flightgear/src/Input/FGJoystickInput.cxx

// FGJoystickInput.cxx -- handle user input from joystick devices
//
// Written by Torsten Dreyer, started August 2009
// Based on work from David Megginson, started May 2001.
//
// Copyright (C) 2009 Torsten Dreyer, Torsten (at) t3r _dot_ de
// Copyright (C) 2001 David Megginson, david@megginson.com
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2 of the
// License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
//
// $Id$

#include "config.h"

#include "FGJoystickInput.hxx"

#if defined(SG_WINDOWS)
#  include <windows.h>
#endif

#include <cmath>

#include <simgear/props/props_io.hxx>
#include "FGDeviceConfigurationMap.hxx"
#include <Main/fg_props.hxx>
#include <Scripting/NasalSys.hxx>

using simgear::PropertyList;

FGJoystickInput::axis::axis ()
  : last_value(9999999),
    tolerance(0.002),
    low_threshold(-0.9),
    high_threshold(0.9),
    interval_sec(0),
    delay_sec(0),
    release_delay_sec(0),
    last_dt(0)
{
}

FGJoystickInput::axis::~axis ()
{
}

FGJoystickInput::joystick::joystick ()
  : jsnum(0),
    naxes(0),
    nbuttons(0),
    axes(0),
    buttons(0),
    predefined(true)
{
}

void FGJoystickInput::joystick::clearAxesAndButtons()
{
    delete[] axes;
    delete[] buttons;
    axes = NULL;
    buttons = NULL;
    naxes = 0;
    nbuttons = 0;
}

FGJoystickInput::joystick::~joystick ()
{
  jsnum = 0;
  clearAxesAndButtons();
}


FGJoystickInput::FGJoystickInput()
{
}

FGJoystickInput::~FGJoystickInput()
{
    _remove(true);
}

void FGJoystickInput::_remove(bool all)
{
    SGPropertyNode * js_nodes = fgGetNode("/input/joysticks", true);

    for (int i = 0; i < MAX_JOYSTICKS; i++)
    {
        joystick* joy = &joysticks[i];
        // do not remove predefined joysticks info on reinit
        if (all || (!joy->predefined))
            js_nodes->removeChild("js", i);

        joy->plibJS.reset();
        joy->clearAxesAndButtons();
    }
}

void FGJoystickInput::init()
{
  jsInit();
  SG_LOG(SG_INPUT, SG_DEBUG, "Initializing joystick bindings");
  SGPropertyNode_ptr js_nodes = fgGetNode("/input/joysticks", true);
  status_node = fgGetNode("/devices/status/joysticks", true);

  FGDeviceConfigurationMap configMap("Input/Joysticks",js_nodes, "js-named");

  for (int i = 0; i < MAX_JOYSTICKS; i++) {
    jsJoystick * js = new jsJoystick(i);
    joysticks[i].plibJS.reset(js);
    joysticks[i].initializing = true;

    if (js->notWorking()) {
      SG_LOG(SG_INPUT, SG_DEBUG, "Joystick " << i << " not found");
      continue;
    }

    const char * name = js->getName();
    SGPropertyNode_ptr js_node = js_nodes->getChild("js", i);

    if (js_node) {
      SG_LOG(SG_INPUT, SG_INFO, "Using existing bindings for joystick " << i);

    } else {
      joysticks[i].predefined = false;
      SG_LOG(SG_INPUT, SG_INFO, "Looking for bindings for joystick \"" << name << '"');
      SGPropertyNode_ptr named;

