104 lines
2.5 KiB
C#
104 lines
2.5 KiB
C#
using System;
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namespace ET
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{
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public struct EntityRef<T> where T: Entity
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{
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private readonly long instanceId;
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private T entity;
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private EntityRef(T t)
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{
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if (t == null)
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{
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this.instanceId = 0;
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this.entity = null;
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return;
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}
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this.instanceId = t.InstanceId;
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this.entity = t;
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}
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private T UnWrap
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{
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get
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{
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if (this.entity == null)
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{
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return null;
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}
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if (this.entity.InstanceId != this.instanceId)
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{
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// 这里instanceId变化了，设置为null，解除引用，好让runtime去gc
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this.entity = null;
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}
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return this.entity;
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}
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}
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public static implicit operator EntityRef<T>(T t)
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{
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return new EntityRef<T>(t);
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}
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public static implicit operator T(EntityRef<T> v)
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{
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return v.UnWrap;
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}
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}
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public struct EntityWeakRef<T> where T: Entity
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{
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private long instanceId;
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// 使用WeakReference，这样不会导致entity dispose了却无法gc的问题
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// 不过暂时没有测试WeakReference的性能
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private readonly WeakReference<T> weakRef;
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private EntityWeakRef(T t)
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{
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if (t == null)
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{
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this.instanceId = 0;
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this.weakRef = null;
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return;
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}
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this.instanceId = t.InstanceId;
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this.weakRef = new WeakReference<T>(t);
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}
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private T UnWrap
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{
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get
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{
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if (this.instanceId == 0)
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{
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return null;
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}
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if (!this.weakRef.TryGetTarget(out T entity))
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{
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this.instanceId = 0;
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return null;
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}
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if (entity.InstanceId != this.instanceId)
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{
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this.instanceId = 0;
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return null;
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}
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return entity;
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}
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}
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public static implicit operator EntityWeakRef<T>(T t)
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{
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return new EntityWeakRef<T>(t);
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}
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public static implicit operator T(EntityWeakRef<T> v)
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{
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return v.UnWrap;
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}
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}
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} |