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<h1>boost/geometry/algorithms/overlay/traverse.hpp</h1><a href="traverse_8hpp.html">Go to the documentation of this file.</a><div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">// Boost.Geometry (aka GGL, Generic Geometry Library)</span>
<a name="l00002"></a>00002 <span class="comment">//</span>
<a name="l00003"></a>00003 <span class="comment">// Copyright Barend Gehrels 2007-2009, Geodan, Amsterdam, the Netherlands.</span>
<a name="l00004"></a>00004 <span class="comment">// Copyright Bruno Lalande 2008, 2009</span>
<a name="l00005"></a>00005 <span class="comment">// Use, modification and distribution is subject to the Boost Software License,</span>
<a name="l00006"></a>00006 <span class="comment">// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at</span>
<a name="l00007"></a>00007 <span class="comment">// http://www.boost.org/LICENSE_1_0.txt)</span>
<a name="l00008"></a>00008
<a name="l00009"></a>00009 <span class="preprocessor">#ifndef BOOST_GEOMETRY_ALGORITHMS_OVERLAY_TRAVERSE_HPP</span>
<a name="l00010"></a>00010 <span class="preprocessor"></span><span class="preprocessor">#define BOOST_GEOMETRY_ALGORITHMS_OVERLAY_TRAVERSE_HPP</span>
<a name="l00011"></a>00011 <span class="preprocessor"></span>
<a name="l00012"></a>00012 <span class="preprocessor">#include &lt;boost/range/functions.hpp&gt;</span>
<a name="l00013"></a>00013 <span class="preprocessor">#include &lt;boost/range/metafunctions.hpp&gt;</span>
<a name="l00014"></a>00014
<a name="l00015"></a>00015 <span class="preprocessor">#include &lt;<a class="code" href="access_8hpp.html">boost/geometry/core/access.hpp</a>&gt;</span>
<a name="l00016"></a>00016 <span class="preprocessor">#include &lt;<a class="code" href="coordinate__dimension_8hpp.html">boost/geometry/core/coordinate_dimension.hpp</a>&gt;</span>
<a name="l00017"></a>00017
<a name="l00018"></a>00018 <span class="preprocessor">#include &lt;<a class="code" href="copy__segments_8hpp.html">boost/geometry/algorithms/overlay/copy_segments.hpp</a>&gt;</span>
<a name="l00019"></a>00019 <span class="preprocessor">#include &lt;<a class="code" href="copy__segment__point_8hpp.html">boost/geometry/algorithms/overlay/copy_segment_point.hpp</a>&gt;</span>
<a name="l00020"></a>00020
<a name="l00021"></a>00021 <span class="preprocessor">#include &lt;<a class="code" href="geometries_2concepts_2check_8hpp.html">boost/geometry/geometries/concepts/check.hpp</a>&gt;</span>
<a name="l00022"></a>00022
<a name="l00023"></a>00023 <span class="preprocessor">#ifdef BOOST_GEOMETRY_DEBUG_INTERSECTION</span>
<a name="l00024"></a>00024 <span class="preprocessor"></span><span class="preprocessor">#include &lt;boost/geometry/extensions/gis/io/wkt/write_wkt.hpp&gt;</span>
<a name="l00025"></a>00025 <span class="preprocessor">#endif</span>
<a name="l00026"></a>00026 <span class="preprocessor"></span>
<a name="l00027"></a>00027
<a name="l00028"></a>00028 <span class="preprocessor">#include &lt;boost/geometry/algorithms/detail/overlay/turn_info.hpp&gt;</span>
<a name="l00029"></a>00029
<a name="l00030"></a>00030
<a name="l00031"></a>00031
<a name="l00032"></a>00032
<a name="l00033"></a>00033 <span class="keyword">namespace </span>boost { <span class="keyword">namespace </span>geometry
<a name="l00034"></a>00034 {
<a name="l00035"></a>00035
<a name="l00036"></a>00036
<a name="l00037"></a>00037 <span class="preprocessor">#ifndef DOXYGEN_NO_DETAIL</span>
