joystick.c

video linux conference

 *****************************************************************************/
static int Init( intf_thread_t * p_intf )
{
    char *psz_device;
    char *psz_parse;
    char *psz_eof;  /* end of field */

    psz_device = config_GetPsz( p_intf, "joystick-device");

    if( !psz_device ) /* strange... */
    {
        psz_device = strdup( DEFAULT_DEVICE );
    }

    p_intf->p_sys->i_fd = open( psz_device, O_RDONLY|O_NONBLOCK );

    if( p_intf->p_sys->i_fd == -1 )
    {
        msg_Warn( p_intf, "unable to open %s for reading: %s",
                          psz_device, strerror(errno) );
        return VLC_EGENERIC;
    }

    p_intf->p_sys->i_repeat = 1000 * config_GetInt( p_intf, "joystick-repeat");
    p_intf->p_sys->i_wait = 1000 * config_GetInt( p_intf, "joystick-wait");

    p_intf->p_sys->i_threshold = config_GetInt( p_intf, "motion-threshold" );
    if(p_intf->p_sys->i_threshold > 32767 || p_intf->p_sys->i_threshold < 0 )
        p_intf->p_sys->i_threshold = DEFAULT_THRESHOLD;

    p_intf->p_sys->i_maxseek = config_GetInt( p_intf, "joystick-max-seek" );

    psz_parse = config_GetPsz( p_intf, "joystick-mapping" ) ;

    if( ! psz_parse)
    {
        msg_Warn (p_intf,"invalid mapping. aborting" );
        return VLC_EGENERIC;
    }

    if( !strlen( psz_parse ) )
    {
        msg_Warn( p_intf, "invalid mapping, aborting" );
        return VLC_EGENERIC;
    }

    p_intf->p_sys->axes[0].pf_actup  = AXIS_0_UP_ACTION;
    p_intf->p_sys->axes[0].pf_actdown  = AXIS_0_DOWN_ACTION;
    p_intf->p_sys->axes[1].pf_actup  = AXIS_1_UP_ACTION;
    p_intf->p_sys->axes[1].pf_actdown  = AXIS_1_DOWN_ACTION;

    p_intf->p_sys->buttons[0].pf_actdown = BUTTON_1_PRESS_ACTION;
    p_intf->p_sys->buttons[0].pf_actup   = BUTTON_1_RELEASE_ACTION;
    p_intf->p_sys->buttons[1].pf_actdown = BUTTON_2_PRESS_ACTION;
    p_intf->p_sys->buttons[1].pf_actup   = BUTTON_2_RELEASE_ACTION;

/* Macro to parse the command line */
#define PARSE(name,function)                                                  \
    if(!strncmp( psz_parse, name, strlen( name ) ) )                          \
    {                                                                         \
        psz_parse += strlen( name );                                          \
        psz_eof = strchr( psz_parse, ',' );                                   \
        if( !psz_eof)                                                         \
            psz_eof = strchr( psz_parse, '}' );                               \
        if( !psz_eof)                                                         \
            psz_eof = psz_parse + strlen(psz_parse);                          \
        if( psz_eof )                                                         \
        {                                                                     \
            *psz_eof = '\0' ;                                                 \
        }                                                                     \
        msg_Dbg(p_intf,"%s -> %s", name,psz_parse) ;                          \
        if(!strcasecmp( psz_parse, "play" ) ) function = Play;                \
        if(!strcasecmp( psz_parse, "next" ) ) function = Next;                \
        if(!strcasecmp( psz_parse, "prev" ) ) function = Prev;                \
        if(!strcasecmp( psz_parse, "fullscreen" ) ) function = Fullscreen;    \
        if(!strcasecmp( psz_parse, "forward" ) ) function = Forward;          \
        if(!strcasecmp( psz_parse, "back" ) ) function = Back;                \
        psz_parse = psz_eof;                                                  \
        psz_parse ++;                                                         \
        continue;                                                             \
    }                                                                         \

    for( ; *psz_parse ; psz_parse++ )
    {
        PARSE("axis-0-up=",   p_intf->p_sys->axes[0].pf_actup );
        PARSE("axis-0-down=", p_intf->p_sys->axes[0].pf_actdown );
        PARSE("axis-1-up=",   p_intf->p_sys->axes[1].pf_actup );
        PARSE("axis-1-down=", p_intf->p_sys->axes[1].pf_actdown );

