Misaki
d8a7b07624
- Refactor D3D12 backend and RenderGraph module - Update graphics RHI and core rendering components - Add Random.hlsl shader include - Regenerate API documentation and update user guides
89 lines
2.4 KiB
Markdown
89 lines
2.4 KiB
Markdown
# Getting Started with Ghost.Entities
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GhostEngine's Entity Component System (ECS) is a high-performance, Data-Oriented architecture designed for C# .NET 10. The ECS runtime is strictly AOT-compatible and focuses on unmanaged data structures to maximize cache locality and performance.
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## Initialization
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The core of the ECS is the `World`. A `World` contains an `EntityManager`, `ComponentManager`, and `SystemManager`.
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To get started, you must create a `World`:
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```csharp
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using Ghost.Entities;
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// Create a new World with a default entity capacity of 16
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World world = World.Create();
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```
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## Creating Entities and Adding Components
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Entities are simply IDs that point to a combination of components. You use the `EntityManager` to create and modify them.
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First, define your unmanaged components:
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```csharp
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public struct Position : IComponent
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{
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public float X, Y, Z;
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}
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public struct Velocity : IComponent
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{
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public float X, Y, Z;
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}
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```
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Then, create entities and attach components:
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```csharp
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using Ghost.Core;
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using Misaki.HighPerformance.LowLevel.Buffer;
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// Creating a ComponentSet for fast archetype initialization
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using var scope = AllocationManager.CreateStackScope();
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var componentSet = new ComponentSet(
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scope.AllocationHandle,
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ComponentTypeID<Position>.Value,
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ComponentTypeID<Velocity>.Value
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);
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// Create 1000 entities with both Position and Velocity
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world.EntityManager.CreateEntities(1000, componentSet);
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```
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## Adding Systems and Updating
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Systems contain the logic that operates on the component data. You add systems to the `SystemManager` and run them inside a loop.
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```csharp
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// Get the DefaultSystemGroup to attach systems
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var group = world.SystemManager.GetSystem<DefaultSystemGroup>();
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// Add custom systems
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group.AddSystem<MovementSystem>();
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// Sort systems based on their dependencies
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group.SortSystems();
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// Initialize all systems
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world.SystemManager.InitializeAll(new TimeData());
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// Update loop
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while (running)
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{
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world.SystemManager.UpdateAll(timeData);
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world.PlaybackEntityCommandBuffers();
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}
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// Cleanup at the end
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world.Dispose();
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```
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## Summary
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In GhostEngine ECS:
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1. **World** manages the lifecycle of your ECS data.
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2. **Components** (`IComponent`) are unmanaged data structures.
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3. **Entities** are logical containers combining those components into archetypes.
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4. **Systems** (`SystemBase`) execute logic over arrays of components using `EntityQuery`.
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