问题描述
可能的复制：Android当手机倾斜 getOrientation方位被污染
Possible duplicate : Android getOrientation Azimuth gets polluted when phone is tilted
我是新android开发，我试图让面对用户。
I am new to android development and I try to get the user facing.
在网络上搜索后我pretty知道我需要使用 remapCoordinateSystem ，Android文档说，这是很好的使用增强现实应用程序。
After searching on the web I am pretty sure I need to use remapCoordinateSystem, android documentation say it is good to use for an augmented reality app.
我尝试使用一些现有的code，以确保这是一个很好的方式。
I try to use some existing code to be sure that is a good way.
（最后，我想创建一个增强现实应用程序）
(Finally I want to create an augmented reality application)
以下code应该返回度面对用户：
The following code should return the user facing in degree :
Sensor sensor = event.sensor;
if (sensor.getType() == Sensor.TYPE_ACCELEROMETER) {
gravity = event.values.clone();
}else if (sensor.getType() == Sensor.TYPE_MAGNETIC_FIELD) {
geomagnetic = event.values.clone();
}
if (gravity != null && geomagnetic != null){
_rM = SensorManager.getRotationMatrix (R, null, gravity, geomagnetic);
if(_rM){
int mScreenRotation = activity.getWindowManager().getDefaultDisplay().getRotation(); // get user orientation mode
switch (mScreenRotation) { // Handle device rotation (landscape, portrait)
case Surface.ROTATION_0:
axisX = SensorManager.AXIS_X;
axisY = SensorManager.AXIS_Y;
break;
case Surface.ROTATION_90:
axisX = SensorManager.AXIS_Y;
axisY = SensorManager.AXIS_MINUS_X;
break;
case Surface.ROTATION_180: // not handled by my phone so I can't test
axisX = SensorManager.AXIS_MINUS_X;
axisY = SensorManager.AXIS_MINUS_Y;
break;
case Surface.ROTATION_270:
axisX = SensorManager.AXIS_MINUS_Y;
axisY = SensorManager.AXIS_X;
break;
default:
break;
}
SensorManager.remapCoordinateSystem (R, axisX, axisY, outR);
SensorManager.getOrientation (outR, gO);
}
}
userFacing = (float) Math.toDegrees(gO[0]); // Radian to degree
if(userFacing<0) { userFacing+=360; } // -180;180 to 0;360
return userFacing;
其实我能得到一个准确的指南针当手机朝下，但是当我尝试移动电话（作为一个用户会做），结果是非常不准确的：当我倾斜装置，方向可移动40°...
Actually I am able to get an accurate compass when the phone is facing down, but when I try to move the phone (as a user would do), the results are very inaccurate : when i tilt the device, direction can move of 40°...
我看到此链接：http://stackoverflow.com/questions/17979238/android-getorientation-azimuth-gets-polluted-when-phone-is-tilted
但是，如果我留倾斜，结果是不准确的再次（这是一个平均水平，所以这是正常的！）
我需要指南针随时随地工作...
But if i stay tilted, the results are inaccurate again (it's an average, so it's normal!)And i need the compass working anytime...
我想我会使用 TYPE_GYROSCOPE ，但不是所有的设备都有一个陀螺仪时下，所以我需要的所有其他设备另一种解决方案！
I think I will use TYPE_GYROSCOPE, but not all devices have a gyroscope nowadays so i need another solution for all the other devices !
希望你能理解我的问题，我的英语不好对不起！ （我是法国人）
Hope you can understand my problem, and sorry for my bad english! (I'm French)
好了，所以适应iOS上的应用程序之后，我决定进去看看android的方法是一样好，我虽然。一个月前，我贴的解决方案，这是真的错了。我做了关于 remapCoordinateSystem 一个巨大的错误：我用 AXIS_X 和 AXIS_Y 让我矩阵的计算，我试图纠正不同的价值观我的价值观。作为@HoanNguyen建议，我们只需要使用 AXIS_X 和 AXIS_Z 和android处理剩下的。
Ok so after adapting the application on iOS, I decided to check if the android methods were as good as I though. A month ago, I posted a solution and it was really wrong. I made a huge mistake on remapCoordinateSystem : I used AXIS_X and AXIS_Y to get my matrice and I tried to correct my values with different values. As @HoanNguyen suggested, we just have to use AXIS_X and AXIS_Zand android handle the rest.
因此，这里是最后的code。很多更短，更容易：
So here is the final code. Lot more shorter and easier:
if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER) {
gravity = lowPass(event.values.clone(), gravity);
}
else if (event.sensor.getType() == Sensor.TYPE_MAGNETIC_FIELD) {
geomagnetic = lowPass(event.values.clone(), geomagnetic);
}
if (geomagnetic != null && gravity != null) {
if (SensorManager.getRotationMatrix (R_in, null, gravity, geomagnetic)) {
SensorManager.remapCoordinateSystem (R_in, SensorManager.AXIS_X, SensorManager.AXIS_Z, R_out);
SensorManager.getOrientation (R_out, gO);
}
}
和得到磁北，你只需要使用 GO [0] 如标题= GO [0]; 的（注意，返回的值是弧度）的
And to get magnetic north, you just have to use gO[0] like heading = gO[0]; (Caution, the returned values are in radians)
希望它可以在这里有人！
推荐答案
您都code，你找到了解决办法是通过手机面临着你是指设备z坐标的相反方向错的，如果。增强现实，你只需要调用
Both your code and the solution you found are wrong if by "phone facing" you means the opposite direction of the device z-coordinate. For augmented reality, you just call
remapCoordinateSystem(inR, AXIS_X, AXIS_Z, outR);
设备方向的独立。然后在调用getOrientation（）中的方位给出关于磁北面向电话的方向。
independent of the device orientation. Then the azimuth in the call to getOrientation() gives the direction of the phone facing with respect to Magnetic North.
这2个呼叫等于器件z坐标到世界的XY平面的投影座标，然后计算所得到的矢量的方向。
These 2 calls amount to projection of the device z-coordinate to the XY plane of the world coordinates and then calculate the direction of the resulting vector.
这篇关于如何获得手机走向增强现实？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！