---

panda/src/vrpn/vrpnClient.cxx

Go to the documentation of this file.

// Filename: vrpnClient.cxx
// Created by:  jason (04Aug00)
//
////////////////////////////////////////////////////////////////////
//
// PANDA 3D SOFTWARE
// Copyright (c) 2001, Disney Enterprises, Inc.  All rights reserved
//
// All use of this software is subject to the terms of the Panda 3d
// Software license.  You should have received a copy of this license
// along with this source code; you will also find a current copy of
// the license at http://www.panda3d.org/license.txt .
//
// To contact the maintainers of this program write to
// panda3d@yahoogroups.com .
//
////////////////////////////////////////////////////////////////////

#include "vrpnClient.h"
#include "vrpnTracker.h"
#include "vrpnTrackerDevice.h"
#include "vrpnButton.h"
#include "vrpnButtonDevice.h"
#include "vrpnAnalog.h"
#include "vrpnAnalogDevice.h"
#include "vrpnDial.h"
#include "vrpnDialDevice.h"
#include "config_vrpn.h"

#include "dcast.h"
#include "string_utils.h"
#include "indent.h"

TypeHandle VrpnClient::_type_handle;

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::Constructor
//       Access: Public
//  Description:
////////////////////////////////////////////////////////////////////
VrpnClient::
VrpnClient(const string &server_name) :
  _server_name(server_name)
{
  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Attempting to connect to VRPN server " << _server_name
      << "\n";
  }
  _connection = vrpn_get_connection_by_name(_server_name.c_str());
  nassertv(_connection != (vrpn_Connection *)NULL);

  if (!is_valid()) {
    vrpn_cat.warning()
      << "Unable to establish connection to VRPN server " << _server_name
      << "\n";
  }
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::Constructor
//       Access: Public
//  Description:
////////////////////////////////////////////////////////////////////
VrpnClient::
~VrpnClient() {
  delete _connection;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::write
//       Access: Public
//  Description: Writes a list of the active devices that the
//               VrpnClient is currently polling each frame.
////////////////////////////////////////////////////////////////////
void VrpnClient::
write(ostream &out, int indent_level) const {
  indent(out, indent_level)
    << "VrpnClient, server " << _server_name << "\n";

  if (!is_valid()) {
    indent(out, indent_level + 2)
      << "(error)\n";
  } else if (!is_connected()) {
    indent(out, indent_level + 2)
      << "(no connection)\n";
  }

  if (!_trackers.empty()) {
    indent(out, indent_level + 2)
      << _trackers.size() << " trackers:\n";
    Trackers::const_iterator ti;
    for (ti = _trackers.begin(); ti != _trackers.end(); ++ti) {
      VrpnTracker *vrpn_tracker = (*ti).second;
      vrpn_tracker->write(out, indent_level + 4);
    }
  }

  if (!_buttons.empty()) {
    indent(out, indent_level + 2)
      << _buttons.size() << " buttons:\n";
    Buttons::const_iterator bi;
    for (bi = _buttons.begin(); bi != _buttons.end(); ++bi) {
      VrpnButton *vrpn_button = (*bi).second;
      vrpn_button->write(out, indent_level + 4);
    }
  }

  if (!_analogs.empty()) {
    indent(out, indent_level + 2)
      << _analogs.size() << " analogs:\n";
    Analogs::const_iterator ai;
    for (ai = _analogs.begin(); ai != _analogs.end(); ++ai) {
      VrpnAnalog *vrpn_analog = (*ai).second;
      vrpn_analog->write(out, indent_level + 4);
    }
  }

  if (!_dials.empty()) {
    indent(out, indent_level + 2)
      << _dials.size() << " dials:\n";
    Dials::const_iterator di;
    for (di = _dials.begin(); di != _dials.end(); ++di) {
      VrpnDial *vrpn_dial = (*di).second;
      vrpn_dial->write(out, indent_level + 4);
    }
  }
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::make_device
//       Access: Protected, Virtual
//  Description: Creates and returns a new ClientDevice of the
//               appropriate type, according to the requested
//               device_type and device_name.  Returns NULL if a
//               matching device cannot be found.
//
//               This is guaranteed not to be called twice for a given
//               device_type/device_name combination (unless
//               disconnect_device() has already been called for the
//               same device_type/device_name).
////////////////////////////////////////////////////////////////////
PT(ClientDevice) VrpnClient::
make_device(TypeHandle device_type, const string &device_name) {
  if (device_type == ClientTrackerDevice::get_class_type()) {
    return make_tracker_device(device_name);

