Renderer

Base class for renderers. Represents the graphics rendering target (typically a canvas). The renderer provides a factory interface to create rendering objects (PolyListRenderer, MaterialRenderer, TextureRenderer, Pipeline, etc.).

The base class defines abstract methods that are implemented by concrete renderers. The current implementation is WebGL-based.

import Renderer from "bg2e-js/ts/render/Renderer.ts";

See also webgl/Renderer.js for the WebGL implementation (WebGLRenderer).

EngineFeatures Enum

Defines supported rendering features:

import { EngineFeatures } from "bg2e-js/ts/render/Renderer.ts";

const supportsRTT = renderer.supportsFeatures(EngineFeatures.RENDER_TARGET_TEXTURES);

• RENDER_TARGET_TEXTURES (0x1 << 0) — Supports render-to-texture via WebGL extensions.
• RENDER_TARGET_FLOAT (0x1 << 1) — Supports floating-point render targets.
• RENDER_TARGET_DEPTH (0x1 << 2) — Supports depth render targets.

Constructor

constructor(identifier: string)

• identifier — A string identifier for the renderer (e.g., “webgl”).

Properties (Read)

• frameBuffer — Returns the FrameBuffer instance associated with this renderer.
• canvas — Returns the Canvas linked to this renderer.
• factory — Returns a RendererFactory interface for creating rendering objects.

Methods (WebGL Implementation: WebGLRenderer)

import WebGLRenderer from "bg2e-js/ts/render/webgl/Renderer.js";

const renderer = new WebGLRenderer();

async init(canvas: Canvas): Promise<void>

Initializes the renderer with a canvas. Creates the WebGL context internally.

get gl(): WebGLRenderingContext

Returns the raw WebGLRenderingContext object (WebGL1). Used for direct WebGL API calls from custom shaders.

get frameBuffer(): FrameBuffer

Returns the WebGLFrameBuffer instance. Use frameBuffer.clear() to clear buffers.

set viewport(vp: Vec) / get viewport(): Vec

Set/get the viewport dimensions. Typically called in reshape() and synced with canvas size on every frame update.

get uniqueId(): string

Returns a unique identifier for this renderer instance (string).

get typeId(): string

Returns the type name, "WebGL".

postReshape(width: number, height: number): void

Called when the canvas is resized. Should forward to renderer.state.viewport = new Vec(width, height).

postRedisplay(): void

Triggers a redraw in the next frame.

supportsFeatures(feature: number): boolean

Checks if a specific EngineFeature is supported. Returns true/false.

getMaximumRenderTargets(): number

Returns the maximum number of simultaneous render targets. Typically 1 for WebGL1.

clearBuffer(): void

Clears the current frame buffer (equivalent to calling state.clear()).

get state(): State

Returns the State object, which provides access to WebGL rendering parameters (clearColor, viewport, depthTestEnabled, etc.).

get debugMode(): boolean

Returns true if WebGL debugging is enabled. Debugging can be enabled by appending ?debug=true to the URL.

RendererFactory Interface

The factory creates all rendering-specific objects:

const factory = renderer.factory;

Method	Returns	Description
factory.polyList(plist)	PolyListRenderer	Wraps a PolyList with a renderer
factory.material(material)	MaterialRenderer	Wraps a Material with a renderer
factory.texture(texture)	TextureRenderer	Wraps a Texture for rendering operations
factory.renderBuffer()	RenderBuffer	Creates a new RenderBuffer for RTT/cubemap operations
factory.skySphere()	SkySphere	Creates a new SkySphere instance
factory.skyCube()	SkyCube	Creates a new SkyCube instance
factory.environment()	Environment	Creates an Environment for IBL
factory.textureMerger()	TextureMergerRenderer	Creates a TextureMerger for merging channels from multiple textures
factory.pipeline()	Pipeline	Creates a new Pipeline for configuring blend state, depth/cull settings
factory.scene()	SceneRenderer	Creates a new SceneRenderer for scene-graph rendering
factory.shadowRenderer()	ShadowRenderer	Creates a ShadowRenderer for shadow map generation

Abstract Methods (Base class)

The base Renderer defines the following methods. Concrete renderers must override them:

• polyListFactory(plist: PolyList): PolyListRenderer — Creates the renderer wrapper for a polylist.
• materialFactory(material: Material): MaterialRenderer — Creates the renderer wrapper for a material.
• textureFactory(texture: Texture): TextureRenderer — Creates a texture renderer wrapper.
• renderBufferFactory(): RenderBuffer — Creates a render buffer.
• skySphereFactory(): SkySphere / skyCubeFactory(): SkyCube — Creates sky geometry instances.
• pipelineFactory(): Pipeline — Creates a new pipeline.
• sceneRendererFactory(): SceneRenderer — Creates the scene renderer.
• shadowRendererFactory(): ShadowRenderer — Creates a shadow renderer.