CQuadTree::Update()

QuadTreeUpdate.cpp

void CQuadTree::Update()
{
  // Iterate over every object in the tree.
  // This is why we stored them locally in Insert()
  for(size_t i = 0; i < mp_allBodies.size(); ++i)
  {
    // Object has moved.
    if(mp_allBodies[i]->needs_update)
    {
      // Remove the reference to the object from its current node.
      // Many thanks to @LorenSchmidt for the catch.
      for(auto i  = mp_allBodies[i]->pNode->nodeObjects.begin();
               i != mp_allBodies[i]->pNode->nodeObjects.end();
          /* no third part */)
      {
        if(*i == mp_allBodies[i])
        {
          i = mp_allBodies[i]->pNode->nodeObjects.erase(i);
          // If you can guarantee that you wont Insert() the same object
          // multiple times, you can "break;" out of the loop here.
        }
        
        else
        {
          ++i;
        }
      }

      // RInsert() will keep trying to find a node by moving up the tree
      // until it hits the root node. It will return false if it doesn't
      // fit into the root, either, so that means the object has been moved
      // off-screen, or off-tree.
      this->RInsert(mp_allBodies[i], mp_allBodies[i]->pNode->mp_Parent);
    }
  }
}