  } else if (device_type == ClientButtonDevice::get_class_type()) {
    return make_button_device(device_name);

  } else if (device_type == ClientAnalogDevice::get_class_type()) {
    return make_analog_device(device_name);

  } else if (device_type == ClientDialDevice::get_class_type()) {
    return make_dial_device(device_name);

  } else {
    return NULL;
  }
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::disconnect_device
//       Access: Protected, Virtual
//  Description: Removes the device, which is presumably about to
//               destruct, from the list of connected devices, and
//               frees any data required to support it.  This device
//               will no longer receive automatic updates with each
//               poll.
//
//               The return value is true if the device was
//               disconnected, or false if it was unknown (e.g. it was
//               disconnected previously).
////////////////////////////////////////////////////////////////////
bool VrpnClient::
disconnect_device(TypeHandle device_type, const string &device_name,
                  ClientDevice *device) {
  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Disconnecting device " << *device << "\n";
  }

  if (ClientBase::disconnect_device(device_type, device_name, device)) {
    if (device->is_of_type(VrpnTrackerDevice::get_class_type())) {
      disconnect_tracker_device(DCAST(VrpnTrackerDevice, device));

    } else if (device->is_of_type(VrpnButtonDevice::get_class_type())) {
      disconnect_button_device(DCAST(VrpnButtonDevice, device));

    } else if (device->is_of_type(VrpnAnalogDevice::get_class_type())) {
      disconnect_analog_device(DCAST(VrpnAnalogDevice, device));

    } else if (device->is_of_type(VrpnDialDevice::get_class_type())) {
      disconnect_dial_device(DCAST(VrpnDialDevice, device));

    }
    return true;
  }

  return false;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::do_poll
//       Access: Protected, Virtual
//  Description: Implements the polling and updating of connected
//               devices, if the ClientBase requires this.  This may
//               be called in a sub-thread if
//               fork_asynchronous_thread() was called; otherwise, it
//               will be called once per frame.
////////////////////////////////////////////////////////////////////
void VrpnClient::
do_poll() {
  ClientBase::do_poll();

  if (vrpn_cat.is_spam()) {
    vrpn_cat.spam()
      << "VrpnClient " << _server_name << " polling "
      << _trackers.size() + _buttons.size() + _analogs.size() + _dials.size()
      << " devices.\n";
  }

  Trackers::iterator ti;
  for (ti = _trackers.begin(); ti != _trackers.end(); ++ti) {
    VrpnTracker *vrpn_tracker = (*ti).second;
    vrpn_tracker->poll();
  }

  Buttons::iterator bi;
  for (bi = _buttons.begin(); bi != _buttons.end(); ++bi) {
    VrpnButton *vrpn_button = (*bi).second;
    vrpn_button->poll();
  }

  Analogs::iterator ai;
  for (ai = _analogs.begin(); ai != _analogs.end(); ++ai) {
    VrpnAnalog *vrpn_analog = (*ai).second;
    vrpn_analog->poll();
  }

  Dials::iterator di;
  for (di = _dials.begin(); di != _dials.end(); ++di) {
    VrpnDial *vrpn_dial = (*di).second;
    vrpn_dial->poll();
  }
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::make_tracker_device
//       Access: Private
//  Description: Creates a new tracker device.  The device_name is
//               parsed for sensor and data_type information.
//
//               The device_name may be one of the following:
//
//                    tracker_name
//                    tracker_name:N
//                    tracker_name:N[pva]
//
//               Where N is an integer sensor number, and [pva] is one
//               of the lowercase letters p, v, or a.
//
//               In the first form, the device connects to the
//               indicated tracker, and reports position information
//               on sensor number 0.
//
//               In the second form, the device connects to the
//               indicated tracker, and reports position information
//               on the indicated sensor number.
//
//               In the third form, the device connects to the
//               indicated tracker, and reports either position,
//               velocity, or acceleration information on the
//               indicated sensor number.
////////////////////////////////////////////////////////////////////
PT(ClientDevice) VrpnClient::
make_tracker_device(const string &device_name) {
  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Making tracker device for " << device_name << "\n";
  }

  string tracker_name = device_name;
  int sensor = 0;
  VrpnTrackerDevice::DataType data_type = VrpnTrackerDevice::DT_position;

  size_t colon = device_name.rfind(':');
  if (colon != string::npos && colon + 1 < device_name.length()) {
    size_t begin = colon + 1;
    size_t end = device_name.length();
    VrpnTrackerDevice::DataType maybe_data_type = data_type;

