public static void scaleRectAboutCenter(Rect r,float scale){
  if (scale != 1.0f) {
    int cx=r.centerX();
    int cy=r.centerY();
    r.offset(-cx,-cy);
    r.left=(int)(r.left * scale + 0.5f);
    r.top=(int)(r.top * scale + 0.5f);
    r.right=(int)(r.right * scale + 0.5f);
    r.bottom=(int)(r.bottom * scale + 0.5f);
    r.offset(cx,cy);
  }
}

public static void scaleRectAboutCenter ( Rect r , float scale ) { if ( scale != 1.0f ) { int cx = r . centerX ( ) ; int cy = r . centerY ( ) ; r . offset ( - cx , - cy ) ; r . left = ( int ) ( r . left * scale + 0.5f ) ; r . top = ( int ) ( r . top * scale + 0.5f ) ; r . right = ( int ) ( r . right * scale + 0.5f ) ; r . bottom = ( int ) ( r . bottom * scale + 0.5f ) ; r . offset ( cx , cy ) ; } }
scales a rect about its centroid
