72 lines
1.7 KiB
C++
72 lines
1.7 KiB
C++
#include "Types.hpp"
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#include <array>
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#include <cassert>
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#include <queue>
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#ifndef WINDOW_H
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#define WINDOW_H
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class EntityManager
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{
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private:
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// Queue of unused entity IDs
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std::queue<Entity> mAvailableEntities{};
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// Array of signatures where the index corresponds to the entity ID
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std::array<Signature, MAX_ENTITIES> mSignatures{};
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// Total living entities - used to keep limits on how many exist
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uint32_t mLivingEntityCount{};
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public:
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EntityManager()
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{
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// Initialize the queue with all possible entity IDs
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for (Entity entity = 0; entity < MAX_ENTITIES; ++entity)
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{
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mAvailableEntities.push(entity);
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}
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}
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Entity CreateEntity()
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{
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assert(mLivingEntityCount < MAX_ENTITIES && "Too many entities in existence.");
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// Take an ID from the front of the queue
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Entity id = mAvailableEntities.front();
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mAvailableEntities.pop();
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++mLivingEntityCount;
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return id;
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}
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void DestroyEntity(Entity entity)
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{
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assert(entity < MAX_ENTITIES && "Entity out of range.");
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// Invalidate the destroyed entity's signature
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mSignatures[entity].reset();
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// Put the destroyed ID at the back of the queue
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mAvailableEntities.push(entity);
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--mLivingEntityCount;
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}
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void SetSignature(Entity entity, Signature signature)
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{
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assert(entity < MAX_ENTITIES && "Entity out of range.");
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// Put this entity's signature into the array
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mSignatures[entity] = signature;
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}
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Signature GetSignature(Entity entity)
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{
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assert(entity < MAX_ENTITIES && "Entity out of range.");
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// Get this entity's signature from the array
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return mSignatures[entity];
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}
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};
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#endif |