撕衣服小游戏原理

/*撕衣服原理：
底层放无衣服人物，上层放穿衣服人物
当触摸划过使上层划过像素变透明*/public class MainActivity extends Activity {private ImageView iv;private Bitmap srcBM;private Bitmap copyBM;private Canvas canvas;private Paint paint;private Matrix matrix;protected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);iv = (ImageView) findViewById(R.id.iv);srcBM = BitmapFactory.decodeResource(getResources(), R.drawable.pre);copyBM = Bitmap.createBitmap(srcBM.getWidth(),srcBM.getHeight(), srcBM.getConfig());canvas = new Canvas(copyBM);paint = new Paint();matrix = new Matrix();canvas.drawBitmap(srcBM, matrix, paint);iv.setImageBitmap(copyBM);iv.setOnTouchListener(new OnTouchListener() {@Overridepublic boolean onTouch(View v, MotionEvent event) {int action = event.getAction();switch (action) {case MotionEvent.ACTION_MOVE:int x = (int) event.getX();int y = (int) event.getY();for(int i = -15;i < 15;i++){for(int j = -10;j < 10;j++){copyBM.setPixel(x+i, y+j, Color.TRANSPARENT);}}iv.setImageBitmap(copyBM);                  break;}return true;}});}
}