49 lines
951 B
GDScript
49 lines
951 B
GDScript
class_name LRU extends RefCounted
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# LRU 算法
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var cache_size = 1
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# keys. 新的在后面，旧的在前面
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var lru_list = []
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# key -> value
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var cache = {}
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var cache_mutex = Mutex.new()
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func _init(size := 8) -> void:
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cache_size = size
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func _get(key: Variant) -> Variant:
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var v = null
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cache_mutex.lock()
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if cache.has(key):
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lru_list.erase(key)
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lru_list.append(key)
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v = cache[key]
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cache_mutex.unlock()
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return v
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func _set(key: StringName, value: Variant) -> bool:
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cache_mutex.lock()
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if cache.has(key):
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lru_list.erase(key)
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if cache[key] != value:
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_release_value(cache[key])
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cache[key] = value
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lru_list.append(key)
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if lru_list.size() > cache_size:
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var k = lru_list.pop_front()
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_release_value(cache[k])
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cache.erase(k)
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cache_mutex.unlock()
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return true
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func _release_value(v: Variant) -> void:
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if v is Node:
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if not v.is_inside_tree() and is_instance_valid(v):
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v.queue_free()
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elif not v is RefCounted:
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v.free()
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