diff --git a/test/planarity_test.cc b/test/planarity_test.cc new file mode 100644 --- /dev/null +++ b/test/planarity_test.cc @@ -0,0 +1,259 @@ +/* -*- mode: C++; indent-tabs-mode: nil; -*- + * + * This file is a part of LEMON, a generic C++ optimization library. + * + * Copyright (C) 2003-2009 + * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport + * (Egervary Research Group on Combinatorial Optimization, EGRES). + * + * Permission to use, modify and distribute this software is granted + * provided that this copyright notice appears in all copies. For + * precise terms see the accompanying LICENSE file. + * + * This software is provided "AS IS" with no warranty of any kind, + * express or implied, and with no claim as to its suitability for any + * purpose. + * + */ + +#include + +#include + +#include +#include +#include +#include + +#include "test_tools.h" + +using namespace lemon; +using namespace lemon::dim2; + +const int lgfn = 4; +const std::string lgf[lgfn] = { + "@nodes\n" + "label\n" + "0\n" + "1\n" + "2\n" + "3\n" + "4\n" + "@edges\n" + " label\n" + "0 1 0\n" + "0 2 0\n" + "0 3 0\n" + "0 4 0\n" + "1 2 0\n" + "1 3 0\n" + "1 4 0\n" + "2 3 0\n" + "2 4 0\n" + "3 4 0\n", + + "@nodes\n" + "label\n" + "0\n" + "1\n" + "2\n" + "3\n" + "4\n" + "@edges\n" + " label\n" + "0 1 0\n" + "0 2 0\n" + "0 3 0\n" + "0 4 0\n" + "1 2 0\n" + "1 3 0\n" + "2 3 0\n" + "2 4 0\n" + "3 4 0\n", + + "@nodes\n" + "label\n" + "0\n" + "1\n" + "2\n" + "3\n" + "4\n" + "5\n" + "@edges\n" + " label\n" + "0 3 0\n" + "0 4 0\n" + "0 5 0\n" + "1 3 0\n" + "1 4 0\n" + "1 5 0\n" + "2 3 0\n" + "2 4 0\n" + "2 5 0\n", + + "@nodes\n" + "label\n" + "0\n" + "1\n" + "2\n" + "3\n" + "4\n" + "5\n" + "@edges\n" + " label\n" + "0 3 0\n" + "0 4 0\n" + "0 5 0\n" + "1 3 0\n" + "1 4 0\n" + "1 5 0\n" + "2 3 0\n" + "2 5 0\n" +}; + + + +typedef SmartGraph Graph; +GRAPH_TYPEDEFS(Graph); + +typedef PlanarEmbedding PE; +typedef PlanarDrawing PD; +typedef PlanarColoring PC; + +void checkEmbedding(const Graph& graph, PE& pe) { + int face_num = 0; + + Graph::ArcMap face(graph, -1); + + for (ArcIt a(graph); a != INVALID; ++a) { + if (face[a] == -1) { + Arc b = a; + while (face[b] == -1) { + face[b] = face_num; + b = pe.next(graph.oppositeArc(b)); + } + check(face[b] == face_num, "Wrong face"); + ++face_num; + } + } + check(face_num + countNodes(graph) - countConnectedComponents(graph) == + countEdges(graph) + 1, "Euler test does not passed"); +} + +void checkKuratowski(const Graph& graph, PE& pe) { + std::map degs; + for (NodeIt n(graph); n != INVALID; ++n) { + int deg = 0; + for (IncEdgeIt e(graph, n); e != INVALID; ++e) { + if (pe.kuratowski(e)) { + ++deg; + } + } + ++degs[deg]; + } + for (std::map::iterator it = degs.begin(); it != degs.end(); ++it) { + check(it->first == 0 || it->first == 2 || + (it->first == 3 && it->second == 6) || + (it->first == 4 && it->second == 