Implement hitstun and knockback.

src/fighter/state/ground_attack.rs

@@ -26,14 +26,19 @@ impl FighterStateImpl for GroundAttackState {
     }
 
     fn update(&mut self, state_context: &mut super::FighterStateContext) {
+        let animation_frame = state_context.get_current_animation_frame();
         let script = state_context
             .attack_scripts
             .get(&state_context.attack_script_assets.scripts[&self.attack_kind]);
         if let Some(script) = script {
-            let animation_frame = state_context.get_current_animation_frame();
             update_active_hitbox_list(
                 script,
-                &mut state_context.hitboxes.active_hitboxes,
+                &mut state_context
+                    .hitboxes
+                    .0
+                    .as_mut()
+                    .expect("ground attack must have active hitboxes")
+                    .active_hitboxes,
                 animation_frame,
             );
         }
@@ -41,13 +46,19 @@ impl FighterStateImpl for GroundAttackState {
 
     fn on_enter(&mut self, state_context: &mut super::FighterStateContext) {
         state_context.play_animation(self.attack_kind.get_animation(), false);
-        state_context.hitboxes.attack_script =
-            Some(state_context.attack_script_assets.scripts[&self.attack_kind].clone());
-        state_context.hitboxes.active_hitboxes.clear();
+        let script = state_context.attack_script_assets.scripts[&self.attack_kind].clone();
+        state_context.stale_move_queue.push(self.attack_kind);
+        state_context.hitboxes.0 = Some(crate::fighter::FighterActiveAttack {
+            kind: self.attack_kind,
+            script,
+            active_hitboxes: Vec::new(),
+            solved_hitboxes: Vec::new(),
+            hit_fighters: Vec::new(),
+        });
     }
 
     fn on_exit(&mut self, state_context: &mut super::FighterStateContext) {
-        state_context.hitboxes.clear();
+        state_context.hitboxes.0 = None;
     }
 
     fn check_collision_interrupt(