GameController.java

//Created by Matthias Mueller - Intel Intelligent Systems Lab - 2020

package org.openbot.env;

import android.view.InputDevice;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.widget.Toast;

import org.openbot.CameraActivity;
import org.openbot.CameraActivity.ControlSignal;
import org.openbot.CameraActivity.DriveMode;


public class GameController {
  private float left = 0;
  private float right = 0;
  private DriveMode driveMode;

  public GameController(DriveMode driveMode) {
    this.driveMode = driveMode;
  }

  public void setDriveMode(DriveMode mode) {
      driveMode = mode;
  }

  public DriveMode getDriveMode() {return driveMode;}

  private static float getCenteredAxis(MotionEvent event,
                                       InputDevice device,
                                       int axis,
                                       int historyPos) {

    final InputDevice.MotionRange range =
            device.getMotionRange(axis, event.getSource());

    // A joystick at rest does not always report an absolute position of
    // (0,0). Use the getFlat() method to determine the range of values
    // bounding the joystick axis center.
    if (range != null) {
      final float flat = range.getFlat();
      final float value =
              historyPos < 0 ? event.getAxisValue(axis):
                      event.getHistoricalAxisValue(axis, historyPos);

      // Ignore axis values that are within the 'flat' region of the
      // joystick axis center.
      if (Math.abs(value) > flat) {
        return value;
      }
    }
    return 0;
  }

  public void processButtonInput(KeyEvent event){
    switch (event.getKeyCode()) {
      case KeyEvent.KEYCODE_BUTTON_A:
        Toast.makeText(CameraActivity.getContext(),"A recognized", Toast.LENGTH_SHORT).show();
        return;
      case KeyEvent.KEYCODE_BUTTON_B:
        Toast.makeText(CameraActivity.getContext(),"B recognized", Toast.LENGTH_SHORT).show();
        return;
      case KeyEvent.KEYCODE_BUTTON_Y:
        Toast.makeText(CameraActivity.getContext(),"Y recognized", Toast.LENGTH_SHORT).show();
        return;
      case KeyEvent.KEYCODE_BUTTON_X:
        Toast.makeText(CameraActivity.getContext(),"X recognized", Toast.LENGTH_SHORT).show();
        return;
      case KeyEvent.KEYCODE_BUTTON_L1:
        Toast.makeText(CameraActivity.getContext(),"L1 recognized", Toast.LENGTH_SHORT).show();
        return;
      case KeyEvent.KEYCODE_BUTTON_R1:
        Toast.makeText(CameraActivity.getContext(),"R1 recognized", Toast.LENGTH_SHORT).show();
        return;
      default:
        Toast.makeText(CameraActivity.getContext(),"Key " + event.getKeyCode() + " not recognized", Toast.LENGTH_SHORT).show();
        return;
    }
  }

  public ControlSignal processJoystickInput(MotionEvent event, int historyPos) {

    InputDevice inputDevice = event.getDevice();
    switch (driveMode) {
      case DUAL:
        float y = getCenteredAxis(event, inputDevice,
                MotionEvent.AXIS_Y, historyPos);
        float rz = getCenteredAxis(event, inputDevice,
                MotionEvent.AXIS_RZ, historyPos);
        left = -y;
        right = -rz;
        break;

      case GAME:
        float r_trigger = getCenteredAxis(event, inputDevice,
                MotionEvent.AXIS_GAS, historyPos);
        if (r_trigger == 0) {
          r_trigger = getCenteredAxis(event, inputDevice,
                  MotionEvent.AXIS_RTRIGGER, historyPos);
        }

        float l_trigger = getCenteredAxis(event, inputDevice,
                MotionEvent.AXIS_BRAKE, historyPos);
        if (l_trigger == 0) {
          l_trigger = getCenteredAxis(event, inputDevice,
                  MotionEvent.AXIS_LTRIGGER, historyPos);
        }

        // Calculate the steering magnitude by
        // using the input value from one of these physical controls:
        // the left control stick, hat axis, or the right control stick.
        float steering_offset = getCenteredAxis(event, inputDevice,
                MotionEvent.AXIS_X, historyPos);
        if (steering_offset == 0) {
          steering_offset = getCenteredAxis(event, inputDevice,
                  MotionEvent.AXIS_HAT_X, historyPos);
        }
        if (steering_offset == 0) {
          steering_offset = getCenteredAxis(event, inputDevice,
                  MotionEvent.AXIS_Z, historyPos);
        }

        left = r_trigger - l_trigger;
        right = r_trigger - l_trigger;

        if (steering_offset > 0) {
          if (right >= 0) right -= steering_offset;
          else right += steering_offset;
        }
        if (steering_offset < 0)
        {
          if (left >= 0) left += steering_offset;
          else left -= steering_offset;
        }
        break;

      case JOYSTICK:
        // Calculate the vertical distance to move by
        // using the input value from one of these physical controls:
        // the left control stick, hat switch, or the right control stick.
        float y_axis = getCenteredAxis(event, inputDevice,
                MotionEvent.AXIS_Y, historyPos);
        if (y_axis == 0) {
          y_axis = getCenteredAxis(event, inputDevice,
                  MotionEvent.AXIS_HAT_Y, historyPos);
        }
        if (y_axis == 0) {
          y_axis = getCenteredAxis(event, inputDevice,
                  MotionEvent.AXIS_RZ, historyPos);
        }

        // Calculate the horizontal distance to move by
        // using the input value from one of these physical controls:
        // the left control stick, hat axis, or the right control stick.
        float x_axis = getCenteredAxis(event, inputDevice,
                MotionEvent.AXIS_X, historyPos);
        if (x_axis == 0) {
          x_axis = getCenteredAxis(event, inputDevice,
                  MotionEvent.AXIS_HAT_X, historyPos);
        }
        if (x_axis == 0) {
          x_axis = getCenteredAxis(event, inputDevice,
                  MotionEvent.AXIS_Z, historyPos);
        }

        left = -y_axis;
        right = -y_axis;

        if (x_axis > 0) {
          if (right >= 0) right -= x_axis;
          else right += x_axis;
        }
        if (x_axis < 0)
        {
          if (left >= 0) left += x_axis;
          else left -= x_axis;
        }

        break;

      default:
        left = 0;
        right = 0;
        break;
    }

    left *= 255;
    right *= 255;

    return new ControlSignal((int)left,(int)right);

  }

}