5), + "Wrong degree in Kuratowski graph"); + } + + // Not full test + check((degs[3] == 0) != (degs[4] == 0), "Wrong Kuratowski graph"); +} + +bool intersect(Point e1, Point e2, Point f1, Point f2) { + int l, r; + if (std::min(e1.x, e2.x) > std::max(f1.x, f2.x)) return false; + if (std::max(e1.x, e2.x) < std::min(f1.x, f2.x)) return false; + if (std::min(e1.y, e2.y) > std::max(f1.y, f2.y)) return false; + if (std::max(e1.y, e2.y) < std::min(f1.y, f2.y)) return false; + + l = (e2.x - e1.x) * (f1.y - e1.y) - (e2.y - e1.y) * (f1.x - e1.x); + r = (e2.x - e1.x) * (f2.y - e1.y) - (e2.y - e1.y) * (f2.x - e1.x); + if (!((l >= 0 && r <= 0) || (l <= 0 && r >= 0))) return false; + l = (f2.x - f1.x) * (e1.y - f1.y) - (f2.y - f1.y) * (e1.x - f1.x); + r = (f2.x - f1.x) * (e2.y - f1.y) - (f2.y - f1.y) * (e2.x - f1.x); + if (!((l >= 0 && r <= 0) || (l <= 0 && r >= 0))) return false; + return true; +} + +bool collinear(Point p, Point q, Point r) { + int v; + v = (q.x - p.x) * (r.y - p.y) - (q.y - p.y) * (r.x - p.x); + if (v != 0) return false; + v = (q.x - p.x) * (r.x - p.x) + (q.y - p.y) * (r.y - p.y); + if (v < 0) return false; + return true; +} + +void checkDrawing(const Graph& graph, PD& pd) { + for (Graph::NodeIt n(graph); n != INVALID; ++n) { + Graph::NodeIt m(n); + for (++m; m != INVALID; ++m) { + check(pd[m] != pd[n], "Two nodes with identical coordinates"); + } + } + + for (Graph::EdgeIt e(graph); e != INVALID; ++e) { + for (Graph::EdgeIt f(e); f != e; ++f) { + Point e1 = pd[graph.u(e)]; + Point e2 = pd[graph.v(e)]; + Point f1 = pd[graph.u(f)]; + Point f2 = pd[graph.v(f)]; + + if (graph.u(e) == graph.u(f)) { + check(!collinear(e1, e2, f2), "Wrong drawing"); + } else if (graph.u(e) == graph.v(f)) { + check(!collinear(e1, e2, f1), "Wrong drawing"); + } else if (graph.v(e) == graph.u(f)) { + check(!collinear(e2, e1, f2), "Wrong drawing"); + } else if (graph.v(e) == graph.v(f)) { + check(!collinear(e2, e1, f1), "Wrong drawing"); + } else { + check(!intersect(e1, e2, f1, f2), "Wrong drawing"); + } + } + } +} + +void checkColoring(const Graph& graph, PC& pc, int num) { + for (NodeIt n(graph); n != INVALID; ++n) { + check(pc.colorIndex(n) >= 0 && pc.colorIndex(n) < num, + "Wrong coloring"); + } + for (EdgeIt e(graph); e != INVALID; ++e) { + check(pc.colorIndex(graph.u(e)) != pc.colorIndex(graph.v(e)), + "Wrong coloring"); + } +} + +int main() { + + for (int i = 0; i < lgfn; ++i) { + std::istringstream lgfs(lgf[i]); + + SmartGraph graph; + graphReader(graph, lgfs).run(); + + check(simpleGraph(graph), "Test graphs must be simple"); + + PE pe(graph); + if (pe.run()) { + checkEmbedding(graph, pe); + + PlanarDrawing pd(graph); + pd.run(pe.embedding()); + checkDrawing(graph, pd); + + PlanarColoring pc(graph); + pc.runFiveColoring(pe.embedding()); + checkColoring(graph, pc, 5); + + } else { + checkKuratowski(graph, pe); + } + } + + return 0; +}