38 lines
1.4 KiB
Markdown
38 lines
1.4 KiB
Markdown
# Entity
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### Contents
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[About](#About)
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[Usage](#Usage)
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[Notes](#Notes)
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## About
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An 'entity' is a unique ID.
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For most implementations, it makes sense to use a simple integer value - usually in a packed array (*reuses the most minimal value it can*)
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E.g.: The ID 101 would be the next selected value for a new entity.
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>100 | 101 | 102| 103| 104| ...|
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>:----:|:-----:|:----:|:----:|:----:|:----|
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><span style="color:gray">used|unused|<span style="color:gray">used|<span style="color:gray">used| unused| <span style="color:gray">....
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<br>
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**This ID represents a specific instance of a game object**
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e.g. character, vehicle, effect etc.
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___An entity contains no further data.___
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In order to be useful, its identifier must be registered to one or more [components](././component/component.md).
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## Usage
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*some specific usage info here*
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``` java
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void todo();
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```
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## Notes
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* The only requirement for a Entity is that it has a unique ID. An [entity manager](././manager/entity_manager.md) could implement a more complex ID system such as using a packed array for only a small region of IDs, or using named IDs by use of a dictionary or ordered hash-map
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* The maximum number of entities is limited by the size of the container used to store it. E.g., for a 32-bit unsigned integer, there are ~4.3 billion ID's available. But keep in mind that such a large amount of IDs will take significant time for each system to consider.
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