// Boost.Geometry (aka GGL, Generic Geometry Library) // Example: Affine Transformation (translate, scale, rotate) // // Copyright (c) 2009-2012 Mateusz Loskot, London, UK. // // Use, modification and distribution is subject to 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 <ctime> // for std::time #include <algorithm> #include <fstream> #include <iostream> #include <limits> #include <sstream> #include <boost/geometry/geometry.hpp> #include <boost/geometry/geometries/point_xy.hpp> #include <boost/geometry/geometries/polygon.hpp> #include <boost/geometry/algorithms/centroid.hpp> #include <boost/geometry/strategies/transform.hpp> #include <boost/geometry/strategies/transform/matrix_transformers.hpp> #include <boost/geometry/io/wkt/read.hpp> #if defined(HAVE_SVG) # include <boost/geometry/io/svg/write_svg.hpp> #endif #include <boost/random.hpp> #include <boost/range.hpp> #include <boost/shared_ptr.hpp> using namespace boost::geometry; struct random_style { random_style() : rng(static_cast<int>(std::time(0))), dist(0, 255), colour(rng, dist) {} std::string fill(double opacity = 1) { std::ostringstream oss; oss << "fill:rgba(" << colour() << "," << colour() << "," << colour() << "," << opacity << ");"; return oss.str(); } std::string stroke(int width, double opacity = 1) { std::ostringstream oss; oss << "stroke:rgba(" << colour() << "," << colour() << "," << colour() << "," << opacity << ");"; oss << "stroke-width:" << width << ";"; return oss.str(); } template <typename T> std::string text(T x, T y, std::string const& text) { std::ostringstream oss; oss << "<text x=\"" << static_cast<int>(x) - 90 << "\" y=\"" << static_cast<int>(y) << "\" font-family=\"Verdana\">" << text << "</text>"; return oss.str(); } boost::mt19937 rng; boost::uniform_int<> dist; boost::variate_generator<boost::mt19937&, boost::uniform_int<> > colour; }; template <typename OutputStream> struct svg_output { svg_output(OutputStream& os, double opacity = 1) : os(os), opacity(opacity) { os << "<?xml version=\"1.0\" standalone=\"no\"?>\n" << "<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\"\n" << "\"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\">\n" << "<svg width=\"100%\" height=\"100%\" version=\"1.1\"\n" << "xmlns=\"http://www.w3.org/2000/svg\">" << std::endl; } ~svg_output() { os << "</svg>" << std::endl; } template <typename G> void put(G const& g, std::string const& label) { std::string style_str(style.fill(opacity) + style.stroke(5, opacity)); #if defined(HAVE_SVG) os << boost::geometry::svg(g, style_str) << std::endl; #endif if (!label.empty()) { typename point_type<G>::type c; centroid(g, c); os << style.text(static_cast<int>(get<0>(c)), static_cast<int>(get<1>(c)), label); } } private: OutputStream& os; double opacity; random_style style; }; int main() { using namespace boost::geometry::strategy::transform; typedef boost::geometry::model::d2::point_xy<double> point_2d; try { std::string file("06_b_transformation_example.svg"); std::ofstream ofs(file.c_str()); svg_output<std::ofstream> svg(ofs, 0.5); // G1 - create subject for affine transformations model::polygon<point_2d> g1; read_wkt("POLYGON((50 250, 400 250, 150 50, 50 250))", g1); std::clog << "source box:\t" << boost::geometry::dsv(g1) << std::endl; svg.put(g1, "g1"); // G1 - Translate -> G2 translate_transformer<double, 2, 2> translate(0, 250); model::polygon<point_2d> g2; transform(g1, g2, translate); std::clog << "translated:\t" << boost::geometry::dsv(g2) << std::endl; svg.put(g2, "g2=g1.translate(0,250)"); // G2 - Scale -> G3 scale_transformer<double, 2, 2> scale(0.5, 0.5); model::polygon<point_2d> g3; transform(g2, g3, scale); std::clog << "scaled:\t" << boost::geometry::dsv(g3) << std::endl; svg.put(g3, "g3=g2.scale(0.5,0.5)"); // G3 - Combine rotate and translate -> G4 rotate_transformer<degree, double, 2, 2> rotate(45); // Compose matrix for the two transformation // Create transformer attached to the transformation matrix ublas_transformer<double, 2, 2> combined(boost::numeric::ublas::prod(rotate.matrix(), translate.matrix())); //combined(rotate.matrix()); // Apply transformation to subject geometry point-by-point model::polygon<point_2d> g4; transform(g3, g4, combined); std::clog << "rotated & translated:\t" << boost::geometry::dsv(g4) << std::endl; svg.put(g4, "g4 = g3.(rotate(45) * translate(0,250))"); std::clog << "Saved SVG file:\t" << file << std::endl; } catch (std::exception const& e) { std::cerr << e.what() << std::endl; } catch (...) { std::cerr << "unknown error" << std::endl; } return 0; }