        PARSE("butt-1-up=",   p_intf->p_sys->buttons[0].pf_actup );
        PARSE("butt-1-down=", p_intf->p_sys->buttons[0].pf_actdown );
        PARSE("butt-2-up=",   p_intf->p_sys->buttons[1].pf_actup );
        PARSE("butt-2-down=", p_intf->p_sys->buttons[1].pf_actdown );
    }

    p_intf->p_sys->axes[0].b_trigered = VLC_FALSE;
    p_intf->p_sys->axes[0].l_time = 0;

    p_intf->p_sys->axes[1].b_trigered = VLC_FALSE;
    p_intf->p_sys->axes[1].l_time = 0;

    return VLC_SUCCESS;
}

/*****************************************************************************
 * handle_event : parse a joystick event and takes the appropriate action    *
 *****************************************************************************/
static int handle_event ( intf_thread_t *p_intf, struct js_event event)
{
    unsigned int i_axis;

    if( event.type == JS_EVENT_AXIS )
    {
        /* Third axis is supposed to behave in a different way: it is a
         * throttle, and will set a value, without triggering anything */
        if( event.number == 2 &&
            /* Try to avoid Parkinson joysticks */
            abs(event.value - p_intf->p_sys->axes[2].i_value) > 200 )
        {
            p_intf->p_sys->axes[2].i_value = event.value;
            msg_Dbg( p_intf, "updating volume" );
            /* This way, the volume is between 0 and 1024 */
            aout_VolumeSet( p_intf, (32767-event.value)/64 );
            return 0;
        }

        p_intf->p_sys->axes[event.number].b_dowork = VLC_FALSE;
        p_intf->p_sys->axes[event.number].i_value  = event.value;

        if( abs(event.value) > p_intf->p_sys->i_threshold &&
             p_intf->p_sys->axes[event.number].b_trigered == VLC_FALSE )
        {
            /* The axis entered the trigger zone. Start the event */
            p_intf->p_sys->axes[event.number].b_trigered = VLC_TRUE;
            p_intf->p_sys->axes[event.number].b_dowork   = VLC_TRUE;
            p_intf->p_sys->axes[event.number].l_time     = mdate();
        }
        else if( abs(event.value) > p_intf->p_sys->i_threshold &&
                 p_intf->p_sys->axes[event.number].b_trigered == VLC_TRUE )
        {
            /* The axis moved but remained in the trigger zone
             * Do nothing at this time */
        }
        else if( abs(event.value) < p_intf->p_sys->i_threshold )
        {
            /* The axis is not in the trigger zone */
            p_intf->p_sys->axes[event.number].b_trigered = VLC_FALSE;
        }

        /* Special for seeking */
        p_intf->p_sys->f_seconds = 1 +
            (abs(event.value) - p_intf->p_sys->i_threshold) *
            (p_intf->p_sys->i_maxseek - 1 ) /
            (32767 - p_intf->p_sys->i_threshold);


        /* Handle the first two axes. */
        for(i_axis = 0; i_axis <= 1; i_axis ++)
        {
            if(p_intf->p_sys->axes[i_axis].b_dowork == VLC_TRUE)
            {
                if( p_intf->p_sys->axes[i_axis].i_value
                              > p_intf->p_sys->i_threshold )
                {
                    msg_Dbg(p_intf,"up for axis %i\n",i_axis);
                    p_intf->p_sys->axes[i_axis].pf_actup(p_intf);
                }
                else if( p_intf->p_sys->axes[i_axis].i_value
                                < -p_intf->p_sys->i_threshold )
                {
                    msg_Dbg(p_intf,"down for axis %i\n",i_axis);
                    p_intf->p_sys->axes[i_axis].pf_actdown(p_intf);
                }