    switch (device_name[end - 1]) {
    case 'p':
      maybe_data_type = VrpnTrackerDevice::DT_position;
      end--;
      break;

    case 'v':
      maybe_data_type = VrpnTrackerDevice::DT_velocity;
      end--;
      break;

    case 'a':
      maybe_data_type = VrpnTrackerDevice::DT_acceleration;
      end--;
      break;
    }
    int maybe_sensor;
    if (string_to_int(device_name.substr(begin, end - begin), maybe_sensor)) {
      // It seems to be a legitimate integer!
      sensor = maybe_sensor;
      data_type = maybe_data_type;
      tracker_name = device_name.substr(0, colon);
    }
  }

  VrpnTracker *tracker = get_tracker(tracker_name);

  VrpnTrackerDevice *device =
    new VrpnTrackerDevice(this, device_name, sensor, data_type, tracker);

  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Creating " << *device << "\n";
  }

  tracker->mark(device);
  return device;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::make_button_device
//       Access: Private
//  Description: Creates a new button device.  The device_name is sent
//               verbatim to the VRPN library.
////////////////////////////////////////////////////////////////////
PT(ClientDevice) VrpnClient::
make_button_device(const string &device_name) {
  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Making button device for " << device_name << "\n";
  }

  VrpnButton *button = get_button(device_name);

  VrpnButtonDevice *device =
    new VrpnButtonDevice(this, device_name, button);

  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Creating " << *device << "\n";
  }

  button->mark(device);
  return device;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::make_analog_device
//       Access: Private
//  Description: Creates a new analog device.  The device_name is sent
//               verbatim to the VRPN library.
////////////////////////////////////////////////////////////////////
PT(ClientDevice) VrpnClient::
make_analog_device(const string &device_name) {
  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Making analog device for " << device_name << "\n";
  }

  VrpnAnalog *analog = get_analog(device_name);

  VrpnAnalogDevice *device =
    new VrpnAnalogDevice(this, device_name, analog);

  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Creating " << *device << "\n";
  }

  analog->mark(device);
  return device;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::make_dial_device
//       Access: Private
//  Description: Creates a new dial device.  The device_name is sent
//               verbatim to the VRPN library.
////////////////////////////////////////////////////////////////////
PT(ClientDevice) VrpnClient::
make_dial_device(const string &device_name) {
  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Making dial device for " << device_name << "\n";
  }

  VrpnDial *dial = get_dial(device_name);

  VrpnDialDevice *device =
    new VrpnDialDevice(this, device_name, dial);

  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Creating " << *device << "\n";
  }

  dial->mark(device);
  return device;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::disconnect_tracker_device
//       Access: Private
//  Description: Removes the tracker device from the list of things to
//               be updated.
////////////////////////////////////////////////////////////////////
void VrpnClient::
disconnect_tracker_device(VrpnTrackerDevice *device) {
  VrpnTracker *vrpn_tracker = device->get_vrpn_tracker();
  vrpn_tracker->unmark(device);
  if (vrpn_tracker->is_empty()) {
    free_tracker(vrpn_tracker);
  }
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::disconnect_button_device
//       Access: Private
//  Description: Removes the button device from the list of things to
//               be updated.
////////////////////////////////////////////////////////////////////
void VrpnClient::
disconnect_button_device(VrpnButtonDevice *device) {
  VrpnButton *vrpn_button = device->get_vrpn_button();
  vrpn_button->unmark(device);
  if (vrpn_button->is_empty()) {
    free_button(vrpn_button);
  }
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::disconnect_analog_device
//       Access: Private
//  Description: Removes the analog device from the list of things to
//               be updated.
////////////////////////////////////////////////////////////////////
void VrpnClient::
disconnect_analog_device(VrpnAnalogDevice *device) {
  VrpnAnalog *vrpn_analog = device->get_vrpn_analog();
  vrpn_analog->unmark(device);
  if (vrpn_analog->is_empty()) {
    free_analog(vrpn_analog);
  }
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::disconnect_dial_device
//       Access: Private
//  Description: Removes the dial device from the list of things to
//               be updated.
////////////////////////////////////////////////////////////////////
void VrpnClient::
disconnect_dial_device(VrpnDialDevice *device) {
  VrpnDial *vrpn_dial = device->get_vrpn_dial();
  vrpn_dial->unmark(device);
  if (vrpn_dial->is_empty()) {
    free_dial(vrpn_dial);
  }
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::get_tracker
//       Access: Private
//  Description: Finds a VrpnTracker of the indicated name, and
//               returns it if one already exists, or creates a new
//               one if it does not.
////////////////////////////////////////////////////////////////////
VrpnTracker *VrpnClient::
get_tracker(const string &tracker_name) {
  Trackers::iterator ti;
  ti = _trackers.find(tracker_name);

  if (ti != _trackers.end()) {
    return (*ti).second;
  }

  VrpnTracker *vrpn_tracker = new VrpnTracker(tracker_name, _connection);
  _trackers.insert(Trackers::value_type(tracker_name, vrpn_tracker));

