Cocos2dx 2.x Android gravity detection rotating screen, cocos2dx android

Cocos2dx 2.x Android gravity detection rotating screen, cocos2dx android

In the case of charging, when playing with a mobile phone, the screen usually needs a specific rotation direction.

The function is divided into two parts: one is to obtain the desired Angle Based on the mobile phone's gravity direction X, Y, and Z; the other is to set the screen rotation direction based on the rotation angle.

Listen to the value of the phone in the direction of X, Y, and Z to calculate the angle around a certain axis. X and Y are parallel to the mobile phone interface, while Z is perpendicular to the mobile phone interface.

This article takes the rotation around the Y axis as an example. If you want to rotate around the Z axis, you only need to swap Y and Z. In general, only these two cases are required.

The code is used for reference on the Internet.

package com.gamemaster.orientation;import android.hardware.Sensor;import android.hardware.SensorEvent;import android.hardware.SensorEventListener;import android.os.Handler;public class OrientationSensorListener implements SensorEventListener { private static final int _DATA_X = 0;     private static final int _DATA_Y = 1;     private static final int _DATA_Z = 2;          public static final int ORIENTATION_UNKNOWN = -1;          private Handler rotateHandler;               public OrientationSensorListener(Handler handler) {rotateHandler = handler;}public void onAccuracyChanged(Sensor arg0, int arg1) {// TODO Auto-generated method stub}public void onSensorChanged(SensorEvent event) {float[] values = event.values;        int orientation = ORIENTATION_UNKNOWN;        float X = -values[_DATA_X];        float Y = -values[_DATA_Y];        float Z = -values[_DATA_Z];          float magnitude = X*X + Z*Z;        // Don't trust the angle if the magnitude is small compared to the y value        if (magnitude * 4 >= Y*Y) {            float OneEightyOverPi = 57.29577957855f;            float angle = (float)Math.atan2(-Z, X) * OneEightyOverPi;            orientation = 90 - (int)Math.round(angle);            // normalize to 0 - 359 range            while (orientation >= 360) {                orientation -= 360;            }             while (orientation < 0) {                orientation += 360;            }        }                if (rotateHandler!=null) {rotateHandler.obtainMessage(888, orientation, 0).sendToTarget();}}}

The second part sets the screen direction based on the rotation angle.

package com.gamemaster.orientation;import android.app.Activity;import android.os.Handler;import android.os.Message;import android.util.Log;public class ChangeOrientationHandler extends Handler {private Activity activity;public ChangeOrientationHandler(Activity ac) {super();activity = ac;}@Overridepublic void handleMessage(Message msg) {  if (msg.what==888) {int orientation = msg.arg1;if (orientation>70&&orientation<135) {activity.setRequestedOrientation(8);}else if (orientation>135&&orientation<225){//activity.setRequestedOrientation(9); }else if (orientation>225&&orientation<290){activity.setRequestedOrientation(0);}else if ((orientation>315&&orientation<360)||(orientation>0&&orientation<45)){//activity.setRequestedOrientation(1); }}super.handleMessage(msg);        }}

Add

private Handler handler;    private OrientationSensorListener listener;private SensorManager sm;private Sensor sensor;

Add in the onCreate Function

handler = new ChangeOrientationHandler(this);     sm = (SensorManager)getSystemService(Context.SENSOR_SERVICE);    sensor = sm.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);           listener = new OrientationSensorListener(handler);    sm.registerListener(listener, sensor, SensorManager.SENSOR_DELAY_UI);

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