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