一说到3D，可能第一反应就是使用OpenGL ES。。。。但是，实现这么个小功能，要动用这玩意，莫名的恐惧啊！！！！至今也没弄明白这个怎么玩。。。
好吧，幸亏还有个Camera类可以帮助我们，据说底层实现实现也是使用的是OpenGL ES
注意：使用的是android.graphics.Camera
话不多说了，直接上代码：
public class _3DAnimation extends Animation {
private float mFromDegrees;
private float mToDegrees;
private float mCenterX;
private float mCenterY;
private Camera mCamera;
public _3DAnimation(float fromDegress,float toDegress){
this.mFromDegrees=fromDegress;
this.mToDegrees=toDegress;
}
@Override
public void initialize(int width, int height, int parentWidth, int parentHeight) {
super.initialize(width, height, parentWidth, parentHeight);
this.mCenterX=width/2;
this.mCenterY=height/2;
mCamera=new Camera();
}
@Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
super.applyTransformation(interpolatedTime, t);
final float fromDegrees = mFromDegrees;
float degrees = fromDegrees + (mToDegrees - mFromDegrees) * interpolatedTime;
final Matrix matrix = t.getMatrix();
//interpolatedTime 0~1变化
mCamera.save();
mCamera.rotateY(degrees);
mCamera.getMatrix(matrix);
mCamera.restore();
matrix.preTranslate(-mCenterX, -mCenterY);//相机位于（0,0），移动图片，相机位于图片中心
matrix.postTranslate(mCenterX, mCenterY);
}
}