<a name="l00038"></a>00038 <span class="preprocessor"></span><span class="keyword">namespace </span>detail { <span class="keyword">namespace </span>overlay {
<a name="l00039"></a>00039
<a name="l00040"></a>00040
<a name="l00041"></a>00041 <span class="keyword">template</span> &lt;<span class="keyword">typename</span> Info, <span class="keyword">typename</span> Turn&gt;
<a name="l00042"></a>00042 <span class="keyword">inline</span> <span class="keywordtype">void</span> set_visited_for_contine(Info&amp; info, Turn <span class="keyword">const</span>&amp; turn)
<a name="l00043"></a>00043 {
<a name="l00044"></a>00044 <span class="comment">// On "continue", set "visited" for ALL directions</span>
<a name="l00045"></a>00045
<a name="l00046"></a>00046 <span class="keywordflow">if</span> (turn.operation == detail::overlay::operation_continue)
<a name="l00047"></a>00047 {
<a name="l00048"></a>00048 <span class="keywordflow">for</span> (<span class="keyword">typename</span> boost::range_iterator
<a name="l00049"></a>00049 &lt;
<a name="l00050"></a>00050 <span class="keyword">typename</span> Info::traversal_vector
<a name="l00051"></a>00051 &gt;::type it = boost::begin(info.turns);
<a name="l00052"></a>00052 it != boost::end(info.turns);
<a name="l00053"></a>00053 ++it)
<a name="l00054"></a>00054 {
<a name="l00055"></a>00055 <span class="keywordflow">if</span> (it-&gt;visited.none())
<a name="l00056"></a>00056 {
<a name="l00057"></a>00057 it-&gt;visited.set_visited();
<a name="l00058"></a>00058 }
<a name="l00059"></a>00059 }
<a name="l00060"></a>00060 }
<a name="l00061"></a>00061 }
<a name="l00062"></a>00062
<a name="l00063"></a>00063
<a name="l00064"></a>00064 <span class="keyword">template</span>
<a name="l00065"></a>00065 &lt;
<a name="l00066"></a>00066 <span class="keyword">typename</span> GeometryOut,
<a name="l00067"></a>00067 <span class="keyword">typename</span> G1,
<a name="l00068"></a>00068 <span class="keyword">typename</span> G2,
<a name="l00069"></a>00069 <span class="keyword">typename</span> TurnPoints,
<a name="l00070"></a>00070 <span class="keyword">typename</span> IntersectionInfo
<a name="l00071"></a>00071 &gt;
<a name="l00072"></a>00072 <span class="keyword">inline</span> <span class="keywordtype">void</span> assign_next_ip(G1 <span class="keyword">const</span>&amp; g1, G2 <span class="keyword">const</span>&amp; g2, operation_type operation,
<a name="l00073"></a>00073 TurnPoints&amp; turn_points,
<a name="l00074"></a>00074 <span class="keyword">typename</span> boost::range_iterator&lt;TurnPoints&gt;::type &amp; ip,
<a name="l00075"></a>00075 GeometryOut&amp; current_output,
<a name="l00076"></a>00076 IntersectionInfo &amp; info,
<a name="l00077"></a>00077 segment_identifier&amp; seg_id)
<a name="l00078"></a>00078 {
<a name="l00079"></a>00079 <span class="preprocessor">#ifdef BOOST_GEOMETRY_DEBUG_INTERSECTION</span>
<a name="l00080"></a>00080 <span class="preprocessor"></span> <span class="comment">//std::cout &lt;&lt; "traverse: take: " &lt;&lt; info &lt;&lt; std::endl;</span>
<a name="l00081"></a>00081 <span class="preprocessor">#endif</span>
<a name="l00082"></a>00082 <span class="preprocessor"></span> info.visited.set_visited();
<a name="l00083"></a>00083 set_visited_for_contine(*ip, info);
<a name="l00084"></a>00084
<a name="l00085"></a>00085 <span class="comment">// If there is no next IP on this segment</span>
<a name="l00086"></a>00086 <span class="keywordflow">if</span> (info.enriched.next_ip_index &lt; 0)
