I am plotting real time trajectories on a map full of obstacles.
The obstacles are polygons and my domain is 2D.
I would like to color in red trajectories of bodies that cross an obstacle,
to show that this is unphysical. Of course, that part of the trajectory has to change colour.
Trajectories are plotted in real time according to a running simulation.
I believe that checking at every iteration whether all the trajectories coincide with the contour of the
obstacles would kill the performance.