Class: RenderSystem
Source: ecs/systems/RenderSystem.js, line 6
The RenderSystem is responsible for drawing entities that have a visual representation, specifically those possessing Position and RenderableSprite components. Unlike some systems that perform their main logic during the engine's update loop, this system's core drawing operations occur when its executeRenderPass method is explicitly called, typically by the active game scene during its own render phase.
Extends
Constructor
new RenderSystem()
Creates an instance of the RenderSystem.
Source: ecs/systems/RenderSystem.js, line 6
Members
engine
A reference to the main IroncladEngine instance. This is typically set when the system is registered with the engine.
- Inherited From:
System#engine - Source: ecs/System.js, line 38
requiredComponents
Specifies that this system is interested in entities that have both a "Position" and a "RenderableSprite" component. The engine uses this array to provide the system with relevant entities during its update method.
- Overrides:
System#requiredComponents - Source: ecs/systems/RenderSystem.js, line 18
- Value:
['Position', 'RenderableSprite'](inferred from description)
Methods
executeRenderPass(context, camera)
Executes the rendering pass for all entities that meet the system's component requirements (i.e., have Position and RenderableSprite). This method iterates through the relevant entities and draws their sprites to the provided canvas context, taking into account camera transformations. It is designed to be called by the active scene's render method at the appropriate stage in the rendering pipeline.
Parameters:
| Name | Type | Description |
|---|---|---|
context | CanvasRenderingContext2D | The 2D drawing context of the canvas onto which entities should be rendered. |
camera | Camera | The game camera instance, used to apply viewport and world transformations. |
Source: ecs/systems/RenderSystem.js, line 68
initialize(engine)
Initializes the RenderSystem. This method is called when the system is registered with the IroncladEngine. It can be used to obtain references to engine services or perform one-time setup.
Parameters:
| Name | Type | Description |
|---|---|---|
engine | IroncladEngine | The instance of the game engine. |
- Overrides:
System#initialize - Source: ecs/systems/RenderSystem.js, line 35
shutdown()
Called when the system is unregistered from the IroncladEngine or when the engine is shutting down. This method is useful for any cleanup tasks the system might need to perform, such as releasing resources.
- Inherited From:
System#shutdown - Source: ecs/System.js, line 72
update(deltaTime, entities, engine)
The per-frame update logic for the RenderSystem, called by the IroncladEngine's main system loop. For this particular RenderSystem, the primary drawing logic is encapsulated within the executeRenderPass method, which is called by the scene. Therefore, this update method might be used for tasks like:
- Preparing data for rendering (e.g., culling entities outside the viewport).
- Updating sprite animations if animation logic is part of this system and not handled by a separate
AnimationSystem. - Other pre-rendering calculations.
Currently, its role might be minimal if all drawing is deferred to executeRenderPass.
Parameters:
| Name | Type | Description |
|---|---|---|
deltaTime | number | The time elapsed, in seconds, since the last frame. |
entities | Array<EntityId> | An array of entity IDs that possess the requiredComponents (Position and RenderableSprite). |
engine | IroncladEngine | The instance of the game engine, providing access to other managers and services. |
- Overrides:
System#update - Source: ecs/systems/RenderSystem.js, line 55