如何结合opengl使用onsensorchanged传感器数据

(编辑:我在 augmented reality framework 现在还考虑到陀螺仪,这使它更加稳定: DroidAR framework )

我已经编写了一个测试套件来了解如何从你得到的数据中计算旋转角度 SensorEventListener.onSensorChanged() . 我真的希望你能完成我的解决方案,帮助像我一样有同样问题的人。这是密码,我想你看完后会明白的。

可以随意更改它,主要思想是实现几种方法,将方向角发送到opengl视图或任何其他需要它的目标。

方法1到4正在工作,它们直接将rotationmatrix发送到opengl视图。

方法6现在也可以工作了,但是我无法解释为什么要做y x z的旋转。

所有其他的方法都不起作用,我希望有人知道如何使它们起作用。我认为最好的方法是方法5,如果它能起作用的话,因为它是最容易理解的,但我不确定它有多有效。完整的代码没有经过优化,所以我建议不要像在项目中那样使用它。

这里是:

/**
 * This class provides a basic demonstration of how to use the
 * {@link android.hardware.SensorManager SensorManager} API to draw a 3D
 * compass.
 */
public class SensorToOpenGlTests extends Activity implements Renderer,
  SensorEventListener {

 private static final boolean TRY_TRANSPOSED_VERSION = false;

 /*
  * MODUS overview:
  * 
  * 1 - unbufferd data directly transfaired from the rotation matrix to the
  * modelview matrix
  * 
  * 2 - buffered version of 1 where both acceleration and magnetometer are
  * buffered
  * 
  * 3 - buffered version of 1 where only magnetometer is buffered
  * 
  * 4 - buffered version of 1 where only acceleration is buffered
  * 
  * 5 - uses the orientation sensor and sets the angles how to rotate the
  * camera with glrotate()
  * 
  * 6 - uses the rotation matrix to calculate the angles
  * 
  * 7 to 12 - every possibility how the rotationMatrix could be constructed
  * in SensorManager.getRotationMatrix (see
  * http://www.songho.ca/opengl/gl_anglestoaxes.html#anglestoaxes for all
  * possibilities)
  */

 private static int MODUS = 2;

 private GLSurfaceView openglView;
 private FloatBuffer vertexBuffer;
 private ByteBuffer indexBuffer;
 private FloatBuffer colorBuffer;

 private SensorManager mSensorManager;
 private float[] rotationMatrix = new float[16];
 private float[] accelGData = new float[3];
 private float[] bufferedAccelGData = new float[3];
 private float[] magnetData = new float[3];
 private float[] bufferedMagnetData = new float[3];
 private float[] orientationData = new float[3];

 // private float[] mI = new float[16];

 private float[] resultingAngles = new float[3];

 private int mCount;

 final static float rad2deg = (float) (180.0f / Math.PI);

 private boolean landscape;

 public SensorToOpenGlTests() {
 }

 /** Called with the activity is first created. */
 @Override
 public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);

  mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
  openglView = new GLSurfaceView(this);
  openglView.setRenderer(this);
  setContentView(openglView);
 }

 @Override
 protected void onResume() {
  // Ideally a game should implement onResume() and onPause()
  // to take appropriate action when the activity looses focus
  super.onResume();
  openglView.onResume();

  if (((WindowManager) getSystemService(WINDOW_SERVICE))
    .getDefaultDisplay().getOrientation() == 1) {
   landscape = true;
  } else {
   landscape = false;
  }

  mSensorManager.registerListener(this, mSensorManager
    .getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
    SensorManager.SENSOR_DELAY_GAME);
  mSensorManager.registerListener(this, mSensorManager
    .getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD),
    SensorManager.SENSOR_DELAY_GAME);
  mSensorManager.registerListener(this, mSensorManager
    .getDefaultSensor(Sensor.TYPE_ORIENTATION),
    SensorManager.SENSOR_DELAY_GAME);
 }