  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Creating tracker " << *vrpn_tracker << "\n";
  }

  return vrpn_tracker;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::free_tracker
//       Access: Private
//  Description: Removes and deletes the indicated VrpnTracker, which
//               is no longer referenced by any VrpnTrackerDevices.
////////////////////////////////////////////////////////////////////
void VrpnClient::
free_tracker(VrpnTracker *vrpn_tracker) {
  nassertv(vrpn_tracker->is_empty());

  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Deleting tracker " << *vrpn_tracker << "\n";
  }

  Trackers::iterator ti;
  ti = _trackers.find(vrpn_tracker->get_tracker_name());
  nassertv(ti != _trackers.end());
  nassertv((*ti).second == vrpn_tracker);

  _trackers.erase(ti);
  delete vrpn_tracker;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::get_button
//       Access: Private
//  Description: Finds a VrpnButton of the indicated name, and
//               returns it if one already exists, or creates a new
//               one if it does not.
////////////////////////////////////////////////////////////////////
VrpnButton *VrpnClient::
get_button(const string &button_name) {
  Buttons::iterator bi;
  bi = _buttons.find(button_name);

  if (bi != _buttons.end()) {
    return (*bi).second;
  }

  VrpnButton *vrpn_button = new VrpnButton(button_name, _connection);
  _buttons.insert(Buttons::value_type(button_name, vrpn_button));

  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Creating button " << *vrpn_button << "\n";
  }

  return vrpn_button;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::free_button
//       Access: Private
//  Description: Removes and deletes the indicated VrpnButton, which
//               is no longer referenced by any VrpnButtonDevices.
////////////////////////////////////////////////////////////////////
void VrpnClient::
free_button(VrpnButton *vrpn_button) {
  nassertv(vrpn_button->is_empty());

  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Deleting button " << *vrpn_button << "\n";
  }

  Buttons::iterator bi;
  bi = _buttons.find(vrpn_button->get_button_name());
  nassertv(bi != _buttons.end());
  nassertv((*bi).second == vrpn_button);

  _buttons.erase(bi);
  delete vrpn_button;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::get_analog
//       Access: Private
//  Description: Finds a VrpnAnalog of the indicated name, and
//               returns it if one already exists, or creates a new
//               one if it does not.
////////////////////////////////////////////////////////////////////
VrpnAnalog *VrpnClient::
get_analog(const string &analog_name) {
  Analogs::iterator ai;
  ai = _analogs.find(analog_name);

  if (ai != _analogs.end()) {
    return (*ai).second;
  }

  VrpnAnalog *vrpn_analog = new VrpnAnalog(analog_name, _connection);
  _analogs.insert(Analogs::value_type(analog_name, vrpn_analog));

  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Creating analog " << *vrpn_analog << "\n";
  }

  return vrpn_analog;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::free_analog
//       Access: Private
//  Description: Removes and deletes the indicated VrpnAnalog, which
//               is no longer referenced by any VrpnAnalogDevices.
////////////////////////////////////////////////////////////////////
void VrpnClient::
free_analog(VrpnAnalog *vrpn_analog) {
  nassertv(vrpn_analog->is_empty());

  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Deleting analog " << *vrpn_analog << "\n";
  }

  Analogs::iterator ai;
  ai = _analogs.find(vrpn_analog->get_analog_name());
  nassertv(ai != _analogs.end());
  nassertv((*ai).second == vrpn_analog);

  _analogs.erase(ai);
  delete vrpn_analog;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::get_dial
//       Access: Private
//  Description: Finds a VrpnDial of the indicated name, and
//               returns it if one already exists, or creates a new
//               one if it does not.
////////////////////////////////////////////////////////////////////
VrpnDial *VrpnClient::
get_dial(const string &dial_name) {
  Dials::iterator di;
  di = _dials.find(dial_name);

  if (di != _dials.end()) {
    return (*di).second;
  }

  VrpnDial *vrpn_dial = new VrpnDial(dial_name, _connection);
  _dials.insert(Dials::value_type(dial_name, vrpn_dial));

