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//=======================================================================
// Copyright 2008 Aaron Windsor
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//=======================================================================
#include <boost/property_map/property_map.hpp>
#include <boost/core/lightweight_test.hpp>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/properties.hpp>
#include <boost/graph/graph_traits.hpp>
#include <boost/graph/is_straight_line_drawing.hpp>
#include <vector>
using namespace boost;
struct coord_t
{
std::size_t x;
std::size_t y;
};
int main(int, char*[])
{
typedef adjacency_list< vecS, vecS, undirectedS,
property< vertex_index_t, int > >
graph_t;
typedef std::vector< coord_t > drawing_storage_t;
typedef boost::iterator_property_map< drawing_storage_t::iterator,
property_map< graph_t, vertex_index_t >::type >
drawing_t;
graph_t g(4);
add_edge(0, 1, g);
add_edge(2, 3, g);
drawing_storage_t drawing_storage(num_vertices(g));
drawing_t drawing(drawing_storage.begin(), get(vertex_index, g));
// two perpendicular lines that intersect at (1,1)
drawing[0].x = 1;
drawing[0].y = 0;
drawing[1].x = 1;
drawing[1].y = 2;
drawing[2].x = 0;
drawing[2].y = 1;
drawing[3].x = 2;
drawing[3].y = 1;
BOOST_TEST(!is_straight_line_drawing(g, drawing));
// two parallel horizontal lines
drawing[0].x = 0;
drawing[0].y = 0;
drawing[1].x = 2;
drawing[1].y = 0;
BOOST_TEST(is_straight_line_drawing(g, drawing));
// two parallel vertical lines
drawing[0].x = 0;
drawing[0].y = 0;
drawing[1].x = 0;
drawing[1].y = 2;
drawing[2].x = 1;
drawing[2].y = 0;
drawing[3].x = 1;
drawing[3].y = 2;
BOOST_TEST(is_straight_line_drawing(g, drawing));
// two lines that intersect at (1,1)
drawing[0].x = 0;
drawing[0].y = 0;
drawing[1].x = 2;
drawing[1].y = 2;
drawing[2].x = 0;
drawing[2].y = 2;
drawing[3].x = 2;
drawing[3].y = 0;
BOOST_TEST(!is_straight_line_drawing(g, drawing));
// K_4 arranged in a diamond pattern, so that edges intersect
g = graph_t(4);
add_edge(0, 1, g);
add_edge(0, 2, g);
add_edge(0, 3, g);
add_edge(1, 2, g);
add_edge(1, 3, g);
add_edge(2, 3, g);
drawing_storage = drawing_storage_t(num_vertices(g));
drawing = drawing_t(drawing_storage.begin(), get(vertex_index, g));
drawing[0].x = 1;
drawing[0].y = 2;
drawing[1].x = 2;
drawing[1].y = 1;
drawing[2].x = 1;
drawing[2].y = 0;
drawing[3].x = 0;
drawing[3].y = 1;
BOOST_TEST(!is_straight_line_drawing(g, drawing));
// K_4 arranged so that no edges intersect
drawing[0].x = 0;
drawing[0].y = 0;
drawing[1].x = 1;
drawing[1].y = 1;
drawing[2].x = 1;
drawing[2].y = 2;
drawing[3].x = 2;
drawing[3].y = 0;
BOOST_TEST(is_straight_line_drawing(g, drawing));
// a slightly more complicated example - edges (0,1) and (4,5)
// intersect
g = graph_t(8);
add_edge(0, 1, g);
add_edge(2, 3, g);
add_edge(4, 5, g);
add_edge(6, 7, g);
drawing_storage = drawing_storage_t(num_vertices(g));
drawing = drawing_t(drawing_storage.begin(), get(vertex_index, g));
drawing[0].x = 1;
drawing[0].y = 1;
drawing[1].x = 5;
drawing[1].y = 4;
drawing[2].x = 2;
drawing[2].y = 5;
drawing[3].x = 4;
drawing[3].y = 4;
drawing[4].x = 3;
drawing[4].y = 4;
drawing[5].x = 3;
drawing[5].y = 2;
drawing[6].x = 4;
drawing[6].y = 2;
drawing[7].x = 1;
drawing[7].y = 1;
BOOST_TEST(!is_straight_line_drawing(g, drawing));
// form a graph consisting of a bunch of parallel vertical edges,
// then place an edge at various positions to intersect edges
g = graph_t(22);
for (int i = 0; i < 11; ++i)
add_edge(2 * i, 2 * i + 1, g);
drawing_storage = drawing_storage_t(num_vertices(g));
drawing = drawing_t(drawing_storage.begin(), get(vertex_index, g));
for (int i = 0; i < 10; ++i)
{
drawing[2 * i].x = i;
drawing[2 * i].y = 0;
drawing[2 * i + 1].x = i;
drawing[2 * i + 1].y = 10;
}
// put the final edge as a horizontal edge intersecting one other edge
drawing[20].x = 5;
drawing[20].y = 5;
drawing[21].x = 7;
drawing[21].y = 5;
BOOST_TEST(!is_straight_line_drawing(g, drawing));
// make the final edge a diagonal intersecting multiple edges
drawing[20].x = 2;
drawing[20].y = 4;
drawing[21].x = 9;
drawing[21].y = 7;
BOOST_TEST(!is_straight_line_drawing(g, drawing));
// reverse the slope
drawing[20].x = 2;
drawing[20].y = 7;
drawing[21].x = 9;
drawing[21].y = 4;
BOOST_TEST(!is_straight_line_drawing(g, drawing));
return boost::report_errors();
}
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