63 lines
1.6 KiB
Markdown
63 lines
1.6 KiB
Markdown
*| [JavaECS](../../README.md) | [docs](../overview.md) | [system](./dir.md) | system[]().md*
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# System
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### In this section
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[About](#About)
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[Implementation](#Implementation)
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[Examples](#Examples)
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[Notes](#Notes)
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## About
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The system runs operations that must be performed on its assoiciated components.
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Typically, this is expected to be run every frame, though this is not a strict requirement.
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A system must implement the Runnable interface (this is a limited case of inheritence in this library)
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This allows a simpler implementation of any system, and also allows concurrency to be implemented with relative ease.
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Examples of the `system` include the `health_system`; which reads the value of the entitie's `health` component and ensures h > 0.
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``` java
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void health_system(){
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for (i = 0; i < registeredComponents.size(); i++){
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if (registeredComponents[i].health <= 0){
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registeredComponents[i].dead = true;
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if (registeredComponents[i].isPlayer){
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GameOver();
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}
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}
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}
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}
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```
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## Implementation
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The systems are managed by the following code:
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``` java
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class SystemManager{
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ECS baseECS;
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int systemIndex;
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public SystemManager(ECS baseECS){
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this.baseECS = baseECS;
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systemIndex = 0;
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}
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}
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```
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## Examples
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## Notes
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* Each system is represented by a name-index pair, and the action that gets executed every time the system is performed.
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* This is implicitly sequential, but a custom system that performs concurrent actions can be implemented.
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* Care must be taken to ensure all threads are synchronised before the concurrent system finishes its execution
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