simgear/scene/util/SplicingVisitor.cxx

   1 #include "SplicingVisitor.hxx"
   2
   3 namespace simgear
   4 {
   5 using namespace osg;
   6
   7 SplicingVisitor::SplicingVisitor()
   8     : NodeVisitor(NodeVisitor::TRAVERSE_ALL_CHILDREN)
   9 {
  10     _childStack.push_back(NodeList());
  11 }
  12
  13 void SplicingVisitor::reset()
  14 {
  15     _childStack.clear();
  16     NodeVisitor::reset();
  17 }
  18
  19 NodeList SplicingVisitor::traverse(osg::Node& node)
  20 {
  21     NodeList result;
  22     _childStack.push_back(NodeList());
  23     NodeVisitor::traverse(node);
  24     result = _childStack.back();
  25     _childStack.pop_back();
  26     return result;
  27 }
  28 void SplicingVisitor::apply(osg::Node& node)
  29 {
  30     NodeVisitor::traverse(node);
  31     pushNode(&node);
  32 }
  33
  34 void SplicingVisitor::apply(osg::Group& node)
  35 {
  36     if (pushNode(getNewNode(node)))
  37         return;
  38     pushResultNode(&node, &node, traverse(node));
  39 }
  40
  41 osg::Group* SplicingVisitor::pushResultNode( osg::Group* node,
  42                                              osg::Group* newNode,
  43                                              const osg::NodeList& children )
  44 {
  45     ref_ptr<Group> result;
  46     if (node == newNode) {
  47         result = copyIfNeeded(*node, children);
  48     } else {
  49         result = newNode;
  50         for (NodeList::const_iterator itr = children.begin(), end = children.end();
  51              itr != end;
  52              ++itr)
  53             result->addChild(itr->get());
  54     }
  55     _childStack.back().push_back(result);
  56     recordNewNode(node, result.get());
  57     return result.get();
  58 }
  59
  60 osg::Node* SplicingVisitor::pushResultNode(osg::Node* node, osg::Node* newNode)
  61 {
  62     _childStack.back().push_back(newNode);
  63     recordNewNode(node, newNode);
  64     return newNode;
  65 }
  66
  67 osg::Node* SplicingVisitor::pushNode(osg::Node* node)
  68 {
  69     if (node)
  70         _childStack.back().push_back(node);
  71     return node;
  72 }
  73
  74 osg::Node* SplicingVisitor::getResult()
  75 {
  76     NodeList& top = _childStack.at(0);
  77     if (top.empty()) {
  78         return 0;
  79     } else if (top.size() == 1) {
  80         return top[0].get();
  81     } else {
  82         Group* result = new Group;
  83         for (NodeList::iterator itr = top.begin(), end = top.end();
  84              itr != end;
  85              ++itr)
  86             result->addChild(itr->get());
  87         return result;
  88     }
  89 }
  90
  91 osg::Node* SplicingVisitor::getNewNode(osg::Node* node)
  92 {
  93     ref_ptr<Node> tmpPtr(node);
  94     NodeMap::iterator itr;
  95     try {
  96         itr = _visited.find(tmpPtr);
  97     }
  98     catch (...) {
  99         tmpPtr.release();
 100         throw;
 101     }
 102     if (itr == _visited.end())
 103         return 0;
 104     else
 105         return itr->second.get();
 106 }
 107
 108 bool SplicingVisitor::recordNewNode(osg::Node* oldNode, osg::Node* newNode)
 109 {
 110     ref_ptr<Node> oldTmp(oldNode);
 111     ref_ptr<Node> newTmp(newNode);
 112     return _visited.insert(std::make_pair(oldTmp, newTmp)).second;
 113 }
 114 }