This is another shallow bidding equation, similar to the direct distance, 
however we consider the agent heading

b = dist*(0.75-0.25*cos(phi))

Where phi is the heading to the target. If the heading is antiparallel to the direction to the target, 
we end up with a negative number, and consider the full distance 

If an agent is facing towards the target already, we consider half the distance 

This is merely a means of achieving a bid which includes heading, and goes no further than providing a weighting schema

To use the dynamic loading of behaviors, you need to set the following 
environment variable (in your .cshrc file for tcsh users, or the equivalent
for bash users):

setenv IVP_BEHAVIOR_DIRS '/home/bob/moos-ivp-swarm/lib'