CJoystick.cpp

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/* +---------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)               |
   |                          http://www.mrpt.org/                             |
   |                                                                           |
   | Copyright (c) 2005-2017, Individual contributors, see AUTHORS file        |
   | See: http://www.mrpt.org/Authors - All rights reserved.                   |
   | Released under BSD License. See details in http://www.mrpt.org/License    |
   +---------------------------------------------------------------------------+ */

#include "hwdrivers-precomp.h"   // Precompiled headers


#include <mrpt/config.h>

#ifdef MRPT_OS_WINDOWS
        #include <windows.h>
        #include <mmsystem.h>

        #if !defined(__GNUC__)
        #       pragma comment (lib,"WINMM.LIB")
        #endif
#endif

#if defined(MRPT_OS_LINUX) || defined(MRPT_OS_APPLE)
        // Linux
        #include <sys/ioctl.h>
        #include <sys/time.h>
        #include <sys/types.h>
        #include <stdlib.h>
        #include <fcntl.h>
        #include <unistd.h>
        #include <stdio.h>
        #include <errno.h>
        #include <string.h>
        #include <stdlib.h>
        #include <stdint.h>

        #if defined(MRPT_OS_LINUX) && defined(HAVE_LINUX_INPUT_H)
                #include <linux/input.h>
                #include <linux/joystick.h>
        #endif
#endif

#include <mrpt/hwdrivers/CJoystick.h>

using namespace mrpt::hwdrivers;

/*---------------------------------------------------------------
                                        Constructor
 ---------------------------------------------------------------*/
CJoystick::CJoystick()
#if defined(MRPT_OS_LINUX) && defined(HAVE_LINUX_INPUT_H)
   :
        m_joy_fd                (-1),
        m_joy_index             (-1)
#endif
{
        setLimits();
}

/*---------------------------------------------------------------
                                        Destructor
 ---------------------------------------------------------------*/
CJoystick::~CJoystick()
{
#if defined(MRPT_OS_LINUX) && defined(HAVE_LINUX_INPUT_H)
        // Close joystick, if open:
        if (m_joy_fd>0)
        {
                close(m_joy_fd);
                m_joy_fd = -1;
        }
#endif
}

/*---------------------------------------------------------------
                                        getJoysticksCount
  Returns the number of Joysticks in the computer.
 ---------------------------------------------------------------*/
int  CJoystick::getJoysticksCount()
{
        MRPT_START
#ifdef MRPT_OS_WINDOWS
        return joyGetNumDevs();
#elif defined(MRPT_OS_LINUX) && defined(HAVE_LINUX_INPUT_H)
        // Try to open several joy devs:
        int joy_fd=-1;
        int nJoys = 0;

        do
        {
                if ( -1 != (joy_fd=open(format("/dev/input/js%i",nJoys).c_str(),O_RDONLY)) )
                {
                        nJoys++;
                        close(joy_fd);
                }
        } while (joy_fd!=-1);

        return nJoys;
#else
        // Apple:
        return 0;
#endif
        MRPT_END
}


/*---------------------------------------------------------------
  Gets joystick information.

  \return Returns true if successfull, false on error, for example, if joystick is not present.
 ---------------------------------------------------------------*/
bool CJoystick::getJoystickPosition(
        int     nJoy,
        float   &x,
        float   &y,
        float   &z,
        std::vector<bool>       &buttons,
        int *raw_x_pos,
        int     *raw_y_pos,
        int *raw_z_pos )
{
        MRPT_START
#ifdef MRPT_OS_WINDOWS
        JOYINFO         jinfo;

        int                     ID = JOYSTICKID1 + nJoy;

        // Get joy pos:
        if (JOYERR_NOERROR != joyGetPos( ID, &jinfo ) )
                return false;   // Error.

        // Output data:
        x = ( jinfo.wXpos - m_x_min ) / (float)( m_x_max-m_x_min );
        y = ( jinfo.wYpos - m_y_min ) / (float)( m_y_max-m_y_min );
        z = ( jinfo.wZpos - m_z_min ) / (float)( m_z_max-m_z_min );

        x = 2*x-1;
        y = 2*y-1;
        z = 2*z-1;

        buttons.resize(4);

        buttons[0] = 0 != (jinfo.wButtons & JOY_BUTTON1);
        buttons[1] = 0 != (jinfo.wButtons & JOY_BUTTON2);
        buttons[2] = 0 != (jinfo.wButtons & JOY_BUTTON3);
        buttons[3] = 0 != (jinfo.wButtons & JOY_BUTTON4);

        if (raw_x_pos) *raw_x_pos=jinfo.wXpos;
        if (raw_y_pos) *raw_y_pos=jinfo.wYpos;
        if (raw_z_pos) *raw_z_pos=jinfo.wZpos;

        return true;
#elif defined(MRPT_OS_LINUX) && defined(HAVE_LINUX_INPUT_H)
        // Already open?
        if ( m_joy_index == nJoy && m_joy_fd!=-1)
        {
                // Ok
        }
        else
        {
                // Close previous opened joy?
                if (m_joy_fd!=-1)
                        close(m_joy_fd);

                // Go, try open joystick:
                if ((m_joy_fd = open( format("/dev/input/js%i",nJoy).c_str() , O_RDONLY)) < 0)
                        return false;

                // Perfect!
                m_joy_index = nJoy;

                // Read in non-blocking way: **** Refer to sources of "jstest"!!!! ***
                fcntl(m_joy_fd, F_SETFL, O_NONBLOCK);
        }

        struct js_event js;

        while (read(m_joy_fd, &js, sizeof(struct js_event)) == sizeof(struct js_event))
        {
                // Button?
                if (js.type & JS_EVENT_BUTTON)
                {
                        // js.number: Button number
                        if (m_joystate_btns.size() < (size_t)js.number+1) m_joystate_btns.resize( js.number+1 );
                        m_joystate_btns[js.number] = js.value!=0;
                }

                // Axes?
                if (js.type & JS_EVENT_AXIS)
                {
                        //std::cout << "joy: event axis" << std::endl;
                        if (m_joystate_axes.size()<(size_t)js.number+1) m_joystate_axes.resize( js.number+1 );
                        m_joystate_axes[js.number] = js.value;
                }
        }

        if (errno != EAGAIN)
        {
                // Joystick disconnected?
                m_joy_fd = -1;
                m_joy_index = -1;
                return false;
        }


        // Fill out data:
        const size_t nAxis = m_joystate_axes.size();
        if (nAxis>=1)
        {
                x = -1+2*( m_joystate_axes[0] - m_x_min ) / (float)( m_x_max-m_x_min );
                if (raw_x_pos) *raw_x_pos = m_joystate_axes[0];
        }

        if (nAxis>=2)
        {
                y = -1+2*( m_joystate_axes[1] - m_y_min ) / (float)( m_y_max-m_y_min );
                if (raw_y_pos) *raw_y_pos = m_joystate_axes[1];
        }

        if (nAxis>=3)
        {
                z = -1+2*( m_joystate_axes[2] - m_z_min ) / (float)( m_z_max-m_z_min );
                if (raw_z_pos) *raw_z_pos = m_joystate_axes[2];
        }
        else
        {
                z=0;
        }

        buttons = m_joystate_btns;

        return true;
#else
        // Apple.
        return false;
#endif
        MRPT_END
}

/** Set the axis limit values, for computing a [-1,1] position index easily.
*   It seems that these values must been calibrated for each joystick model.
*
* \sa getJoystickPosition
*/
void  CJoystick::setLimits( int x_min ,int x_max , int y_min,int y_max ,int z_min,int z_max )
{
        m_x_max = x_max;
        m_x_min = x_min;

        m_y_max = y_max;
        m_y_min = y_min;

        m_z_max = z_max;
        m_z_min = z_min;
}