !are_near(k1[i-1].at1(), k1[i].at0()) ) + { + cuts1.push_back(k1.cuts[i]); + } + } + for ( unsigned int i = 1; i < k2.size(); ++i ) + { + if( !are_near(k2[i-1].at1(), k2[i].at0()) ) + { + cuts2.push_back(k2.cuts[i]); + } + } + + c1 = partition(c1, cuts1); + c2 = partition(c2, cuts2); + +// std::cerr << "# k1 discontinuitis" << std::endl; +// for( unsigned int i = 0; i < cuts1.size(); ++i ) +// { +// std::cerr << "[" << i << "]= " << cuts1[i] << std::endl; +// } +// std::cerr << "# k2 discontinuitis" << std::endl; +// for( unsigned int i = 0; i < cuts2.size(); ++i ) +// { +// std::cerr << "[" << i << "]= " << cuts2[i] << std::endl; +// } + + // add cuts at points were the curvature is zero + std::vector<double> k1_roots = roots(k1); + std::vector<double> k2_roots = roots(k2); + std::sort(k1_roots.begin(), k1_roots.end()); + std::sort(k2_roots.begin(), k2_roots.end()); + c1 = partition(c1, k1_roots); + c2 = partition(c2, k2_roots); + +// std::cerr << "# k1 zeros" << std::endl; +// for( unsigned int i = 0; i < k1_roots.size(); ++i ) +// { +// std::cerr << "[" << i << "]= " << k1_roots[i] << std::endl; +// } +// std::cerr << "# k2 zeros" << std::endl; +// for( unsigned int i = 0; i < k2_roots.size(); ++i ) +// { +// std::cerr << "[" << i << "]= " << k2_roots[i] << std::endl; +// } + + + cairo_set_line_width(cr, 0.2); +// cairo_set_source_rgba(cr, 0.0, 0.5, 0.0, 1.0); +// for( unsigned int i = 1; i < c1.size(); ++i ) +// { +// draw_circ(cr, c1[i].at0() ); +// } +// for( unsigned int i = 1; i < c2.size(); ++i ) +// { +// draw_circ(cr, c2[i].at0() ); +// } + + + // add cuts at nearest points to the other curve cuts points + cuts1.clear(); + cuts1.reserve(c1.size()+1); + for ( unsigned int i = 0; i < c1.size(); ++i ) + { + cuts1.push_back( nearest_time(c1[i].at0(), _c2, dc2, cd2) ); + } + cuts1.push_back( nearest_time(c1[c1.size()-1].at1(), _c2, dc2, cd2) ); + +// for ( unsigned int i = 0; i < c1.size(); ++i ) +// { +// cairo_move_to( cr, c1[i].at0() ); +// cairo_line_to(cr, c2(cuts1[i]) ); +// } +// cairo_move_to( cr, c1[c1.size()-1].at1() ); +// cairo_line_to(cr, c2(cuts1[c1.size()])); + + std::sort(cuts1.begin(), cuts1.end()); + + cuts2.clear(); + cuts2.reserve(c2.size()+1); + for ( unsigned int i = 0; i < c2.size(); ++i ) + { + cuts2.push_back( nearest_time(c2[i].at0(), _c1, dc1, cd1) ); + } + cuts2.push_back( nearest_time(c2[c2.size()-1].at1(), _c1, dc1, cd1) ); + +// for ( unsigned int i = 0; i < c2.size(); ++i ) +// { +// cairo_move_to( cr, c2[i].at0() ); +// cairo_line_to(cr, c1(cuts2[i]) ); +// } +// cairo_move_to( cr, c2[c2.size()-1].at1() ); +// cairo_line_to(cr, c1(cuts2[c2.size()])); +// cairo_stroke(cr); + + std::sort(cuts2.begin(), cuts2.end()); + + c1 = partition(c1, cuts2); + c2 = partition(c2, cuts1); + + + // copy curve to preserve cuts status + Piecewise< D2<SBasis> > pwc1 = c1; + n1 = partition(n1, pwc1.cuts); + pwc1 = partition(pwc1, n1.cuts); + r_dcn1 = partition(r_dcn1, n1.cuts); + Piecewise< D2<SBasis> > pwc2 = c2; + n2 = partition(n2, pwc2.cuts); + pwc2 = partition(pwc2, n2.cuts); + + assert( pwc1.size() == n1.size() ); + assert( pwc2.size() == n2.size() ); + assert( r_dcn1.size() == n1.size() ); + + // add cuts at curvature max and min points + Piecewise<SBasis> dk1 = derivative(k1); + Piecewise<SBasis> dk2 = derivative(k2); + std::vector<double> dk1_roots = roots(dk1); + std::vector<double> dk2_roots = roots(dk2); + std::sort(dk1_roots.begin(), dk1_roots.end()); + std::sort(dk2_roots.begin(), dk2_roots.end()); + + c1 = partition(c1, dk1_roots); + c2 = partition(c2, dk2_roots); + +// std::cerr << "# k1 min/max" << std::endl; +// for( unsigned int i = 0; i < dk1_roots.size(); ++i ) +// { +// std::cerr << "[" << i << "]= " << dk1_roots[i] << std::endl; +// } +// std::cerr << "# k2 min/max" << std::endl; +// for( unsigned int i = 0; i < dk2_roots.size(); ++i ) +// { +// std::cerr << "[" << i << "]= " << dk2_roots[i] << std::endl; +// } + +// cairo_set_source_rgba(cr, 0.0, 0.0, 0.6, 1.0); +// for( unsigned int i = 0; i < dk1_roots.size(); ++i ) +// { +// draw_handle(cr, c1(dk1_roots[i])); +// } +// for( unsigned int i = 0; i < dk2_roots.size(); ++i ) +// { +// draw_handle(cr, c2(dk2_roots[i])); +// } + + + // add cuts at nearest points to max and min curvature points + // of the other curve + cuts1.clear(); + cuts1.reserve(dk2_roots.size()); + for (double dk2_root : dk2_roots) + { + cuts1.push_back(nearest_time(_c2(dk2_root), _c1, dc1, cd1)); + } + +// for( unsigned int i = 0; i < dk2_roots.size(); ++i ) +// { +// cairo_move_to(cr, c2(dk2_roots[i])); +// cairo_line_to(cr, c1(cuts1[i])); +// } +// cairo_stroke(cr); + + std::sort(cuts1.begin(), cuts1.end()); + c1 = partition(c1, cuts1); + + + // swap normal vector direction and fill the skip list + skip_list.clear(); + skip_list.resize(c1.size(), false); + double npt; + Point p, nv; + unsigned int si; + for ( unsigned int i = 0; i < pwc1.size(); ++i ) + { + p = pwc1[i](0.5); + nv = n1[i](0.5); + npt = nearest_time(p, _c2, dc2, cd2); + if( dot( _c2(npt) - p, nv ) > 0 ) + { + if ( dot( nv, n2(npt) ) > 0 ) + { + n1[i] = -n1[i]; + r_dcn1[i] = -r_dcn1[i]; + } + else + { + si = c1.segN( n1.mapToDomain(0.5, i) ); + skip_list[si] = true; + } + } + } + + + for ( unsigned int i = 0; i < pwc2.size(); ++i ) + { + p = pwc2[i](0.5); + nv = n2[i](0.5); + npt = nearest_time(p, _c1, dc1, cd1); + if( dot( _c1(npt) - p, nv ) > 0 ) + { + if ( dot( nv, n1(npt) ) > 0 ) + { + n2[i] = -n2[i]; + } + } + } + + + evl1 = c1 + n1; + evl2 = c2 + n2; + +// cairo_set_source_rgba(cr, 0.3, 0.3, 0.3, 1.0); +// for ( unsigned int i = 0; i < c1.size(); ++i ) +// { +// double t = c1.mapToDomain(0.5, i); +// cairo_move_to(cr, c1(t)); +// cairo_line_to(cr, c1(t) + 30*unit_vector(n1(t))); +// } +// +// for ( unsigned int i = 0; i < c2.size(); ++i ) +// { +// double t = c2.mapToDomain(0.5, i); +// cairo_move_to(cr, c2(t)); +// cairo_line_to(cr, c2(t) + 30*unit_vector(n2(t))); +// } +// cairo_stroke(cr); + + std::cerr << "# skip list: "; + for( unsigned int i = 0; i < c1.cuts.size(); ++i ) + { + if ( skip_list[i] ) + std::cerr << i << " "; + } + std::cerr << std::endl; + + cairo_set_line_width(cr, 0.4); + cairo_set_source_rgba(cr, 0.6, 0.0, 0.0, 1.0); + for( unsigned int i = 0; i < c1.size(); ++i ) + { + if ( skip_list[i] ) + { + cairo_move_to(cr, c1[i].at0()); + cairo_line_to(cr, c1[i].at1()); + } + } + cairo_stroke(cr); + + cairo_set_source_rgba(cr, 0.2, 0.2, 0.2, 1.0); + for( unsigned int i = 1; i < c1.size(); ++i ) + { + draw_circ(cr, c1[i].at0() ); + } + cairo_stroke(cr); + + std::cerr << "# c1 cuts: " << std::endl; + for( unsigned int i = 0; i < c1.cuts.size(); ++i ) + { + std::cerr << "c1.cuts[" << i << "]= " << c1.cuts[i] << std::endl; + } + + } + + void operator() () + { + nearest_times_impl(); + d = sqrt(dsq); + } + + Point firstPoint() const + { + return p1; + } + + Point secondPoint() const + { + return p2; + } + + double firstValue() const + { + return t1; + } + + double secondValue() const + { + return t2; + } + + double distance() const + { + return d; + } + +private: + void nearest_times_impl() + { + double t; + for ( unsigned int i = 0; i < c1.size(); ++i ) + { + if ( skip_list[i] ) continue; + std::cerr << i << " "; + t = c1.mapToDomain(0.5, i); + std::pair<double, double> npc = loc_nearest_times(t, c1.cuts[i], c1.cuts[i+1]); + if ( npc.second != -1 && dsq > L2sq(c1(npc.first) - c2(npc.second)) ) + { + t1 = npc.first; + t2 = npc.second; + p1 = c1(t1); + p2 = c2(t2); + dsq = L2sq(p1 - p2); + } + } + } + + std::pair<double, double> + loc_nearest_times( double t, double from = 0, double to = 1 ) + { + std::cerr << "[" << from << "," << to << "] t: " << t << std::endl; + unsigned int iter = 0, iter1 = 0, iter2 = 0; + std::pair<double, double> np(-1,-1); + std::pair<double, double> npf(from, -1); + std::pair<double, double> npt(to, -1); + double ct = t; + double pt = -1; + double s = nearest_time(c1(t), cc2, dc2, cd2); + cairo_set_source_rgba(cr, 1/(t+1), t*t, t, 1.0); + cairo_move_to(cr, c1(t)); + while( !are_near(ct, pt) && iter < 1000 ) + { + pt = ct; + double angle = angle_between( n1(ct), evl2(s) - evl1(ct) ); + assert( !std::isnan(angle) ); + angle = (angle > 0) ? angle - M_PI : angle + M_PI; + if ( std::fabs(angle) < M_PI/12 ) + { + ++iter2; +// cairo_move_to(cr, c1(ct)); +// cairo_line_to(cr, evl1(ct)); +// cairo_line_to(cr, evl2(s)); + //std::cerr << "s: " << s << std::endl; + //std::cerr << "t: " << ct << std::endl; + + ct = ct + angle / r_dcn1(ct); + s = nearest_time(c1(ct), cc2, dc2, cd2); +// angle = angle_between( n2(s), evl1(ct) - evl2(s) ); +// assert( !std::isnan(angle) ); +// angle = (angle > 0) ? angle - M_PI : angle + M_PI; +// s = s + angle / (dcn2(s) * k2(s)); + } + else + { + ++iter1; + ct = nearest_time(c2(s), cc1, dc1, cd1, from, to); + s = nearest_time(c1(ct), cc2, dc2, cd2); + } + iter = iter1 + iter2; + //std::cerr << "s: " << s << std::endl; + //std::cerr << "t: " << ct << std::endl; + //cairo_line_to(cr, c2(s)); + //cairo_line_to(cr, c1(ct)); + //std::cerr << "d(pt, ct) = " << std::fabs(ct - pt) << std::endl; + if ( ct < from ) + { + std::cerr << "break left" << std::endl; + np = npf; + break; + } + if ( ct > to ) + { + std::cerr << "break right" << std::endl; + np =npt; + break; + } + } + //std::cerr << "\n \n"; + std::cerr << "iterations: " << iter1 << " + " << iter2 << " = "<< iter << std::endl; + assert(iter < 3000); + //cairo_move_to(cr, c1(ct)); + //cairo_line_to(cr, c2(s)); + cairo_stroke(cr); + np.first = ct; + np.second = s; + return np; + } + + double nearest_time( Point const& p, D2<SBasis> const&c, D2<SBasis> const& dc, SBasis const& cd, double from = 0, double to = 1 ) + { + D2<SBasis> sbc = c - p; + SBasis dd = cd - dotp(p, dc); + std::vector<double> zeros = roots(dd); + double closest = from; + double distsq = L2sq(sbc(from)); + for (double zero : zeros) + { + if ( distsq > L2sq(sbc(zero)) ) + { + closest = zero; + distsq = L2sq(sbc(closest)); + } + } + if ( distsq > L2sq(sbc(to)) ) + closest = to; + return closest; + } + + SBasis dotp(Point const& p, D2<SBasis> const& c) + { + SBasis d; + d.resize(c[X].size()); + for ( unsigned int i = 0; i < c[0].size(); ++i ) + { + for( unsigned int j = 0; j < 2; ++j ) + d[i][j] = p[X] * c[X][i][j] + p[Y] * c[Y][i][j]; + } + return d; + } + + Piecewise< D2<SBasis> > + divide( Piecewise< D2<SBasis> > const& a, Piecewise<SBasis> const& b, double tol, unsigned int k, double zero=1.e-3) + { + D2< Piecewise<SBasis> > aa = make_cuts_independent(a); + D2< Piecewise<SBasis> > q(Geom::divide(aa[0], b, tol, k, zero), Geom::divide(aa[1], b, tol, k, zero)); + return sectionize(q); + } + + struct are_near_ + { + bool operator() (double x, double y, double eps = Geom::EPSILON ) + { + return are_near(x, y, eps); + } + }; + +private: + cairo_t* cr; + D2<SBasis> const& cc1, cc2; + Piecewise< D2<SBasis> > c1, c2; + D2<SBasis> dc1, dc2; + SBasis cd1, cd2; + Piecewise< D2<SBasis> > n1, n2, evl1, evl2; + Piecewise<SBasis> k1, k2, dcn1, dcn2, r_dcn1, r_dcn2; + double t1, t2, d, dsq; + Point p1, p2; + std::vector<bool> skip_list; +}; + + + + +class NearestPoints : public Toy +{ + private: + void draw( cairo_t *cr, std::ostringstream *notify, + int width, int height, bool save, std::ostringstream *timer_stream) override + { + cairo_set_line_width (cr, 0.3); + D2<SBasis> A = pshA.asBezier(); + cairo_d2_sb(cr, A); + D2<SBasis> B = pshB.asBezier(); + cairo_d2_sb(cr, B); + cairo_stroke(cr); + + np_finder np(cr, A, B); + Path AP, BP; + AP.append(A); BP.append(B); + Crossings ip_list = curve_sweep<SimpleCrosser>(AP, BP); + if( ip_list.empty() ) + { + np(); + cairo_set_line_width (cr, 0.4); + cairo_set_source_rgba(cr, 0.7, 0.0, 0.7, 1.0); + cairo_move_to(cr, np.firstPoint()); + cairo_line_to(cr, np.secondPoint()); + cairo_stroke(cr); + //std::cerr << "np: (" << np.firstValue() << "," << np.secondValue() << ")" << std::endl; + } + Toy::draw(cr, notify, width, height, save,timer_stream); + } + + public: + NearestPoints(unsigned int _A_bez_ord, unsigned int _B_bez_ord) + : A_bez_ord(_A_bez_ord), B_bez_ord(_B_bez_ord) + { + handles.push_back(&pshA); + handles.push_back(&pshB); + for ( unsigned int i = 0; i < A_bez_ord; ++i ) + pshA.push_back(Geom::Point(uniform()*400, uniform()*400)); + for ( unsigned int i = 0; i < B_bez_ord; ++i ) + pshB.push_back(Geom::Point(uniform()*400, uniform()*400)); + + } + + private: + PointSetHandle pshA, pshB; + unsigned int A_bez_ord; + unsigned int B_bez_ord; +}; + + +int main(int argc, char **argv) +{ + unsigned int A_bez_ord=8; + unsigned int B_bez_ord=5; + if(argc > 2) + sscanf(argv[2], "%d", &B_bez_ord); + if(argc > 1) + sscanf(argv[1], "%d", &A_bez_ord); + + init( argc, argv, new NearestPoints(A_bez_ord, B_bez_ord)); + return 0; +} + + +/* + Local Variables: + mode:c++ + c-file-style:"stroustrup" + c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +)) + indent-tabs-mode:nil + fill-column:99 + End: +*/ +// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 : |