<a name="l00087"></a>00087 {
<a name="l00088"></a>00088 <span class="keywordflow">if</span> (info.seg_id.source_index == 0)
<a name="l00089"></a>00089 {
<a name="l00090"></a>00090 <a class="code" href="group__overlay.html#g81ff9e1c0534d39cec7b48b1cd3edb4e" title="Traverses through intersection points / geometries.">geometry::copy_segments</a>(g1, info.seg_id,
<a name="l00091"></a>00091 info.enriched.travels_to_vertex_index,
<a name="l00092"></a>00092 current_output);
<a name="l00093"></a>00093 }
<a name="l00094"></a>00094 <span class="keywordflow">else</span>
<a name="l00095"></a>00095 {
<a name="l00096"></a>00096 <a class="code" href="group__overlay.html#g81ff9e1c0534d39cec7b48b1cd3edb4e" title="Traverses through intersection points / geometries.">geometry::copy_segments</a>(g2, info.seg_id,
<a name="l00097"></a>00097 info.enriched.travels_to_vertex_index,
<a name="l00098"></a>00098 current_output);
<a name="l00099"></a>00099 }
<a name="l00100"></a>00100 ip = boost::begin(turn_points) + info.enriched.travels_to_ip_index;
<a name="l00101"></a>00101 seg_id = info.seg_id;
<a name="l00102"></a>00102 }
<a name="l00103"></a>00103 <span class="keywordflow">else</span>
<a name="l00104"></a>00104 {
<a name="l00105"></a>00105 ip = boost::begin(turn_points) + info.enriched.next_ip_index;
<a name="l00106"></a>00106 seg_id = info.seg_id;
<a name="l00107"></a>00107 }
<a name="l00108"></a>00108 *(std::back_inserter(current_output)++) = ip-&gt;point;
<a name="l00109"></a>00109 }
<a name="l00110"></a>00110
<a name="l00111"></a>00111
<a name="l00112"></a>00112 <span class="keyword">inline</span> <span class="keywordtype">bool</span> select_source(operation_type operation, <span class="keywordtype">int</span> source1, <span class="keywordtype">int</span> source2)
<a name="l00113"></a>00113 {
<a name="l00114"></a>00114 <span class="keywordflow">return</span>
<a name="l00115"></a>00115 (operation == operation_intersection &amp;&amp; source1 != source2)
<a name="l00116"></a>00116 || (operation == operation_union &amp;&amp; source1 == source2);
<a name="l00117"></a>00117 }
<a name="l00118"></a>00118
<a name="l00119"></a>00119
<a name="l00120"></a>00120 <span class="keyword">template</span>
<a name="l00121"></a>00121 &lt;
<a name="l00122"></a>00122 <span class="keyword">typename</span> Turn,
<a name="l00123"></a>00123 <span class="keyword">typename</span> Iterator
<a name="l00124"></a>00124 &gt;
<a name="l00125"></a>00125 <span class="keyword">inline</span> <span class="keywordtype">bool</span> select_next_ip(operation_type operation,
<a name="l00126"></a>00126 Turn&amp; turn,
<a name="l00127"></a>00127 segment_identifier <span class="keyword">const</span>&amp; seg_id,
<a name="l00128"></a>00128 Iterator&amp; <a class="code" href="group__selected.html#gfa35b0560d5c1296cc974b3f477a9f5c" title="Checks if one geometry is selected by a point lying within or in the neighborhood...">selected</a>)
<a name="l00129"></a>00129 {
<a name="l00130"></a>00130 <span class="keywordtype">bool</span> has_tp = <span class="keyword">false</span>;
<a name="l00131"></a>00131 selected = boost::end(turn.turns);
<a name="l00132"></a>00132 <span class="keywordflow">for</span> (Iterator it = boost::begin(turn.turns);
<a name="l00133"></a>00133 it != boost::end(turn.turns);
<a name="l00134"></a>00134 ++it)
<a name="l00135"></a>00135 {
<a name="l00136"></a>00136 <span class="comment">// In some cases there are two alternatives.</span>