  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Creating dial " << *vrpn_dial << "\n";
  }

  return vrpn_dial;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::free_dial
//       Access: Private
//  Description: Removes and deletes the indicated VrpnDial, which
//               is no longer referenced by any VrpnDialDevices.
////////////////////////////////////////////////////////////////////
void VrpnClient::
free_dial(VrpnDial *vrpn_dial) {
  nassertv(vrpn_dial->is_empty());

  if (vrpn_cat.is_debug()) {
    vrpn_cat.debug()
      << "Deleting dial " << *vrpn_dial << "\n";
  }

  Dials::iterator di;
  di = _dials.find(vrpn_dial->get_dial_name());
  nassertv(di != _dials.end());
  nassertv((*di).second == vrpn_dial);

  _dials.erase(di);
  delete vrpn_dial;
}


#if 0

#include <datagram.h>
#include <datagramIterator.h>

typedef struct {
  string device_name;
  void *self;
} VrpnClientInfo;


////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::add_remote_tracker
//       Access: Public, Virtual
//  Description: Creates a new vrpn remote tracker object and registers
//               a callback with it.
////////////////////////////////////////////////////////////////////
bool VrpnClient::
add_remote_tracker(const string &tracker, int sensor) {

  vrpn_Tracker_Remote *vrpn_tracker = new vrpn_Tracker_Remote(tracker.c_str(), _connection);
  if (vrpn_tracker == (vrpn_Tracker_Remote *)NULL) {
    return false;
  }

  //Now package up the information that needs to be passed to the
  //callback function to allow it to determine for which tracker we
  //are receiving information for
  VrpnClientInfo *data = new VrpnClientInfo;
  data->device_name = tracker;
  data->self = this;

  vrpn_tracker->register_change_handler((void*)data, st_tracker_position);
  vrpn_tracker->register_change_handler((void*)data, st_tracker_velocity);
  vrpn_tracker->register_change_handler((void*)data, st_tracker_acceleration);

  _vrpn_trackers[tracker] = vrpn_tracker;
  _trackers.push_back(tracker);
  _sensors[tracker].push_back(sensor);

  return true;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::add_remote_analog
//       Access: Public, Virtual
//  Description: Creates a new vrpn remote analog object and registers
//               a callback with it.
////////////////////////////////////////////////////////////////////
bool VrpnClient::
add_remote_analog(const string &analog) {

  vrpn_Analog_Remote *vrpn_analog = new vrpn_Analog_Remote(analog.c_str(), _connection);
  if (vrpn_analog == (vrpn_Analog_Remote *)NULL) {
    return false;
  }

  //Now package up the information that needs to be passed to the
  //callback function to allow it to determine for which analog we
  //are receiving information for
  VrpnClientInfo *data = new VrpnClientInfo;
  data->device_name = analog;
  data->self = this;

  vrpn_analog->register_change_handler((void*)data, st_analog);

  _vrpn_analogs[analog] = vrpn_analog;
  _analogs.push_back(analog);

  return true;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::add_remote_button
//       Access: Public, Virtual
//  Description: Creates a new vrpn remote button object and registers
//               a callback with it.
////////////////////////////////////////////////////////////////////
bool VrpnClient::
add_remote_button(const string &button) {

  vrpn_Button_Remote *vrpn_button = new vrpn_Button_Remote(button.c_str(), _connection);
  if (vrpn_button == (vrpn_Button_Remote *)NULL) {
    return false;
  }

  //Now package up the information that needs to be passed to the
  //callback function to allow it to determine for which button we
  //are receiving information for
  VrpnClientInfo *data = new VrpnClientInfo;
  data->device_name = button;
  data->self = this;

  vrpn_button->register_change_handler((void*)data, st_button);

  _vrpn_buttons[button] = vrpn_button;
  _buttons.push_back(button);

  return true;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::add_remote_dial
//       Access: Public, Virtual
//  Description: Creates a new vrpn remote dial object and registers
//               a callback with it.
////////////////////////////////////////////////////////////////////
bool VrpnClient::
add_remote_dial(const string &dial) {

  vrpn_Dial_Remote *vrpn_dial = new vrpn_Dial_Remote(dial.c_str(), _connection);
  if (vrpn_dial == (vrpn_Dial_Remote *)NULL) {
    return false;
  }

