[android-developers] manager sensor data in Android

Hi, I am going some project on the sensors on Android. I didn't understand coordination transform mechanism inside Android. 1. I know AXIS_X,AXIS_Y,AXIS_Z. but can anyone tell me what exactly the three axis (AXIS_MINUS_X, AXIS_MINUS_Y, AXIS_MINUS_Z) mean? 2. what do the rotation matrix and

[android-developers] how to use getRotationMatrix to 3D Transformations

hi I am a newbie. currently I am trying to make a program using android sensors . I hope to get accelerations of 3 axis in earth coordinate system. It is easy to get 3 accelerations and orientation angles in phone coordinate system. So I made 3d transformation using equations as