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src/lights/AmbientLight.js

@@ -1,11 +1,36 @@
 import { Light } from './Light.js';
 
+/**
+ * This light globally illuminates all objects in the scene equally.
+ *
+ * It cannot be used to cast shadows as it does not have a direction.
+ *
+ * ```js
+ * const light = new THREE.AmbientLight( 0x404040 ); // soft white light
+ * scene.add( light );
+ * ```
+ *
+ * @augments Light
+ */
 class AmbientLight extends Light {
 
+	/**
+	 * Constructs a new ambient light.
+	 *
+	 * @param {(number|Color|string)} [color=0xffffff] - The light's color.
+	 * @param {number} [intensity=1] - The light's strength/intensity.
+	 */
 	constructor( color, intensity ) {
 
 		super( color, intensity );
 
+		/**
+		 * This flag can be used for type testing.
+		 *
+		 * @type {boolean}
+		 * @readonly
+		 * @default true
+		 */
 		this.isAmbientLight = true;
 
 		this.type = 'AmbientLight';

src/lights/DirectionalLight.js

@@ -2,21 +2,78 @@ import { Light } from './Light.js';
 import { DirectionalLightShadow } from './DirectionalLightShadow.js';
 import { Object3D } from '../core/Object3D.js';
 
+/**
+ * A light that gets emitted in a specific direction. This light will behave
+ * as though it is infinitely far away and the rays produced from it are all
+ * parallel. The common use case for this is to simulate daylight; the sun is
+ * far enough away that its position can be considered to be infinite, and
+ * all light rays coming from it are parallel.
+ *
+ * A common point of confusion for directional lights is that setting the
+ * rotation has no effect. This is because three.js's DirectionalLight is the
+ * equivalent to what is often called a 'Target Direct Light' in other
+ * applications.
+ *
+ * This means that its direction is calculated as pointing from the light's
+ * {@link Object3D#position} to the {@link DirectionalLight#target} position
+ * (as opposed to a 'Free Direct Light' that just has a rotation
+ * component).
+ *
+ * This light can cast shadows - see the {@link DirectionalLightShadow} for details.
+ *
+ * ```js
+ * // White directional light at half intensity shining from the top.
+ * const directionalLight = new THREE.DirectionalLight( 0xffffff, 0.5 );
+ * scene.add( directionalLight );
+ * ```
+ *
+ * @augments Light
+ */
 class DirectionalLight extends Light {
 
+	/**
+	 * Constructs a new directional light.
+	 *
+	 * @param {(number|Color|string)} [color=0xffffff] - The light's color.
+	 * @param {number} [intensity=1] - The light's strength/intensity.
+	 */
 	constructor( color, intensity ) {
 
 		super( color, intensity );
 
+		/**
+		 * This flag can be used for type testing.
+		 *
+		 * @type {boolean}
+		 * @readonly
+		 * @default true
+		 */
 		this.isDirectionalLight = true;
 
 		this.type = 'DirectionalLight';
 
 		this.position.copy( Object3D.DEFAULT_UP );
 		this.updateMatrix();
 
+		/**
+		 * The directional light points from its position to the
+		 * target's position.
+		 *
+		 * For the target's position to be changed to anything other
+		 * than the default, it must be added to the scene.
+		 *
+		 * It is also possible to set the target to be another 3D object
+		 * in the scene. The light will now track the target object.
+		 *
+		 * @type {Object3D}
+		 */
 		this.target = new Object3D();
 
+		/**
+		 * This property holds the light's shadow configuration.
+		 *
+		 * @type {DirectionalLightShadow}
+		 */
 		this.shadow = new DirectionalLightShadow();
 
 	}

src/lights/DirectionalLightShadow.js

@@ -1,12 +1,27 @@
 import { LightShadow } from './LightShadow.js';
 import { OrthographicCamera } from '../cameras/OrthographicCamera.js';
 
+/**
+ * Represents the shadow configuration of directional lights.
+ *
+ * @augments LightShadow
+ */
 class DirectionalLightShadow extends LightShadow {
 
+	/**
+	 * Constructs a new directional light shadow.
+	 */
 	constructor() {
 
 		super( new OrthographicCamera( - 5, 5, 5, - 5, 0.5, 500 ) );
 
+		/**
+		 * This flag can be used for type testing.
+		 *
+		 * @type {boolean}
+		 * @readonly
+		 * @default true
+		 */
 		this.isDirectionalLightShadow = true;
 
 	}

src/lights/HemisphereLight.js

@@ -2,19 +2,51 @@ import { Light } from './Light.js';
 import { Color } from '../math/Color.js';
 import { Object3D } from '../core/Object3D.js';
 
