当前位置: 首页>>代码示例>>C++>>正文


C++ Visitor::next_vertex方法代码示例

本文整理汇总了C++中Visitor::next_vertex方法的典型用法代码示例。如果您正苦于以下问题:C++ Visitor::next_vertex方法的具体用法?C++ Visitor::next_vertex怎么用?C++ Visitor::next_vertex使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在Visitor的用法示例。


在下文中一共展示了Visitor::next_vertex方法的1个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C++代码示例。

示例1: planar_face_traversal


//.........这里部分代码省略.........
    embedding_iterator_t pi, pi_begin, pi_end;

    visitor.begin_traversal();

    // Initialize the next_edge property map. This map is initialized from the
    // PlanarEmbedding so that get(next_edge, e)[v] is the edge that comes
    // after e in the clockwise embedding around vertex v.

    for(boost::tie(vi,vi_end) = vertices(g); vi != vi_end; ++vi)
      {
        vertex_t v(*vi);
        pi_begin = embedding[v].begin();
        pi_end = embedding[v].end();
        for(pi = pi_begin; pi != pi_end; ++pi)
          {
            edge_t e(*pi);
            std::map<vertex_t, edge_t> m = get(next_edge, e);
            m[v] = boost::next(pi) == pi_end ? *pi_begin : *boost::next(pi);
            put(next_edge, e, m);
          } 
      }

    // Take a copy of the edges in the graph here, since we want to accomodate
    // face traversals that add edges to the graph (for triangulation, in 
    // particular) and don't want to use invalidated edge iterators.
    // Also, while iterating over all edges in the graph, we single out
    // any self-loops, which need some special treatment in the face traversal.

    std::vector<edge_t> self_loops;
    std::vector<edge_t> edges_cache;
    std::vector<vertex_t> vertices_in_edge;

    for(boost::tie(fi,fi_end) = edges(g); fi != fi_end; ++fi)
      {
        edge_t e(*fi);
        edges_cache.push_back(e);
        if (source(e,g) == target(e,g))
          self_loops.push_back(e);
      }


    // Iterate over all edges in the graph
    ei_end = edges_cache.end();
    for(ei = edges_cache.begin(); ei != ei_end; ++ei)
      {

        edge_t e(*ei);
        vertices_in_edge.clear();
        vertices_in_edge.push_back(source(e,g));
        vertices_in_edge.push_back(target(e,g));

        typename std::vector<vertex_t>::iterator vi, vi_end;
        vi_end = vertices_in_edge.end();
        
        //Iterate over both vertices in the current edge
        for(vi = vertices_in_edge.begin(); vi != vi_end; ++vi)
          {

            vertex_t v(*vi);
            std::set<vertex_t> e_visited = get(visited, e);
            typename std::set<vertex_t>::iterator e_visited_found 
              = e_visited.find(v);
            
            if (e_visited_found == e_visited.end())
              visitor.begin_face();
            
            while (e_visited.find(v) == e_visited.end())
              {
                visitor.next_vertex(v);
                visitor.next_edge(e);
                e_visited.insert(v);
                put(visited, e, e_visited);
                v = source(e,g) == v ? target(e,g) : source(e,g);
                e = get(next_edge, e)[v];
                e_visited = get(visited, e);
              }
            
            if (e_visited_found == e_visited.end())
              visitor.end_face();
            
          }

      }

    // Iterate over all self-loops, visiting them once separately
    // (they've already been visited once, this visitation is for
    // the "inside" of the self-loop)
    
    ei_end = self_loops.end();
    for(ei = self_loops.begin(); ei != ei_end; ++ei)
      {
        visitor.begin_face();
        visitor.next_edge(*ei);
        visitor.next_vertex(source(*ei,g));
        visitor.end_face();
      }

    visitor.end_traversal();

  }
开发者ID:8573,项目名称:anura,代码行数:101,代码来源:planar_face_traversal.hpp


注:本文中的Visitor::next_vertex方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。