HELP! How to guide my vehicle?

Projects Programming
3

Thank you for answer, but I can't figure out how to code for orient the car toward waypoints.

I mean, for example:
//Number of Waypoints
int waypoints[] = {0,1,2,3};

/Actual Waypoint
int WaypointNow=0;

//Positions of Waypoints

//Waypoint A
float wALong=1,2345;
float wALati=1,2345;

//Waypoint B
float wBLong=1,2346;
float wBLati=1,2346;

//Here's come the common code and then...

switch(WaypointNow){

case 0:
if(GPS.Longitude <= wALong && GPS.Latitude <= wALati){
WaypointNow++;
WaypointHeading?
}
break;

case 1:
if(GPS.Longitude <= wBLong && GPS.Latitude <= wBLati){
WaypointNow++;
WaypointHeading?
}
break;

}

My problem is how to get the new waypoint heading. Orientate the car. For example, now I'm oriented the North but for go to the next waypoint that is at west, I need rotate the car to X degrees to get the angle and move forwards the vehicle to reach next waypoint.

Thanks.