+/**
+ * A light source positioned directly above the scene, with color fading from
+ * the sky color to the ground color.
+ *
+ * This light cannot be used to cast shadows.
+ *
+ * ```js
+ * const light = new THREE.HemisphereLight( 0xffffbb, 0x080820, 1 );
+ * scene.add( light );
+ * ```
+ *
+ * @augments Light
+ */
 class HemisphereLight extends Light {
 
+	/**
+	 * Constructs a new hemisphere light.
+	 *
+	 * @param {(number|Color|string)} [skyColor=0xffffff] - The light's sky color.
+	 * @param {(number|Color|string)} [groundColor=0xffffff] - The light's ground color.
+	 * @param {number} [intensity=1] - The light's strength/intensity.
+	 */
 	constructor( skyColor, groundColor, intensity ) {
 
 		super( skyColor, intensity );
 
+		/**
+		 * This flag can be used for type testing.
+		 *
+		 * @type {boolean}
+		 * @readonly
+		 * @default true
+		 */
 		this.isHemisphereLight = true;
 
 		this.type = 'HemisphereLight';
 
 		this.position.copy( Object3D.DEFAULT_UP );
 		this.updateMatrix();
 
+		/**
+		 * The light's ground color.
+		 *
+		 * @type {Color}
+		 */
 		this.groundColor = new Color( groundColor );
 
 	}

src/lights/Light.js

@@ -1,21 +1,57 @@
 import { Object3D } from '../core/Object3D.js';
 import { Color } from '../math/Color.js';
 
+/**
+ * Abstract base class for lights - all other light types inherit the
+ * properties and methods described here.
+ *
+ * @abstract
+ * @augments Object3D
+ */
 class Light extends Object3D {
 
+	/**
+	 * Constructs a new light.
+	 *
+	 * @param {(number|Color|string)} [color=0xffffff] - The light's color.
+	 * @param {number} [intensity=1] - The light's strength/intensity.
+	 */
 	constructor( color, intensity = 1 ) {
 
 		super();
 
+		/**
+		 * This flag can be used for type testing.
+		 *
+		 * @type {boolean}
+		 * @readonly
+		 * @default true
+		 */
 		this.isLight = true;
 
 		this.type = 'Light';
 
+		/**
+		 * The light's color.
+		 *
+		 * @type {Color}
+		 */
 		this.color = new Color( color );
+
+		/**
+		 * The light's intensity.
+		 *
+		 * @type {number}
+		 * @default 1
+		 */
 		this.intensity = intensity;
 
 	}
 
+	/**
+	 * Frees the GPU-related resources allocated by this instance. Call this
+	 * method whenever this instance is no longer used in your app.
+	 */
 	dispose() {
 
 		// Empty here in base class; some subclasses override.

src/lights/LightProbe.js

@@ -1,14 +1,51 @@
 import { SphericalHarmonics3 } from '../math/SphericalHarmonics3.js';
 import { Light } from './Light.js';
 
+/**
+ * Light probes are an alternative way of adding light to a 3D scene. Unlike
+ * classical light sources (e.g. directional, point or spot lights), light
+ * probes do not emit light. Instead they store information about light
+ * passing through 3D space. During rendering, the light that hits a 3D
+ * object is approximated by using the data from the light probe.
+ *
+ * Light probes are usually created from (radiance) environment maps. The
+ * class {@link LightProbeGenerator} can be used to create light probes from
+ * cube textures or render targets. However, light estimation data could also
+ * be provided in other forms e.g. by WebXR. This enables the rendering of
+ * augmented reality content that reacts to real world lighting.
+ *
+ * The current probe implementation in three.js supports so-called diffuse
+ * light probes. This type of light probe is functionally equivalent to an
+ * irradiance environment map.
+ *
+ * @augments Light
+ */
 class LightProbe extends Light {
 
+	/**
+	 * Constructs a new light probe.
+	 *
+	 * @param {SphericalHarmonics3} sh - The spherical harmonics which represents encoded lighting information.
+	 * @param {number} [intensity=1] - The light's strength/intensity.
+	 */
 	constructor( sh = new SphericalHarmonics3(), intensity = 1 ) {
 
 		super( undefined, intensity );
 
+		/**
+		 * This flag can be used for type testing.
+		 *
+		 * @type {boolean}
+		 * @readonly
+		 * @default true
+		 */
 		this.isLightProbe = true;
 
+		/**
+		 * A light probe uses spherical harmonics to encode lighting information.
+		 *
+		 * @type {SphericalHarmonics3}
+		 */
 		this.sh = sh;
 
 	}
@@ -23,6 +60,12 @@ class LightProbe extends Light {
 
 	}
 
+	/**
+	 * Deserializes the light prove from the given JSON.
+	 *
+	 * @param {Object} json - The JSON holding the serialized light probe.
+	 * @return {LightProbe} A reference to this light probe.
+	 */
 	fromJSON( json ) {
 
 		this.intensity = json.intensity; // TODO: Move this bit to Light.fromJSON();