Box2d Box2d Box2d Box2d Box2d Box2d Box2d Box2d Box2d Box2d center contains contains contains contains deflate deflate deflate deflate deflate empty get get get height inflate inflate inflate inflate inflate intersectWith intersectWith isEmpty isEmptyMinus isEqualTo isIntersect isNormalized isNull kIdentity leftBottom leftTop normalize offset offset offset operator & operator &= operator!= operator* operator* operator*= operator*= operator+ operator+ operator+= operator+= operator- operator- operator-= operator-= operator/ operator/= operator== operator| operator|= rightBottom rightTop scaleBy set set set set set set size swapTopBottom unionWith unionWith unionWith unionWith width xmax xmin ymax ymin

scaleBy() Box2d& Box2d::scaleBy ( float  sx, float  sy = 0  ) 比例放缩，以原点为中心 参数 sx X方向放缩比例 sy Y方向放缩比例，为0则取为sx 返回 本矩形的引用 函数调用图: