Hi Guys, i'm new to the R community (so sorry if this isn't the right place to ask such a question).

I have decimal latitude, longitude GPS co-ordinates, an angle and a distance, and I am trying to find the GPS coordinates of the new point. However, the angle has not been calculated from a compass (or true north). For example:

The observer travels along a transect line and records sightings.As they came across an animal they would record the gps location of the current point, as well as the distance and angle of their location relative to vessel's centre line (0 degrees is the centre, looking perpendicular to the left is -90 and looking perpendicular to the right is 90).

I was wondering whether there was a code to calculate the new gps location. What I've found on google are formulas but using angle in relation to the north (e.g. 90 would be east, 180 south etc.). Here, the angle has nothing to do with North/South bearings, just the angle from the direction of the moving vehicle. Does that affect it at all?

Thanks