Stop following when player left

minecraft-server/src/entities/monsters/zombies.rs

@@ -102,14 +102,19 @@ impl ZombieTask {
     }
 
     /// Returns the movement towards the target that can be applied without colliding with the world.
-    async fn get_movement(&self, h: &Handler<Zombie>, self_position: &Position, target_position: &Position) -> Translation {
+    async fn get_movement(&mut self, h: &Handler<Zombie>, self_position: &Position, target_position: &Position) -> Translation {
         // Create a movement vector
         let mut translation = Translation {
             x: target_position.x - self_position.x,
             y: target_position.y - self_position.y,
             z: target_position.z - self_position.z,
         };
-        if translation.norm() > ZOMBIE_BASE_MOVEMENT_SPEED {
+        let norm = translation.norm();
+        if norm > ZOMBIE_BASE_FOLLOW_RANGE {
+            self.target = None;
+            return Translation::zero();
+        }
+        if norm > ZOMBIE_BASE_MOVEMENT_SPEED {
             translation.set_norm(ZOMBIE_BASE_MOVEMENT_SPEED);
         }
 

minecraft-server/src/world/collisions.rs

@@ -268,14 +268,18 @@ impl<'a> Iterator for PointIter<'a> {
 }
 
 /// Vector describing a movement
-#[derive(Debug, Clone, PartialEq)]
+#[derive(Debug, Default, Clone, PartialEq)]
 pub struct Translation {
     pub x: f64,
     pub y: f64,
     pub z: f64,
 }
 
 impl Translation {
+    pub fn zero() -> Self {
+        Self::default()
+    }
+
     pub fn yaw_pitch(&self) -> (f32, f32) {
         let r = (self.x * self.x + self.y * self.y + self.z * self.z).sqrt();
         let pitch = -(self.y / r).asin() / std::f64::consts::PI * 180.0;