angle coordSystem coordSystem det dx dy getCoordSystem hasMirror inverse invert isConformal isEqualTo isIdentity isInvertible isOrtho kIdentity m11 m12 m21 m22 Matrix2d Matrix2d Matrix2d Matrix2d mirroring mirroring operator!= operator* operator* operator* operator*= operator*= operator/ operator/= operator== postMultBy preMultBy rotation scale scaleBy scaleBy scaleX scaleY scaling scaling set setCoordSystem setToIdentity setToMirroring setToMirroring setToProduct setToRotation setToScaling setToScaling setToShearing setToTranslation shearing transformPoints transformVectors transformWith2P translation

setToRotation() Matrix2d & Matrix2d::setToRotation ( float  angle, const Point2d &  center = Point2d::kOrigin()  ) 设置为以一点为中心的旋转变换矩阵 参数 angle 旋转角度，弧度，逆时针为正 center 旋转中心点 返回 改变后的本对象的引用 这是这个函数的调用关系图: