cocos2dx和lua计算两点的夹角

lua:

--[[-- @param p1 A点 p2 B点  返回以A为比较点 B相对于A的夹角 范围为-180度到180度]]function getAngleByPos(p1,p2)    local p = {}    p.x = p2.x - p1.x    p.y = p2.y - p1.y               local r = math.atan2(p.y,p.x)*180/math.pi    print("夹角[-180 - 180]:",r)    return rend

cocos2dx:

CCPoint endPos = CCPoint(0, 500);CCPoint startPos = CCPoint(500, 0);CCPoint dis = endPos - startPos;float t = CCPoint(dis.y, dis.x).getAngle() / 3.14f * 180;//一定注意x和y参数是倒过来的