      // allow distinguishing duplicated devices by the name
      string indexedName = computeDeviceIndexName(name, i);
      if (configMap.hasConfiguration(indexedName)) {
          named = configMap.configurationForDeviceName(indexedName);
          std::string source = named->getStringValue("source", "user defined");
          SG_LOG(SG_INPUT, SG_INFO, "... found joystick: " << source);
      } else if (configMap.hasConfiguration(name)) {
        named = configMap.configurationForDeviceName(name);
        std::string source = named->getStringValue("source", "user defined");
        SG_LOG(SG_INPUT, SG_INFO, "... found joystick: " << source);
      } else if ((named = configMap.configurationForDeviceName("default"))) {
        std::string source = named->getStringValue("source", "user defined");
        SG_LOG(SG_INPUT, SG_INFO, "No config found for joystick \"" << name
            << "\"\nUsing default: \"" << source << '"');

      } else {
        SG_LOG(SG_INPUT, SG_WARN, "No joystick configuration file with <name>" << name << "</name> entry found!");
      }

      js_node = js_nodes->getChild("js", i, true);
      copyProperties(named, js_node);
      js_node->setStringValue("id", name);
    }
  }
}

std::string FGJoystickInput::computeDeviceIndexName(const std::string& name,
                                                    int lastIndex) const
{
    int index = 0;
    for (int i = 0; i < lastIndex; i++) {
        if (joysticks[i].plibJS && (joysticks[i].plibJS->getName() == name)) {
            ++index;
        }
    }

    std::ostringstream os;
    os << name << "_" << index;
    return os.str();
}

void FGJoystickInput::reinit()
{
    SG_LOG(SG_INPUT, SG_DEBUG, "Re-Initializing joystick bindings");
    _remove(false);

#if defined(SG_MAC)
    jsShutdown();
#endif

    FGJoystickInput::init();
    FGJoystickInput::postinit();
}

void FGJoystickInput::postinit()
{
  FGNasalSys *nasalsys = (FGNasalSys *)globals->get_subsystem("nasal");
  SGPropertyNode_ptr js_nodes = fgGetNode("/input/joysticks");

  for (int i = 0; i < MAX_JOYSTICKS; i++) {
    SGPropertyNode_ptr js_node = js_nodes->getChild("js", i);
    jsJoystick *js = joysticks[i].plibJS.get();
    if (!js_node || js->notWorking())
      continue;

#ifdef WIN32
    JOYCAPS jsCaps ;
    joyGetDevCaps( i, &jsCaps, sizeof(jsCaps) );
    unsigned int nbuttons = jsCaps.wNumButtons;
    if (nbuttons > MAX_JOYSTICK_BUTTONS) nbuttons = MAX_JOYSTICK_BUTTONS;
#else
    unsigned int nbuttons = MAX_JOYSTICK_BUTTONS;
#endif

    int naxes = js->getNumAxes();
    if (naxes > MAX_JOYSTICK_AXES) naxes = MAX_JOYSTICK_AXES;
    joysticks[i].naxes = naxes;
    joysticks[i].nbuttons = nbuttons;

    SG_LOG(SG_INPUT, SG_DEBUG, "Initializing joystick " << i);

                                // Set up range arrays
    float minRange[MAX_JOYSTICK_AXES];
    float maxRange[MAX_JOYSTICK_AXES];
    float center[MAX_JOYSTICK_AXES];

                                // Initialize with default values
    js->getMinRange(minRange);
    js->getMaxRange(maxRange);
    js->getCenter(center);

                                // Allocate axes and buttons
    joysticks[i].axes = new axis[naxes];
    joysticks[i].buttons = new FGButton[nbuttons];

    //
    // Initialize nasal groups.
    //
    std::ostringstream str;
    str << "__js" << i;
    std::string module = str.str();
    nasalsys->createModule(module.c_str(), module.c_str(), "", 0);

    PropertyList nasal = js_node->getChildren("nasal");
    unsigned int j;
    for (j = 0; j < nasal.size(); j++) {
      nasal[j]->setStringValue("module", module.c_str());
      nasalsys->handleCommand(nasal[j],nullptr);
    }