  //Now package up the information that needs to be passed to the
  //callback function to allow it to determine for which dial we
  //are receiving information for
  VrpnClientInfo *data = new VrpnClientInfo;
  data->device_name = dial;
  data->self = this;

  vrpn_dial->register_change_handler((void*)data, st_dial);

  _vrpn_dials[dial] = vrpn_dial;
  _dials.push_back(dial);

  return true;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::max_analog_channels
//       Access: Public, Virtual
//  Description: Max number of analog channels
////////////////////////////////////////////////////////////////////
int VrpnClient::
max_analog_channels() {
  return vrpn_CHANNEL_MAX;
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::poll_trackers
//       Access: Public, Virtual
//  Description: Calls mainloop for the registered tracker object
//         Note: In a non-threaded case, this may need to come up with
//               some kind of cacheing scheme so we don't call mainloop
//               multiple times when a user is just asking for the data
//               of multiple sensors on 1 tracker (as that is the interface
//               supported).  This is a non-trivial problem as it is
//               difficult to know when we should and shouldn't cache.
////////////////////////////////////////////////////////////////////
void VrpnClient::
poll_tracker(const string &tracker) {
  _vrpn_trackers[tracker]->mainloop();
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::poll_analog
//       Access: Public, Virtual
//  Description: Calls mainloop for the registered analog object
////////////////////////////////////////////////////////////////////
void VrpnClient::
poll_analog(const string &analog) {
  _vrpn_analogs[analog]->mainloop();
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::poll_button
//       Access: Public, Virtual
//  Description: Calls mainloop for the registered button object
////////////////////////////////////////////////////////////////////
void VrpnClient::
poll_button(const string &button) {
  _vrpn_buttons[button]->mainloop();
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::poll_dial
//       Access: Public, Virtual
//  Description: Calls mainloop for the registered dial object
////////////////////////////////////////////////////////////////////
void VrpnClient::
poll_dial(const string &dial) {
  _vrpn_dials[dial]->mainloop();
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::st_tracker_position
//       Access: Private, Static
//  Description: Callback function that merely passes the data down
//               to the appropriate non-static function
////////////////////////////////////////////////////////////////////
void VrpnClient::
st_tracker_position(void *userdata, const vrpn_TRACKERCB info) {
  VrpnClientInfo *data = (VrpnClientInfo *)userdata;
  ((VrpnClient *)data->self)->tracker_position(data->device_name, info);
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::st_tracker_velocity
//       Access: Private, Static
//  Description: Callback function that merely passes the data down
//               to the appropriate non-static function
////////////////////////////////////////////////////////////////////
void VrpnClient::
st_tracker_velocity(void *userdata, const vrpn_TRACKERVELCB info) {
  VrpnClientInfo *data = (VrpnClientInfo *)userdata;
  ((VrpnClient *)data->self)->tracker_velocity(data->device_name, info);
}
////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::st_tracker_acceleration
//       Access: Private, Static
//  Description: Callback function that merely passes the data down
//               to the appropriate non-static function
////////////////////////////////////////////////////////////////////
void VrpnClient::
st_tracker_acceleration(void *userdata, const vrpn_TRACKERACCCB info) {
  VrpnClientInfo *data = (VrpnClientInfo *)userdata;
  ((VrpnClient *)data->self)->tracker_acceleration(data->device_name, info);
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::st_analog
//       Access: Private, Static
//  Description: Callback function that merely passes the data down
//               to the appropriate non-static function
////////////////////////////////////////////////////////////////////
void VrpnClient::
st_analog(void *userdata, const vrpn_ANALOGCB info) {
  VrpnClientInfo *data = (VrpnClientInfo *)userdata;
  ((VrpnClient *)data->self)->analog(data->device_name, info);
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::st_button
//       Access: Private, Static
//  Description: Callback function that merely passes the data down
//               to the appropriate non-static function
////////////////////////////////////////////////////////////////////
void VrpnClient::
st_button(void *userdata, const vrpn_BUTTONCB info) {
  VrpnClientInfo *data = (VrpnClientInfo *)userdata;
  ((VrpnClient *)data->self)->button(data->device_name, info);
}

////////////////////////////////////////////////////////////////////
//     Function: VrpnClient::st_dial
//       Access: Private, Static
//  Description: Callback function that merely passes the data down
//               to the appropriate non-static function
////////////////////////////////////////////////////////////////////
void VrpnClient::
st_dial(void *userdata, const vrpn_DIALCB info) {
  VrpnClientInfo *data = (VrpnClientInfo *)userdata;
  ((VrpnClient *)data->self)->dial(data->device_name, info);
}

#endif

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