 @Override
 protected void onPause() {
  // Ideally a game should implement onResume() and onPause()
  // to take appropriate action when the activity looses focus
  super.onPause();
  openglView.onPause();
  mSensorManager.unregisterListener(this);
 }

 public int[] getConfigSpec() {
  // We want a depth buffer, don't care about the
  // details of the color buffer.
  int[] configSpec = { EGL10.EGL_DEPTH_SIZE, 16, EGL10.EGL_NONE };
  return configSpec;
 }

 public void onDrawFrame(GL10 gl) {

  // clear screen and color buffer:
  gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
  // set target matrix to modelview matrix:
  gl.glMatrixMode(GL10.GL_MODELVIEW);
  // init modelview matrix:
  gl.glLoadIdentity();
  // move camera away a little bit:

  if ((MODUS == 1) || (MODUS == 2) || (MODUS == 3) || (MODUS == 4)) {

   if (landscape) {
    // in landscape mode first remap the rotationMatrix before using
    // it with glMultMatrixf:
    float[] result = new float[16];
    SensorManager.remapCoordinateSystem(rotationMatrix,
      SensorManager.AXIS_Y, SensorManager.AXIS_MINUS_X,
      result);
    gl.glMultMatrixf(result, 0);
   } else {
    gl.glMultMatrixf(rotationMatrix, 0);
   }
  } else {
   //in all other modes do the rotation by hand
   //the order y x z is important!
   gl.glRotatef(resultingAngles[2], 0, 1, 0);
   gl.glRotatef(resultingAngles[1], 1, 0, 0);
   gl.glRotatef(resultingAngles[0], 0, 0, 1);
  }

  //move the axis to simulate augmented behaviour:
  gl.glTranslatef(0, 2, 0);

  // draw the 3 axis on the screen:
  gl.glVertexPointer(3, GL_FLOAT, 0, vertexBuffer);
  gl.glColorPointer(4, GL_FLOAT, 0, colorBuffer);
  gl.glDrawElements(GL_LINES, 6, GL_UNSIGNED_BYTE, indexBuffer);
 }

 public void onSurfaceChanged(GL10 gl, int width, int height) {
  gl.glViewport(0, 0, width, height);
  float r = (float) width / height;
  gl.glMatrixMode(GL10.GL_PROJECTION);
  gl.glLoadIdentity();
  gl.glFrustumf(-r, r, -1, 1, 1, 10);
 }

 public void onSurfaceCreated(GL10 gl, EGLConfig config) {
  gl.glDisable(GL10.GL_DITHER);
  gl.glClearColor(1, 1, 1, 1);
  gl.glEnable(GL10.GL_CULL_FACE);
  gl.glShadeModel(GL10.GL_SMOOTH);
  gl.glEnable(GL10.GL_DEPTH_TEST);

  gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
  gl.glEnableClientState(GL10.GL_COLOR_ARRAY);

  // load the 3 axis and there colors:
  float vertices[] = { 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1 };
  float colors[] = { 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1 };
  byte indices[] = { 0, 1, 0, 2, 0, 3 };

  ByteBuffer vbb;
  vbb = ByteBuffer.allocateDirect(vertices.length * 4);
  vbb.order(ByteOrder.nativeOrder());
  vertexBuffer = vbb.asFloatBuffer();
  vertexBuffer.put(vertices);
  vertexBuffer.position(0);

  vbb = ByteBuffer.allocateDirect(colors.length * 4);
  vbb.order(ByteOrder.nativeOrder());
  colorBuffer = vbb.asFloatBuffer();
  colorBuffer.put(colors);
  colorBuffer.position(0);

  indexBuffer = ByteBuffer.allocateDirect(indices.length);
  indexBuffer.put(indices);
  indexBuffer.position(0);
 }

 public void onAccuracyChanged(Sensor sensor, int accuracy) {
 }

 public void onSensorChanged(SensorEvent event) {

  // load the new values:
  loadNewSensorData(event);

  if (MODUS == 1) {
   SensorManager.getRotationMatrix(rotationMatrix, null, accelGData,
     magnetData);
  }

  if (MODUS == 2) {
   rootMeanSquareBuffer(bufferedAccelGData, accelGData);
   rootMeanSquareBuffer(bufferedMagnetData, magnetData);
   SensorManager.getRotationMatrix(rotationMatrix, null,
     bufferedAccelGData, bufferedMagnetData);
  }