    //
    // Initialize the axes.
    //
    PropertyList axes = js_node->getChildren("axis");
    size_t nb_axes = axes.size();
    for (j = 0; j < nb_axes; j++ ) {
      const SGPropertyNode * axis_node = axes[j];
      const SGPropertyNode * num_node = axis_node->getChild("number");
      int n_axis = axis_node->getIndex();
      if (num_node != 0) {
          n_axis = num_node->getIntValue(TGT_PLATFORM, -1);

        #ifdef SG_MAC
          // Mac falls back to Unix by default - avoids specifying many
          // duplicate <mac> entries in joystick config files
          if (n_axis < 0) {
              n_axis = num_node->getIntValue("unix", -1);
          }
        #endif

          // Silently ignore platforms that are not specified within the
          // <number></number> section
          if (n_axis < 0) {
              continue;
          }
      }

      if (n_axis >= naxes) {
          SG_LOG(SG_INPUT, SG_DEBUG, "Dropping bindings for axis " << n_axis);
          continue;
      }
      axis &a = joysticks[i].axes[n_axis];

      js->setDeadBand(n_axis, axis_node->getDoubleValue("dead-band", 0.0));

      a.tolerance = axis_node->getDoubleValue("tolerance", 0.002);
      minRange[n_axis] = axis_node->getDoubleValue("min-range", minRange[n_axis]);
      maxRange[n_axis] = axis_node->getDoubleValue("max-range", maxRange[n_axis]);
      center[n_axis] = axis_node->getDoubleValue("center", center[n_axis]);

      read_bindings(axis_node, a.bindings, KEYMOD_NONE, module );

      // Initialize the virtual axis buttons.
      a.low.init(axis_node->getChild("low"), "low", module );
      a.low_threshold = axis_node->getDoubleValue("low-threshold", -0.9);

      a.high.init(axis_node->getChild("high"), "high", module );
      a.high_threshold = axis_node->getDoubleValue("high-threshold", 0.9);
      a.interval_sec = axis_node->getDoubleValue("interval-sec",0.0);
      a.delay_sec = axis_node->getDoubleValue("delay-sec",0.0);
      a.release_delay_sec = axis_node->getDoubleValue("release-delay-sec",0.0);
      a.last_dt = 0.0;
    }

    //
    // Initialize the buttons.
    //
    PropertyList buttons = js_node->getChildren("button");
    for (auto button_node : buttons ) {
      size_t n_but = button_node->getIndex();

      const SGPropertyNode * num_node = button_node->getChild("number");
      if (NULL != num_node)
          n_but = num_node->getIntValue(TGT_PLATFORM,n_but);

      if (n_but >= nbuttons) {
          SG_LOG(SG_INPUT, SG_DEBUG, "Dropping bindings for button " << n_but);
          continue;
      }

      std::ostringstream buf;
      buf << (unsigned)n_but;

      SG_LOG(SG_INPUT, SG_DEBUG, "Initializing button " << buf.str());
      FGButton &b = joysticks[i].buttons[n_but];
      b.init(button_node, buf.str(), module );
      // get interval-sec property
      b.interval_sec = button_node->getDoubleValue("interval-sec",0.0);
      b.delay_sec = button_node->getDoubleValue("delay-sec",0.0);
      b.release_delay_sec = button_node->getDoubleValue("release-delay-sec",0.0);
      b.last_dt = 0.0;
    }

    js->setMinRange(minRange);
    js->setMaxRange(maxRange);
    js->setCenter(center);
  }
}

void FGJoystickInput::updateJoystick(int index, FGJoystickInput::joystick* joy, double dt)
{
  float axis_values[MAX_JOYSTICK_AXES];
  int modifiers = fgGetKeyModifiers();
  int buttons;
  bool pressed, last_state;
  bool axes_initialized;
  float delay;

  jsJoystick * js = joy->plibJS.get();
  if (js == 0 || js->notWorking()) {
    joysticks[index].initializing = true;
    if (js) {
      joysticks[index].init_dt += dt;
      if (joysticks[index].init_dt >= 1.0) {
        joysticks[index].plibJS.reset( new jsJoystick(index) );
        joysticks[index].init_dt = 0.0;
      }
    }
    return;
  }

  js->read(&buttons, axis_values);
  if (js->notWorking()) { // If js is disconnected
    joysticks[index].initializing = true;
    return;
  }

