🎱 Interaction

The Interaction trait is responsible for modeling physical interactions between cellular agents. It can also be used to detect and react to neighbors.

The calculate_force_between method calculates forces acting on the two cells in question which will then later be used to update the position and velocity via the mechanics concept. We can also exchange information between the cells which is not related to their position or velocity via the get_interaction_information method.

pub trait Interaction<Pos, Vel, Force, Inf = ()> {
    fn get_interaction_information(&self) -> Inf;

    fn calculate_force_between(
        &self,
        own_pos: &Pos,
        own_vel: &Vel,
        ext_pos: &Pos,
        ext_vel: &Vel,
        ext_info: &Inf
    ) -> Result<(Force, Force), CalcError>;

Furthermore, to model reactions to neighbors, the trait provides the is_neighbor and react_to_neighbors methods which are used to first count the number of neighbors and then react accordingly.

    // Provided methods
    fn is_neighbor(
        &self,
        own_pos: &Pos,
        ext_pos: &Pos,
        ext_inf: &Inf
    ) -> Result<bool, CalcError> {
        Ok(false)
    }

    fn react_to_neighbors(&mut self, neighbors: usize) -> Result<(), CalcError> {Ok(())}
}

Their default functionality is to never count and do no interactions.

Examples

When representing cells as point-like particles, we can employ classical interactions given by interaction potentials such as the MorsePotential, MiePotential or BoundLennardJones potential.

Other examples of complex interactions between cells are

• Semi-Vertex cells
• Bacterial Rods