Multi-touch 구현
public boolean onTouchEvent(final MotionEvent event) { final int action = event.getAction(); if(mIsMultiTouchSupported) { switch (action & MotionEvent.ACTION_MASK) { case MotionEvent.ACTION_POINTER_DOWN : { if(mActivePointerId == -1) { final int pind = (action & MotionEvent.ACTION_POINTER_INDEX_MASK) >> MotionEvent.ACTION_POINTER_INDEX_SHIFT; int pid = event.getPointerId(pind); final int x = (int)event.getX(pid); final int y = (int)event.getY(pid); if(pointInArea(x, y)) { mActivePointerId = pid; // System.out.println("down pointer x = "+x+" , y = "+y); onAction(UIAREA_ACTION_DOWN, x, y); } } } break; case MotionEvent.ACTION_DOWN: { if(mActivePointerId == -1) { final int x =...