  // Joystick axes can get initialized to extreme values, at least on Linux.
  // Wait until one of the axes get a different value before continuing.
  // https://sourceforge.net/p/flightgear/codetickets/2185/
  axes_initialized = true;
  if (joysticks[index].initializing) {

    if (!joysticks[index].initialized) {
      js->read(NULL, joysticks[index].values);
      joysticks[index].initialized = true;
    }

    int j;
    for (j = 0; j < joy->naxes; j++) {
      if (axis_values[j] != joysticks[index].values[j]) break;
    }
    if (j < joy->naxes) {
      joysticks[index].initializing = false;
    } else {
      axes_initialized = false;
    }
  }

  // Update device status
  SGPropertyNode_ptr status = status_node->getChild("joystick", index, true);
  if (axes_initialized) {
    for (int j = 0; j < MAX_JOYSTICK_AXES; j++) {
      status->getChild("axis", j, true)->setFloatValue(axis_values[j]);
    }
  }

  for (int j = 0; j < MAX_JOYSTICK_BUTTONS; j++) {
    status->getChild("button", j, true)->setBoolValue((buttons & (1u << j)) > 0 );
  }

  // Fire bindings for the axes.
  if (axes_initialized) {
    for (int j = 0; j < joy->naxes; j++) {
      axis &a = joy->axes[j];

      // Do nothing if the axis position
      // is unchanged; only a change in
      // position fires the bindings.
      // But only if there are bindings
      if (fabs(axis_values[j] - a.last_value) > a.tolerance
          && a.bindings[KEYMOD_NONE].size() > 0 ) {
        a.last_value = axis_values[j];
        for (unsigned int k = 0; k < a.bindings[KEYMOD_NONE].size(); k++)
          a.bindings[KEYMOD_NONE][k]->fire(axis_values[j]);
      }

      // do we have to emulate axis buttons?
      last_state = joy->axes[j].low.last_state || joy->axes[j].high.last_state;
      pressed = axis_values[j] < a.low_threshold || axis_values[j] > a.high_threshold;
      delay = (pressed ? last_state ? a.interval_sec : a.delay_sec : a.release_delay_sec );
      if(pressed || last_state) a.last_dt += dt;
      else a.last_dt = 0;
      if(a.last_dt >= delay) {
        if (a.low.bindings[modifiers].size())
          joy->axes[j].low.update( modifiers, axis_values[j] < a.low_threshold );

        if (a.high.bindings[modifiers].size())
          joy->axes[j].high.update( modifiers, axis_values[j] > a.high_threshold );

        a.last_dt -= delay;
      }
    } // of axes iteration
  } // axes_initialized

  // Fire bindings for the buttons.
  for (int j = 0; j < joy->nbuttons; j++) {
    FGButton &b = joy->buttons[j];
    pressed = (buttons & (1u << j)) > 0;
    last_state = joy->buttons[j].last_state;
    delay = (pressed ? last_state ? b.interval_sec : b.delay_sec : b.release_delay_sec );
    if(pressed || last_state) b.last_dt += dt;
    else b.last_dt = 0;
    if(b.last_dt >= delay) {
      joy->buttons[j].update( modifiers, pressed );
      b.last_dt -= delay;
    }
  } // of butotns iterations

}

void FGJoystickInput::update( double dt )
{
  for (int i = 0; i < MAX_JOYSTICKS; i++) {
    updateJoystick(i, &joysticks[i], dt);
  }
}


// Register the subsystem.
SGSubsystemMgr::Registrant<FGJoystickInput> registrantFGJoystickInput(
    SGSubsystemMgr::GENERAL,
    {{"nasal", SGSubsystemMgr::Dependency::HARD}});