Constant screeps::constants::tower::TOWER_FALLOFF

pub const TOWER_FALLOFF: f64 = 0.75;

Maximum percentage reduction in healing, repair, and attack effectiveness for towers due to range.

When targets are at range beyond TOWER_OPTIMAL_RANGE until reaching the maximum penalty at range TOWER_FALLOFF_RANGE, the amount of healing, repair, or damage done by a tower is reduced according to the formula (source):

amount -= amount * TOWER_FALLOFF * (range - TOWER_OPTIMAL_RANGE) / (TOWER_FALLOFF_RANGE - TOWER_OPTIMAL_RANGE)