<a name="l00137"></a>00137 <span class="comment">// For "ii", take the other one (alternate)</span>
<a name="l00138"></a>00138 <span class="comment">// For "uu", take the same one</span>
<a name="l00139"></a>00139 <span class="comment">// For "cc", take either one, but if there is a starting one,</span>
<a name="l00140"></a>00140 <span class="comment">// take that one.</span>
<a name="l00141"></a>00141 <span class="keywordflow">if</span> ( (it-&gt;operation == operation_continue
<a name="l00142"></a>00142 &amp;&amp; (! has_tp
<a name="l00143"></a>00143 || it-&gt;visited.started()
<a name="l00144"></a>00144 )
<a name="l00145"></a>00145 )
<a name="l00146"></a>00146 || (it-&gt;operation == operation
<a name="l00147"></a>00147 &amp;&amp; (! has_tp
<a name="l00148"></a>00148 || select_source(operation,
<a name="l00149"></a>00149 it-&gt;seg_id.source_index, seg_id.source_index)
<a name="l00150"></a>00150 )
<a name="l00151"></a>00151 )
<a name="l00152"></a>00152 )
<a name="l00153"></a>00153 {
<a name="l00154"></a>00154 selected = it;
<a name="l00155"></a>00155 has_tp = <span class="keyword">true</span>;
<a name="l00156"></a>00156 }
<a name="l00157"></a>00157 }
<a name="l00158"></a>00158
<a name="l00159"></a>00159 <span class="keywordflow">return</span> has_tp;
<a name="l00160"></a>00160 }
<a name="l00161"></a>00161
<a name="l00162"></a>00162
<a name="l00163"></a>00163 <span class="keyword">template</span> &lt;<span class="keyword">typename</span> Container&gt;
<a name="l00164"></a>00164 <span class="keyword">inline</span> <span class="keywordtype">void</span> stop_gracefully(Container&amp; container, <span class="keywordtype">bool</span>&amp; stop,
<a name="l00165"></a>00165 std::string <span class="keyword">const</span>&amp; reason)
<a name="l00166"></a>00166 {
<a name="l00167"></a>00167 <span class="preprocessor">#ifdef BOOST_GEOMETRY_DEBUG_INTERSECTION</span>
<a name="l00168"></a>00168 <span class="preprocessor"></span> std::cout &lt;&lt; <span class="stringliteral">"STOPPING: "</span> &lt;&lt; reason &lt;&lt; std::endl;
<a name="l00169"></a>00169 <span class="preprocessor">#endif</span>
<a name="l00170"></a>00170 <span class="preprocessor"></span>
<a name="l00171"></a>00171 stop = <span class="keyword">true</span>;
<a name="l00172"></a>00172 <span class="keywordflow">if</span> (container.size() &gt; 0)
<a name="l00173"></a>00173 {
<a name="l00174"></a>00174 <span class="comment">// Two-step adding first value, without assignment</span>
<a name="l00175"></a>00175 <span class="comment">// and without (erroneous) push_back of reference</span>
<a name="l00176"></a>00176 <span class="keyword">typename</span> boost::range_value&lt;Container&gt;::type p;
<a name="l00177"></a>00177 <a class="code" href="namespaceboost_1_1geometry.html#ff15abe2a4412c1913d5c4d5875f45f7" title="Copies coordinates from source to destination point.">geometry::copy_coordinates</a>(container.front(), p);
<a name="l00178"></a>00178 *(std::back_inserter(container)++) = p;
<a name="l00179"></a>00179
<a name="l00180"></a>00180 }
<a name="l00181"></a>00181 }
<a name="l00182"></a>00182
<a name="l00183"></a>00183 }} <span class="comment">// namespace detail::overlay</span>
<a name="l00184"></a>00184 <span class="preprocessor">#endif // DOXYGEN_NO_DETAIL</span>
<a name="l00185"></a>00185 <span class="preprocessor"></span>
<a name="l00186"></a>00186
<a name="l00191"></a>00191 <span class="keyword">template</span>
<a name="l00192"></a>00192 &lt;
<a name="l00193"></a>00193 <span class="keyword">typename</span> SideStrategy,
