ShadowRenderer

The ShadowRenderer class handles shadow map rendering. It creates a texture render target that captures depth from the light’s perspective, used for shadow mapping in rendered scenes.

Constructor

constructor(renderer: Renderer)

Creates a renderer with default shadow map render distance (100 units) and debug mode disabled.

Properties

renderer

Returns the owning Renderer instance.

size : Vec

Current shadow map resolution (e.g., 1024x1024). Returns a Vec(0, 0) if not created yet.

shadowMapRenderDistance : number

Distance from the light’s target point where the shadow map viewport extends. Controls how far shadows are cast (default: 100 units).

debug : boolean

Enables or disables debug visualization (spheres and arrows showing camera/light positions).

depthTexture : Texture | null

Exposes the shadow map’s depth texture. Set via shadowRenderer.depthTexture = ... (used internally by the render queue to pass depth info to shaders).

Methods

create(size?: Vec): Promise<void>

Creates the shadow map render buffer with the given dimensions.

await shadowRenderer.create(new Vec(1024, 1024));  // Default size
await shadowRenderer.create(new Vec(512, 512));     // Smaller for performance

Internally:

• Creates a color texture (ShadowMap_WxH) for the light’s shadow map
• Creates a depth texture (ShadowMapDepth_WxH) via DEPTH_ATTACHMENT
• Renders the scene from the light’s perspective to generate shadows
• Stores results in _texture and _depthTexture

setShadowMapRenderDistance(distance: number)

Sets how far the shadow map extends in world units before clipping happens.

setDebug(enabled: boolean)

Toggles debug visualization mode showing camera/light positions and directions.

getLightTransform(camera, light): Mat4

Computes the light’s world transform matrix for shadow mapping. The camera and light must be Nodes or provide Camera/LightComponent:

const transform = shadowRenderer.getLightTransform(skyPlane, camera);  // Works for Node inputs

update(camera, lightComponent, renderQueue): void

Updates the shadow map from the current light position. Renders scene with the depth shader to generate the shadow texture, then sets it on the light component for use:

shadowRenderer.update(cam, skyPlane.component.lightComponent, scene.renderQueue);

Sets:

• lightComponent.depthTexture = shadow map depth texture
• lightComponent.viewMatrix = inverted light transform

Typical Usage Pattern

const shadowRenderer = new ShadowRenderer(renderer);
await shadowRenderer.create(new Vec(1024, 1024));

// In the render loop:
shadowRenderer.update(camera, lightComponent, scene.renderQueue);