  if (MODUS == 3) {
   rootMeanSquareBuffer(bufferedMagnetData, magnetData);
   SensorManager.getRotationMatrix(rotationMatrix, null, accelGData,
     bufferedMagnetData);
  }

  if (MODUS == 4) {
   rootMeanSquareBuffer(bufferedAccelGData, accelGData);
   SensorManager.getRotationMatrix(rotationMatrix, null,
     bufferedAccelGData, magnetData);
  }

  if (MODUS == 5) {
   // this mode uses the sensor data recieved from the orientation
   // sensor
   resultingAngles = orientationData.clone();
   if ((-90 > resultingAngles[1]) || (resultingAngles[1] > 90)) {
    resultingAngles[1] = orientationData[0];
    resultingAngles[2] = orientationData[1];
    resultingAngles[0] = orientationData[2];
   }
  }

  if (MODUS == 6) {
   SensorManager.getRotationMatrix(rotationMatrix, null, accelGData,
     magnetData);
   final float[] anglesInRadians = new float[3];
   SensorManager.getOrientation(rotationMatrix, anglesInRadians);
   //TODO check for landscape mode
   resultingAngles[0] = anglesInRadians[0] * rad2deg;
   resultingAngles[1] = anglesInRadians[1] * rad2deg;
   resultingAngles[2] = anglesInRadians[2] * -rad2deg;
  }

  if (MODUS == 7) {
   SensorManager.getRotationMatrix(rotationMatrix, null, accelGData,
     magnetData);

   rotationMatrix = transpose(rotationMatrix);
   /*
    * this assumes that the rotation matrices are multiplied in x y z
    * order Rx*Ry*Rz
    */

   resultingAngles[2] = (float) (Math.asin(rotationMatrix[2]));
   final float cosB = (float) Math.cos(resultingAngles[2]);
   resultingAngles[2] = resultingAngles[2] * rad2deg;
   resultingAngles[0] = -(float) (Math.acos(rotationMatrix[0] / cosB))
     * rad2deg;
   resultingAngles[1] = (float) (Math.acos(rotationMatrix[10] / cosB))
     * rad2deg;
  }

  if (MODUS == 8) {
   SensorManager.getRotationMatrix(rotationMatrix, null, accelGData,
     magnetData);
   rotationMatrix = transpose(rotationMatrix);
   /*
    * this assumes that the rotation matrices are multiplied in z y x
    */

   resultingAngles[2] = (float) (Math.asin(-rotationMatrix[8]));
   final float cosB = (float) Math.cos(resultingAngles[2]);
   resultingAngles[2] = resultingAngles[2] * rad2deg;
   resultingAngles[1] = (float) (Math.acos(rotationMatrix[9] / cosB))
     * rad2deg;
   resultingAngles[0] = (float) (Math.asin(rotationMatrix[4] / cosB))
     * rad2deg;
  }

  if (MODUS == 9) {
   SensorManager.getRotationMatrix(rotationMatrix, null, accelGData,
     magnetData);
   rotationMatrix = transpose(rotationMatrix);
   /*
    * this assumes that the rotation matrices are multiplied in z x y
    * 
    * note z axis looks good at this one
    */

   resultingAngles[1] = (float) (Math.asin(rotationMatrix[9]));
   final float minusCosA = -(float) Math.cos(resultingAngles[1]);
   resultingAngles[1] = resultingAngles[1] * rad2deg;
   resultingAngles[2] = (float) (Math.asin(rotationMatrix[8]
     / minusCosA))
     * rad2deg;
   resultingAngles[0] = (float) (Math.asin(rotationMatrix[1]
     / minusCosA))
     * rad2deg;
  }

  if (MODUS == 10) {
   SensorManager.getRotationMatrix(rotationMatrix, null, accelGData,
     magnetData);
   rotationMatrix = transpose(rotationMatrix);
   /*
    * this assumes that the rotation matrices are multiplied in y x z
    */