<a name="l00194"></a>00194 <span class="keyword">typename</span> GeometryOut,
<a name="l00195"></a>00195 <span class="keyword">typename</span> Geometry1,
<a name="l00196"></a>00196 <span class="keyword">typename</span> Geometry2,
<a name="l00197"></a>00197 <span class="keyword">typename</span> TurnPoints,
<a name="l00198"></a>00198 <span class="keyword">typename</span> OutputIterator
<a name="l00199"></a>00199 &gt;
<a name="l00200"></a><a class="code" href="group__overlay.html#gb2ade7d6588919520fb9848b2ffe8886">00200</a> <span class="keyword">inline</span> <span class="keywordtype">void</span> <a class="code" href="group__overlay.html#gb2ade7d6588919520fb9848b2ffe8886" title="Traverses through intersection points / geometries.">traverse</a>(Geometry1 <span class="keyword">const</span>&amp; geometry1,
<a name="l00201"></a>00201 Geometry2 <span class="keyword">const</span>&amp; geometry2,
<a name="l00202"></a>00202 detail::overlay::operation_type operation,
<a name="l00203"></a>00203 TurnPoints&amp; turn_points,
<a name="l00204"></a>00204 OutputIterator out)
<a name="l00205"></a>00205 {
<a name="l00206"></a>00206 concept::check&lt;const Geometry1&gt;();
<a name="l00207"></a>00207 concept::check&lt;const Geometry2&gt;();
<a name="l00208"></a>00208
<a name="l00209"></a>00209 <span class="keyword">typedef</span> <span class="keyword">typename</span> boost::range_iterator&lt;TurnPoints&gt;::type turn_iterator;
<a name="l00210"></a>00210 <span class="keyword">typedef</span> <span class="keyword">typename</span> boost::range_value&lt;TurnPoints&gt;::type turn_type;
<a name="l00211"></a>00211 <span class="keyword">typedef</span> <span class="keyword">typename</span> boost::range_iterator
<a name="l00212"></a>00212 &lt;
<a name="l00213"></a>00213 <span class="keyword">typename</span> turn_type::traversal_vector
<a name="l00214"></a>00214 &gt;::type turn_operation_iterator_type;
<a name="l00215"></a>00215
<a name="l00216"></a>00216
<a name="l00217"></a>00217 <span class="comment">// Iterate through all unvisited points</span>
<a name="l00218"></a>00218 <span class="keywordflow">for</span> (turn_iterator it = boost::begin(turn_points);
<a name="l00219"></a>00219 it != boost::end(turn_points);
<a name="l00220"></a>00220 ++it)
<a name="l00221"></a>00221 {
<a name="l00222"></a>00222 <span class="preprocessor">#ifdef BOOST_GEOMETRY_DEBUG_INTERSECTION</span>
<a name="l00223"></a>00223 <span class="preprocessor"></span> <span class="comment">//std::cout &lt;&lt; "traversal: try: " &lt;&lt; *it;</span>
<a name="l00224"></a>00224 <span class="preprocessor">#endif</span>
<a name="l00225"></a>00225 <span class="preprocessor"></span>
<a name="l00226"></a>00226 <span class="keywordflow">for</span> (turn_operation_iterator_type iit = boost::begin(it-&gt;turns);
<a name="l00227"></a>00227 iit != boost::end(it-&gt;turns);
<a name="l00228"></a>00228 ++iit)
<a name="l00229"></a>00229 {
<a name="l00230"></a>00230 <span class="keywordflow">if</span> (iit-&gt;visited.none()
<a name="l00231"></a>00231 &amp;&amp; (iit-&gt;operation == operation
<a name="l00232"></a>00232 || iit-&gt;operation == detail::overlay::operation_continue)
<a name="l00233"></a>00233 )
<a name="l00234"></a>00234 {
<a name="l00235"></a>00235 iit-&gt;visited.set_started();
<a name="l00236"></a>00236 set_visited_for_contine(*it, *iit);
<a name="l00237"></a>00237
<a name="l00238"></a>00238 GeometryOut current_output;
