easy question unless ur new to all this.... (moving)

ok..
Pls note that I take a BASE position from my "player agent", but the agent is not moved.

so i have my Agent and to find the surface in front of me, I use ray tracing..... to find the exact collision point.
(since it is not a flat surface)

Now what i want to do is add an offset to that in the direction i'm looking, (currently for testing )
I'm using....

Code (CSharp):

1.  
2. basepos.x += 1f;
3. basepos.z += 1f;
4.  

I iterate round a loop,which lays down a "straight line".. along a path but clearly not always in the direction i'm looking .(but my items ARE nicely following the contours of the surface)


I think i can get my "looking" direction from

Code (CSharp):

1. ray.direction

but how do I generate a new position to test ?, how do i "sum" vectors in space?