            }
        }
    }
    else if( event.type == JS_EVENT_BUTTON )
    {
        msg_Dbg( p_intf, "button %i %s", event.number,
                         event.value ? "pressed" : "released" );
        if( event.number > 1 )
            return 0; /* Only trigger 2 buttons */

        if( event.value == 1 ) /* Button pressed */
        {
            if( p_intf->p_sys->buttons[event.number].pf_actdown )
                p_intf->p_sys->buttons[event.number].pf_actdown( p_intf );
        }
        else /* Button released */
        {
            if( p_intf->p_sys->buttons[event.number].pf_actup )
                p_intf->p_sys->buttons[event.number].pf_actup( p_intf );
        }
    }
    return 0;
}

/****************************************************************************
 * The actions
 ****************************************************************************/

/* Go to next item in the playlist */
static int Next( intf_thread_t *p_intf )
{
    playlist_t *p_playlist;

    p_playlist = vlc_object_find( p_intf, VLC_OBJECT_PLAYLIST, FIND_ANYWHERE );
    if( p_playlist == NULL )
    {
        return VLC_ENOOBJ;
    }

    playlist_Next( p_playlist );
    vlc_object_release( p_playlist );
    return VLC_SUCCESS;
}

/* Go to previous item in the playlist */
static int Prev( intf_thread_t *p_intf )
{
    playlist_t *p_playlist;

    p_playlist = vlc_object_find( p_intf, VLC_OBJECT_PLAYLIST, FIND_ANYWHERE );
    if( p_playlist == NULL )
    {
        return VLC_ENOOBJ;
    }

    playlist_Prev( p_playlist );
    vlc_object_release( p_playlist );
    return VLC_SUCCESS;
}

/* Seek forward */
static int Forward( intf_thread_t *p_intf )
{
    if( p_intf->p_sys->p_input )
    {
        msg_Dbg( p_intf,"seeking %f seconds",p_intf->p_sys->f_seconds );
        var_SetTime( p_intf->p_sys->p_input, "time-offset",
                     (int64_t)p_intf->p_sys->f_seconds * I64C(1000000) );
        return VLC_SUCCESS;
    }

    return VLC_ENOOBJ;
}

/* Seek backwards */
static int Back( intf_thread_t *p_intf )
{
    if( p_intf->p_sys->p_input )
    {
        msg_Dbg( p_intf,"seeking -%f seconds", p_intf->p_sys->f_seconds );

        var_SetTime( p_intf->p_sys->p_input, "time-offset",
                     -(int64_t)p_intf->p_sys->f_seconds * I64C(1000000) );
        return VLC_SUCCESS;
    }

    return VLC_ENOOBJ;
}

/* Toggle Play/Pause */
static int Play( intf_thread_t *p_intf )
{
    if( p_intf->p_sys->p_input )
    {
        var_SetInteger( p_intf->p_sys->p_input, "state", PAUSE_S );
        return VLC_SUCCESS;
    }

    return VLC_ENOOBJ;
}

/* Toggle fullscreen mode */
static int Fullscreen( intf_thread_t *p_intf )
{
    vout_thread_t * p_vout;

    p_vout = vlc_object_find(p_intf, VLC_OBJECT_VOUT, FIND_ANYWHERE );
    if( p_vout )
    {
        p_vout->i_changes |= VOUT_FULLSCREEN_CHANGE;
        vlc_object_release(p_vout);
    }
    return VLC_SUCCESS;
}

/* dummy event. Use it if you don't wan't anything to happen */
static int dummy( intf_thread_t *p_intf )
{
    return VLC_SUCCESS;
}