<a name="l00239"></a>00239 *(std::back_inserter(current_output)++) = it-&gt;point;
<a name="l00240"></a>00240
<a name="l00241"></a>00241 turn_iterator current = it;
<a name="l00242"></a>00242 turn_operation_iterator_type current_iit = iit;
<a name="l00243"></a>00243 <a class="code" href="structboost_1_1geometry_1_1segment__identifier.html">segment_identifier</a> current_seg_id;
<a name="l00244"></a>00244
<a name="l00245"></a>00245 #ifdef BOOST_GEOMETRY_DEBUG_INTERSECTION
<a name="l00246"></a>00246 <span class="comment">//std::cout &lt;&lt; "traversal: start: " &lt;&lt; *current;</span>
<a name="l00247"></a>00247 #endif
<a name="l00248"></a>00248
<a name="l00249"></a>00249 detail::overlay::assign_next_ip(geometry1, geometry2,
<a name="l00250"></a>00250 operation,
<a name="l00251"></a>00251 turn_points,
<a name="l00252"></a>00252 current, current_output,
<a name="l00253"></a>00253 *iit, current_seg_id);
<a name="l00254"></a>00254 detail::overlay::select_next_ip(
<a name="l00255"></a>00255 operation,
<a name="l00256"></a>00256 *current,
<a name="l00257"></a>00257 current_seg_id, current_iit);
<a name="l00258"></a>00258
<a name="l00259"></a>00259 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> i = 0;
<a name="l00260"></a>00260 <span class="keywordtype">bool</span> stop = <span class="keyword">false</span>;
<a name="l00261"></a>00261
<a name="l00262"></a>00262 <span class="keywordflow">while</span> (current_iit != iit &amp;&amp; ! stop)
<a name="l00263"></a>00263 {
<a name="l00264"></a>00264
<a name="l00265"></a>00265 <span class="preprocessor">#ifdef BOOST_GEOMETRY_DEBUG_INTERSECTION</span>
<a name="l00266"></a>00266 <span class="preprocessor"></span> <span class="comment">//std::cout &lt;&lt; "traverse: " &lt;&lt; *current;</span>
<a name="l00267"></a>00267 <span class="preprocessor">#endif</span>
<a name="l00268"></a>00268 <span class="preprocessor"></span>
<a name="l00269"></a>00269 <span class="comment">// We assume clockwise polygons only, non self-intersecting, closed.</span>
<a name="l00270"></a>00270 <span class="comment">// However, the input might be different, and checking validity</span>
<a name="l00271"></a>00271 <span class="comment">// is up to the library user.</span>
<a name="l00272"></a>00272
<a name="l00273"></a>00273 <span class="comment">// Therefore we make here some sanity checks. If the input</span>
<a name="l00274"></a>00274 <span class="comment">// violates the assumptions, the output polygon will not be correct</span>
<a name="l00275"></a>00275 <span class="comment">// but the routine will stop and output the current polygon, and</span>
<a name="l00276"></a>00276 <span class="comment">// will continue with the next one.</span>
<a name="l00277"></a>00277
<a name="l00278"></a>00278 <span class="comment">// Below three reasons to stop.</span>
<a name="l00279"></a>00279 assign_next_ip(geometry1, geometry2,
<a name="l00280"></a>00280 operation,
<a name="l00281"></a>00281 turn_points, current, current_output,
<a name="l00282"></a>00282 *current_iit, current_seg_id);
<a name="l00283"></a>00283
<a name="l00284"></a>00284 <span class="keywordflow">if</span> (! detail::overlay::select_next_ip(
<a name="l00285"></a>00285 operation,
<a name="l00286"></a>00286 *current,
<a name="l00287"></a>00287 current_seg_id, current_iit))
<a name="l00288"></a>00288 {
<a name="l00289"></a>00289 <span class="comment">// Should not occur in valid (non-self-intersecting) polygons</span>
