add angle angle2 angledVector angleTo angleTo2 crossProduct distanceToVector dotProduct get isCodirectionalTo isCodirectionalTo isDegenerate isEqualTo isLeftOf isOppositeTo isOppositeTo isParallelTo isParallelTo isPerpendicularTo isPerpendicularTo isRightOf isUnitVector isZeroVector kIdentity kXAxis kYAxis length lengthSquare negate normalize operator!= operator* operator* operator* operator* operator* operator*= operator*= operator+ operator+= operator- operator- operator-= operator/ operator/ operator/= operator== perpVector projectResolveVector projectScaleToVector resolveVector resolveVector scaleBy scaleBy scaledVector set set setAngleLength setLength subtract transform unitVector Vector2d Vector2d Vector2d x y

distanceToVector() float Vector2d::distanceToVector ( const Vector2d &  xAxis ) const 求本矢量投影到矢量xAxis上的垂直距离 在xAxis的逆时针方向时返回正值，顺时针则返回负值 参数 [in] xAxis 投影到的矢量 返回 垂直投影距离，有正负 函数调用图: 这是这个函数的调用关系图: