public class Rotate3dAnimation extends Animation {
private final float mFromDegrees;
private final float mToDegrees;
private final float mCenterX;
private final float mCenterY;
private final float mDepthZ;
private final boolean mReverse;
private Camera mCamera;
/**
* Creates a new 3D rotation on the Y axis. The rotation is defined by its
* start angle and its end angle. Both angles are in degrees. The rotation
* is performed around a center point on the 2D space, definied by a pair
* of X and Y coordinates, called centerX and centerY. When the animation
* starts, a translation on the Z axis (depth) is performed. The length
* of the translation can be specified, as well as whether the translation
* should be reversed in time.
*
* @param fromDegrees the start angle of the 3D rotation
* @param toDegrees the end angle of the 3D rotation
* @param centerX the X center of the 3D rotation
* @param centerY the Y center of the 3D rotation
* @param reverse true if the translation should be reversed, false otherwise
*/
public Rotate3dAnimation(float fromDegrees, float toDegrees,
float centerX, float centerY, float depthZ, boolean reverse) {
mFromDegrees = fromDegrees;
mToDegrees = toDegrees;
mCenterX = centerX;
mCenterY = centerY;
mDepthZ = depthZ;
mReverse = reverse;
}
@Override
public void initialize(int width, int height, int parentWidth, int parentHeight) {
super.initialize(width, height, parentWidth, parentHeight);
mCamera = new Camera();
}
@Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
final float fromDegrees = mFromDegrees;
float degrees = fromDegrees + ((mToDegrees - fromDegrees) * interpolatedTime);
final float centerX = mCenterX;
final float centerY = mCenterY;
final Camera camera = mCamera;
final Matrix matrix = t.getMatrix();
//保存一次camera初始状态，用于restore()
camera.save();
if (mReverse) {
camera.translate(0.0f, 0.0f, mDepthZ * interpolatedTime);
} else {
camera.translate(0.0f, 0.0f, mDepthZ * (1.0f - interpolatedTime));
}
//围绕Y轴旋转degrees度
camera.rotateY(degrees);
//行camera中取出矩阵，赋值给matrix
camera.getMatrix(matrix);
//camera恢复到初始状态，继续用于下次的计算
camera.restore();
matrix.preTranslate(-centerX, -centerY);
matrix.postTranslate(centerX, centerY);
}
}
Test3DRotateActivity.java
public class Test3DRotateActivity extends Activity {
/** Called when the activity is first created. */
private final String TAG="Test3DRotateActivity";
private ImageView image;
private Button start ,stop;
private Rotate3dAnimation rotation;
private StartNextRotate startNext;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
image = (ImageView) findViewById(R.id.image);
start=(Button) findViewById(R.id.start);
stop = (Button) findViewById(R.id.stop);
start.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
//进行360度的旋转
startRotation(0,360);
}
});
stop.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
image.clearAnimation();
}
});
}
private void startRotation(float start, float end) {
// 计算中心点
final float centerX = image.getWidth() / 2.0f;
final float centerY = image.getHeight() / 2.0f;
Log.d(TAG, "centerX="+centerX+", centerY="+centerY);
// Create a new 3D rotation with the supplied parameter
// The animation listener is used to trigger the next animation
//final Rotate3dAnimation rotation =new Rotate3dAnimation(start, end, centerX, centerY, 310.0f, true);
//Z轴的缩放为0
rotation =new Rotate3dAnimation(start, end, centerX, centerY, 0f, true);
rotation.setDuration(2000);
rotation.setFillAfter(true);
//rotation.setInterpolator(new AccelerateInterpolator());
//匀速旋转
rotation.setInterpolator(new LinearInterpolator());
//设置监听
startNext = new StartNextRotate();
rotation.setAnimationListener(startNext);
image.startAnimation(rotation);
}
private class StartNextRotate implements AnimationListener{
public void onAnimationEnd(Animation animation) {
// TODO Auto-generated method stub
Log.d(TAG, "onAnimationEnd......");
image.startAnimation(rotation);
}
public void onAnimationRepeat(Animation animation) {
// TODO Auto-generated method stub
}
public void onAnimationStart(Animation animation) {
// TODO Auto-generated method stub
}
}
}
