谷歌地图在iOS中按照设备方向绘制折线

I'am doing a navigation App, that uses Google map direction API, i ask Google Api to draw path between two coordinates with "driving mode", and i draw it on map. I have an issue when i'm driving, i recalculate path from my current location to some destination location, but the path i get is not following up my device direction,it runs in the opposite direction when i'am driving in a double direction road. I'am doing a navigation App, that uses Google m