File content as of revision 5:48ba213dfbb3:

#include "Joystick.h"

int mapInto(int x, int in_min, int in_max, int out_min, int out_max)
{
    return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
}

int constrain(int x, int x_min, int x_max)
{
    return x >= x_min && x <= x_max ? x : (x < x_min ? x_min : x_max);
}

void Joystick::process(void)
{
    JoystickValue newValue(_xIn.read_u16(), _yIn.read_u16());
    if (!_calibrated) //Calibrating
    {
        _center.x = (_center.x + newValue.x) / 2;
        _center.y = (_center.y + newValue.y) / 2;
        if (++_calibrationCounter >= JOYSTICK_CALIBRATION_CYCLES)
		{
			_calibrated = true;
		}
    }
    else if (!_locked) //Normal process if not locked
    {
        if (newValue.x < _center.x - JOYSTICK_CENTER_DEADZONE)
        {
            newValue.x = newValue.x - (_center.x - JOYSTICK_CENTER_DEADZONE);
        }
        else if (newValue.x > _center.x + JOYSTICK_CENTER_DEADZONE)
        {
            newValue.x = newValue.x - (_center.x + JOYSTICK_CENTER_DEADZONE);
        }
        else
        {
            newValue.x = 0;
        }
        if (newValue.y < _center.y - JOYSTICK_CENTER_DEADZONE)
        {
            newValue.y = newValue.y - (_center.y - JOYSTICK_CENTER_DEADZONE);
        }
        else if (newValue.y > _center.y + JOYSTICK_CENTER_DEADZONE)
        {
            newValue.y = newValue.y - (_center.y + JOYSTICK_CENTER_DEADZONE);
        }
        else
        {
            newValue.y = 0;
        }
        newValue.x = constrain(mapInto(newValue.x, -(JOYSTICK_ADC_MAX - JOYSTICK_CENTER_DEADZONE * 2) / 2, (JOYSTICK_ADC_MAX - JOYSTICK_CENTER_DEADZONE * 2) / 2, -_range, _range), -_range, _range);
        newValue.y = constrain(mapInto(newValue.y, -(JOYSTICK_ADC_MAX - JOYSTICK_CENTER_DEADZONE * 2) / 2, (JOYSTICK_ADC_MAX - JOYSTICK_CENTER_DEADZONE * 2) / 2, -_range, _range), -_range, _range);
        if (_swapXY)
        {
            int t = newValue.x;
            newValue.x = newValue.y;
            newValue.y = t;
        }
        JoystickValue joyPrev(_joyValue);
        _joyValue.x = _flipX ? -1 * newValue.x : newValue.x;
        _joyValue.y = _flipY ? -1 * newValue.y : newValue.y;
        if (_onChange != NULL && (_delta == 0 || abs(_joyValue.x - joyPrev.x) >= _delta || abs(_joyValue.y - joyPrev.y) >= _delta))
        {
            _onChange(_joyValue, joyPrev);
        }
    }
}