rg1/client/Battle/System/DropItem/DoDropSystem.cs

using Entitas;
using UnityEngine;

namespace CoreGame.Render
{
    public class DoDropSystem : IExecuteSystem
    {
        readonly IGroup<CombatEntity> m_Group;
        public DoDropSystem(Contexts contexts)
        {
            // 获取所有带有DropFlag的实体,一定有dropData
            m_Group = contexts.combat.GetGroup(CombatMatcher.DoDrop);
        }

        public void Execute(float deltaTime)
        {
            m_Group.GetEntities(Contexts.s_CacheEntities);
            if (Contexts.s_CacheEntities.Count == 0)
                return;
            
            var entities = Contexts.s_CacheEntities;
            for (int i = 0; i < entities.Count; i++)
            {
                DropItem(entities[i], deltaTime);
            }
        }
        
        private void DropItem(CombatEntity entity, float dt)
        {
            var doDrop = entity.doDrop;
            doDrop.accTime += dt;
            if (doDrop.accTime > doDrop.duration)
            {
                entity.RemoveDoDrop();
                return;
            }

            var et = entity.transformProxy;
            if (et == null)
                return;
            
            var t = doDrop.accTime / doDrop.duration;
            var start = doDrop.startPos;
            var end = doDrop.targetPos;
            var pos = Mathf.Pow(1 - t, 2) * start + 2 * t * (1 - t) * doDrop.bezierCtrl1 + Mathf.Pow(t, 2) * end;
            et.SetPosition(pos);
            var lerp = Mathf.Lerp(doDrop.startScale, doDrop.targetScale, doDrop.accTime / doDrop.duration);
            et.SetLocalScale(Vector2.one * lerp);
            // if (BattleModule.Instance.worldType != WorldType.Battle)
            {
                et.Sync();
                et.Flush();
            }
        }
    }
}