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boost-react-native-bundle

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Boost library as in https://sourceforge.net/projects/boost/files/boost/1.57.0/

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<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=windows-1252"> <title>Polygon Set Usage</title> </head> <body> <p><font face="Courier New">/*<br> Copyright 2008 Intel Corporation<br> <br> Use, modification and distribution are subject to the Boost Software License,<br> Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at<br> http://www.boost.org/LICENSE_1_0.txt).<br> */<br> #include &lt;boost/polygon/polygon.hpp&gt;<br> #include &lt;cassert&gt;<br> namespace gtl = boost::polygon;<br> using namespace boost::polygon::operators;<br><br> int main() {<br>&nbsp; &nbsp; //lets declare ourselves a polygon set<br>&nbsp; &nbsp; using namespace gtl; //because of operators<br>&nbsp; &nbsp; typedef std::vector&lt;polygon_data&lt;int&gt; &gt; PolygonSet;<br>&nbsp; &nbsp; PolygonSet ps;<br>&nbsp; &nbsp; <br>&nbsp; &nbsp; //lets put some data in<br>&nbsp; &nbsp; ps += rectangle_data&lt;int&gt;(0, 0, 10, 10);<br>&nbsp; &nbsp; <br>&nbsp; &nbsp; //now lets do something interesting<br>&nbsp; &nbsp; PolygonSet ps2;<br>&nbsp; &nbsp; ps2 += rectangle_data&lt;int&gt;(5, 5, 15, 15);<br>&nbsp; &nbsp; PolygonSet ps3;<br>&nbsp; &nbsp; assign(ps3, ps * ps2); //woah, I just felt the room flex around me<br>&nbsp; &nbsp; PolygonSet ps4;<br>&nbsp; &nbsp; ps4 += ps + ps2;<br>&nbsp; &nbsp; <br>&nbsp; &nbsp; //assert that area of result is equal to sum of areas<br>&nbsp; &nbsp; //of input geometry minus the area of overlap between inputs<br>&nbsp; &nbsp; assert(area(ps4) == area(ps) + area(ps2) - area(ps3));<br>&nbsp; &nbsp; <br>&nbsp; &nbsp; //I don't even see the code anymore, all<br>&nbsp; &nbsp; //I see is bounding box...interval...triangle<br>&nbsp; &nbsp; <br>&nbsp; &nbsp; //lets try that again in slow motion shall we?<br>&nbsp;&nbsp;&nbsp; assert(equivalence((ps + ps2) - (ps * ps2), ps ^ ps2));<br> <br> &nbsp;&nbsp;&nbsp; //hmm, subtracting the intersection from the union<br> &nbsp;&nbsp;&nbsp; //is equivalent to the xor, all this in one line of code,<br> &nbsp;&nbsp;&nbsp; //now we're programming in bullet time<br> &nbsp;&nbsp;&nbsp; //(by the way, xor is implemented as one pass, not composition)&nbsp; <br>&nbsp; &nbsp; <br>&nbsp; &nbsp; //just for fun<br>&nbsp; &nbsp; rectangle_data&lt;int&gt; rect;<br>&nbsp; &nbsp; assert(extents(rect, ps ^ ps2));<br>&nbsp; &nbsp; assert(area(rect) == 225);<br>&nbsp; &nbsp; assert(area(rect ^ (ps ^ ps2)) == area(rect) - area(ps ^ ps2)); <br>&nbsp; &nbsp; return 0;<br>}<br>&nbsp; &nbsp; <br>//Now you know how to use the polygon set concept with library polygons<br>&nbsp; &nbsp; &nbsp;</font></p> <table class="docinfo" rules="none" frame="void" id="table1"> <colgroup> <col class="docinfo-name"><col class="docinfo-content"> </colgroup> <tbody vAlign="top"> <tr> <th class="docinfo-name">Copyright:</th> <td>Copyright � Intel Corporation 2008-2010.</td> </tr> <tr class="field"> <th class="docinfo-name">License:</th> <td class="field-body">Distributed under the Boost Software License, Version 1.0. (See accompanying file <tt class="literal"> <span class="pre">LICENSE_1_0.txt</span></tt> or copy at <a class="reference" target="_top" href="http://www.boost.org/LICENSE_1_0.txt"> http://www.boost.org/LICENSE_1_0.txt</a>)</td> </tr> </table> </body> </html>