   resultingAngles[1] = (float) (Math.asin(-rotationMatrix[6]));
   final float cosA = (float) Math.cos(resultingAngles[1]);
   resultingAngles[1] = resultingAngles[1] * rad2deg;
   resultingAngles[2] = (float) (Math.asin(rotationMatrix[2] / cosA))
     * rad2deg;
   resultingAngles[0] = (float) (Math.acos(rotationMatrix[5] / cosA))
     * rad2deg;
  }

  if (MODUS == 11) {
   SensorManager.getRotationMatrix(rotationMatrix, null, accelGData,
     magnetData);
   rotationMatrix = transpose(rotationMatrix);
   /*
    * this assumes that the rotation matrices are multiplied in y z x
    */

   resultingAngles[0] = (float) (Math.asin(rotationMatrix[4]));
   final float cosC = (float) Math.cos(resultingAngles[0]);
   resultingAngles[0] = resultingAngles[0] * rad2deg;
   resultingAngles[2] = (float) (Math.acos(rotationMatrix[0] / cosC))
     * rad2deg;
   resultingAngles[1] = (float) (Math.acos(rotationMatrix[5] / cosC))
     * rad2deg;
  }

  if (MODUS == 12) {
   SensorManager.getRotationMatrix(rotationMatrix, null, accelGData,
     magnetData);
   rotationMatrix = transpose(rotationMatrix);
   /*
    * this assumes that the rotation matrices are multiplied in x z y
    */

   resultingAngles[0] = (float) (Math.asin(-rotationMatrix[1]));
   final float cosC = (float) Math.cos(resultingAngles[0]);
   resultingAngles[0] = resultingAngles[0] * rad2deg;
   resultingAngles[2] = (float) (Math.acos(rotationMatrix[0] / cosC))
     * rad2deg;
   resultingAngles[1] = (float) (Math.acos(rotationMatrix[5] / cosC))
     * rad2deg;
  }
  logOutput();
 }

 /**
  * transposes the matrix because it was transposted (inverted, but here its
  * the same, because its a rotation matrix) to be used for opengl
  * 
  * @param source
  * @return
  */
 private float[] transpose(float[] source) {
  final float[] result = source.clone();
  if (TRY_TRANSPOSED_VERSION) {
   result[1] = source[4];
   result[2] = source[8];
   result[4] = source[1];
   result[6] = source[9];
   result[8] = source[2];
   result[9] = source[6];
  }
  // the other values in the matrix are not relevant for rotations
  return result;
 }

 private void rootMeanSquareBuffer(float[] target, float[] values) {

  final float amplification = 200.0f;
  float buffer = 20.0f;

  target[0] += amplification;
  target[1] += amplification;
  target[2] += amplification;
  values[0] += amplification;
  values[1] += amplification;
  values[2] += amplification;

  target[0] = (float) (Math
    .sqrt((target[0] * target[0] * buffer + values[0] * values[0])
      / (1 + buffer)));
  target[1] = (float) (Math
    .sqrt((target[1] * target[1] * buffer + values[1] * values[1])
      / (1 + buffer)));
  target[2] = (float) (Math
    .sqrt((target[2] * target[2] * buffer + values[2] * values[2])
      / (1 + buffer)));

  target[0] -= amplification;
  target[1] -= amplification;
  target[2] -= amplification;
  values[0] -= amplification;
  values[1] -= amplification;
  values[2] -= amplification;
 }

 private void loadNewSensorData(SensorEvent event) {
  final int type = event.sensor.getType();
  if (type == Sensor.TYPE_ACCELEROMETER) {
   accelGData = event.values.clone();
  }
  if (type == Sensor.TYPE_MAGNETIC_FIELD) {
   magnetData = event.values.clone();
  }
  if (type == Sensor.TYPE_ORIENTATION) {
   orientationData = event.values.clone();
  }
 }

 private void logOutput() {
  if (mCount++ > 30) {
   mCount = 0;
   Log.d("Compass", "yaw0: " + (int) (resultingAngles[0])
     + "  pitch1: " + (int) (resultingAngles[1]) + "  roll2: "
     + (int) (resultingAngles[2]));
  }
 }
}