Created a typedef for a mask object to abstract the mask creation away from the user and placed it in vector.h.

Don't need to load unneeded quantities until they are actually left-packed into the interaction cache.

Quicker to find neighbours with only 1 vector and no need to mask result of interaction if the remainder interactions have already been performed.

Pass vectors by address instead of value and use 2 vectors to find neighbours in runner_doself2_force_2.

Crucial +1 for the edge case where all particles in cell ci interact with at least one particle in cell cj.

Updated runner_doself1_density_vec and runner_dopair1_density_vec to align with Pedro's recent changes in DOPAIR1 and DOSELF1.

runner_doself2_force_vec_3 now passes addresses of the interaction cache to the interaction function.

Created a runner_doself2_force_vec function. Multiple variations, runner_doself2_force_vec vectorises straight from the serial. runner_doself2_force_vec_2 vectorises by caching properties needed in the interaction. runner_doself2_force_vec_3 builds on runner_doself2_force_vec_2 and stores the interactions in a secondary cache and performs interaction after looping over all possible pj particles.

Only loop over particles that are within range and active. Removed if statement that should never be true.

Check if there are any active particles within interaction distance and return if there are not. Only populate the cache from the first particle in a cell that interacts*and* is also active.

Perform padding of the cache when populating it instead of on the fly. Create fake particles to be maxed out in the inner interaction loop.