<a name="l00290"></a>00290 <span class="comment">// Should not occur in self-intersecting polygons without spikes</span>
<a name="l00291"></a>00291 <span class="comment">// Might occur in polygons with spikes</span>
<a name="l00292"></a>00292 detail::overlay::stop_gracefully(
<a name="l00293"></a>00293 current_output, stop, <span class="stringliteral">"Dead end"</span>);
<a name="l00294"></a>00294 }
<a name="l00295"></a>00295
<a name="l00296"></a>00296
<a name="l00297"></a>00297
<a name="l00298"></a>00298 <span class="keywordflow">if</span> (current_iit-&gt;visited.visited())
<a name="l00299"></a>00299 {
<a name="l00300"></a>00300 <span class="comment">// It visits a visited node again, without passing the start node.</span>
<a name="l00301"></a>00301 <span class="comment">// This makes it suspicious for endless loops</span>
<a name="l00302"></a>00302 <span class="comment">// Check if it is really same node</span>
<a name="l00303"></a>00303 detail::overlay::stop_gracefully(
<a name="l00304"></a>00304 current_output, stop, <span class="stringliteral">"Visit again"</span>);
<a name="l00305"></a>00305 }
<a name="l00306"></a>00306
<a name="l00307"></a>00307
<a name="l00308"></a>00308 <span class="keywordflow">if</span> (i++ &gt; turn_points.size())
<a name="l00309"></a>00309 {
<a name="l00310"></a>00310 <span class="comment">// Sanity check: there may be never more loops</span>
<a name="l00311"></a>00311 <span class="comment">// than intersection points.</span>
<a name="l00312"></a>00312 detail::overlay::stop_gracefully(
<a name="l00313"></a>00313 current_output, stop, <span class="stringliteral">"Endless loop"</span>);
<a name="l00314"></a>00314 }
<a name="l00315"></a>00315 }
<a name="l00316"></a>00316
<a name="l00317"></a>00317 iit-&gt;visited.set_finished();
<a name="l00318"></a>00318
<a name="l00319"></a>00319 <span class="preprocessor">#ifdef BOOST_GEOMETRY_DEBUG_INTERSECTION</span>
<a name="l00320"></a>00320 <span class="preprocessor"></span> <span class="comment">//std::cout &lt;&lt; "traversal: finish: " &lt;&lt; *current;</span>
<a name="l00321"></a>00321 std::cout &lt;&lt; geometry::wkt(current_output) &lt;&lt; std::endl;
<a name="l00322"></a>00322 <span class="preprocessor">#endif</span>
<a name="l00323"></a>00323 <span class="preprocessor"></span>
<a name="l00324"></a>00324 *out++ = current_output;
<a name="l00325"></a>00325 }
<a name="l00326"></a>00326 }
<a name="l00327"></a>00327 }
<a name="l00328"></a>00328 <span class="preprocessor">#ifdef BOOST_GEOMETRY_DEBUG_INTERSECTION</span>
<a name="l00329"></a>00329 <span class="preprocessor"></span> std::cout &lt;&lt; <span class="stringliteral">"traversal: all IP's handled"</span> &lt;&lt; std::endl;
<a name="l00330"></a>00330 <span class="preprocessor">#endif</span>
<a name="l00331"></a>00331 <span class="preprocessor"></span>}
<a name="l00332"></a>00332
<a name="l00333"></a>00333
<a name="l00334"></a>00334 }} <span class="comment">// namespace boost::geometry</span>
<a name="l00335"></a>00335
<a name="l00336"></a>00336
<a name="l00337"></a>00337 <span class="preprocessor">#endif // BOOST_GEOMETRY_ALGORITHMS_OVERLAY_TRAVERSE_HPP</span>
</pre></div></div>
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<p>December 1, 2009</p>
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<small>Copyright <20> 1995-2009 Barend Gehrels, Geodan, Amsterdam<br>
Copyright <20> 2008-2009 Bruno Lalande, Paris<br>
Copyright <20> 2009 Mateusz Loskot, Cadcorp, London<br>
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