model.h

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/* Author: Wim Meeussen */

#ifndef URDF_INTERFACE_MODEL_H
#define URDF_INTERFACE_MODEL_H

#include <string>
#include <map>
#include <boost/function.hpp>
#include <urdf_interface/link.h>


namespace urdf {

class ModelInterface
{
public:
  boost::shared_ptr<const Link> getRoot(void) const{return this->root_link_;};
  boost::shared_ptr<const Link> getLink(const std::string& name) const
  {
    boost::shared_ptr<const Link> ptr;
    if (this->links_.find(name) == this->links_.end())
      ptr.reset();
    else
      ptr = this->links_.find(name)->second;
    return ptr;
  };

  boost::shared_ptr<const Joint> getJoint(const std::string& name) const
  {
    boost::shared_ptr<const Joint> ptr;
    if (this->joints_.find(name) == this->joints_.end())
      ptr.reset();
    else
      ptr = this->joints_.find(name)->second;
    return ptr;
  };


  const std::string& getName() const {return name_;};
  void getLinks(std::vector<boost::shared_ptr<Link> >& links) const
  {
    for (std::map<std::string,boost::shared_ptr<Link> >::const_iterator link = this->links_.begin();link != this->links_.end(); link++)
    {
      links.push_back(link->second);
    }
  };

  void clear()
  {
    name_.clear();
    this->links_.clear();
    this->joints_.clear();
    this->materials_.clear();
    this->root_link_.reset();
  };

  void getLink(const std::string& name,boost::shared_ptr<Link> &link) const
  {
    boost::shared_ptr<Link> ptr;
    if (this->links_.find(name) == this->links_.end())
      ptr.reset();
    else
      ptr = this->links_.find(name)->second;
    link = ptr;
  };

  boost::shared_ptr<Material> getMaterial(const std::string& name) const
  {
    boost::shared_ptr<Material> ptr;
    if (this->materials_.find(name) == this->materials_.end())
      ptr.reset();
    else
      ptr = this->materials_.find(name)->second;
    return ptr;
  };

  bool initTree(std::map<std::string, std::string> &parent_link_tree)
  {
    // loop through all joints, for every link, assign children links and children joints
    for (std::map<std::string,boost::shared_ptr<Joint> >::iterator joint = this->joints_.begin();joint != this->joints_.end(); joint++)
    {
      std::string parent_link_name = joint->second->parent_link_name;
      std::string child_link_name = joint->second->child_link_name;

      ROS_DEBUG("build tree: joint: '%s' has parent link '%s' and child  link '%s'", joint->first.c_str(), parent_link_name.c_str(),child_link_name.c_str());
      if (parent_link_name.empty() || child_link_name.empty())
      {
        ROS_ERROR("    Joint %s is missing a parent and/or child link specification.",(joint->second)->name.c_str());
        return false;
      }
      else
      {
        // find child and parent links
        boost::shared_ptr<Link> child_link, parent_link;
        this->getLink(child_link_name, child_link);
        if (!child_link)
        {
          ROS_ERROR("    child link '%s' of joint '%s' not found", child_link_name.c_str(), joint->first.c_str() );
          return false;
        }
        this->getLink(parent_link_name, parent_link);
        if (!parent_link)
        {
          ROS_ERROR("    parent link '%s' of joint '%s' not found.  The Boxturtle urdf parser used to automatically add this link for you, but this is not valid according to the URDF spec. Every link you refer to from a joint needs to be explicitly defined in the robot description. To fix this problem you can either remove this joint from your urdf file, or add \"<link name=\"%s\" />\" to your urdf file.", parent_link_name.c_str(), joint->first.c_str(), parent_link_name.c_str() );
          return false;
        }

        //set parent link for child link
        child_link->setParent(parent_link);

        //set parent joint for child link
        child_link->setParentJoint(joint->second);

        //set child joint for parent link
        parent_link->addChildJoint(joint->second);
      
        //set child link for parent link
        parent_link->addChild(child_link);
      
        // fill in child/parent string map
        parent_link_tree[child_link->name] = parent_link_name;
      
        ROS_DEBUG("    now Link '%s' has %i children ", parent_link->name.c_str(), (int)parent_link->child_links.size());
      }
    }

    return true;
  };


  bool initRoot(std::map<std::string, std::string> &parent_link_tree)
  {
    this->root_link_.reset();

    // find the links that have no parent in the tree
    for (std::map<std::string, boost::shared_ptr<Link> >::iterator l=this->links_.begin(); l!=this->links_.end(); l++)  
    {
      std::map<std::string, std::string >::iterator parent = parent_link_tree.find(l->first);
      if (parent == parent_link_tree.end())
      {
        // store root link
        if (!this->root_link_)
        {
          getLink(l->first, this->root_link_);
        }
        // we already found a root link
        else{
          ROS_ERROR("Two root links found: '%s' and '%s'", this->root_link_->name.c_str(), l->first.c_str());
          return false;
        }
      }
    }
    if (!this->root_link_)
    {
      ROS_ERROR("No root link found. The robot xml is not a valid tree.");
      return false;
    }
    ROS_DEBUG("Link '%s' is the root link", this->root_link_->name.c_str());

    return true;
  };

  std::map<std::string, boost::shared_ptr<Link> > links_;
  std::map<std::string, boost::shared_ptr<Joint> > joints_;
  std::map<std::string, boost::shared_ptr<Material> > materials_;

  std::string name_;

  boost::shared_ptr<Link> root_link_;



};

}

#endif