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📄 HemisphereLightHelper.js

📊 Analysis Summary

Metric	Count
🔧 Functions	2
🧱 Classes	1
📦 Imports	7
📊 Variables & Constants	7

📚 Table of Contents

• Imports
• Variables & Constants
• Functions
• Classes

🛠️ File Location:

📂 src/helpers/HemisphereLightHelper.js

📦 Imports

Name	Source
Vector3	../math/Vector3.js
Color	../math/Color.js
Object3D	../core/Object3D.js
Mesh	../objects/Mesh.js
MeshBasicMaterial	../materials/MeshBasicMaterial.js
OctahedronGeometry	../geometries/OctahedronGeometry.js
BufferAttribute	../core/BufferAttribute.js

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Variables & Constants

Name	Type	Kind	Value	Exported
_vector	Vector3	let/var	new Vector3()	✗
_color1	Color	let/var	new Color()	✗
_color2	Color	let/var	new Color()	✗
geometry	OctahedronGeometry	let/var	new OctahedronGeometry( size )	✗
colors	Float32Array<ArrayBuffer>	let/var	new Float32Array( position.count * 3 )	✗
mesh	Object3D	let/var	this.children[ 0 ]	✗
color	Color	let/var	( i < ( l / 2 ) ) ? _color1 : _color2	✗

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Functions

HemisphereLightHelper.dispose(): void

JSDoc:

/**
     * Frees the GPU-related resources allocated by this instance. Call this
     * method whenever this instance is no longer used in your app.
     */

Returns: void

Calls:

• this.children[ 0 ].geometry.dispose
• this.children[ 0 ].material.dispose

Code

dispose() {

        this.children[ 0 ].geometry.dispose();
        this.children[ 0 ].material.dispose();

    }

HemisphereLightHelper.update(): void

JSDoc:

/**
     * Updates the helper to match the position and direction of the
     * light being visualized.
     */

Returns: void

Calls:

• this.material.color.set
• mesh.geometry.getAttribute
• _color1.copy
• _color2.copy
• colors.setXYZ
• this.light.updateWorldMatrix
• mesh.lookAt
• _vector.setFromMatrixPosition( this.light.matrixWorld ).negate

Code

update() {

        const mesh = this.children[ 0 ];

        if ( this.color !== undefined ) {

            this.material.color.set( this.color );

        } else {

            const colors = mesh.geometry.getAttribute( 'color' );

            _color1.copy( this.light.color );
            _color2.copy( this.light.groundColor );

            for ( let i = 0, l = colors.count; i < l; i ++ ) {

                const color = ( i < ( l / 2 ) ) ? _color1 : _color2;

                colors.setXYZ( i, color.r, color.g, color.b );

            }

            colors.needsUpdate = true;

        }

        this.light.updateWorldMatrix( true, false );

        mesh.lookAt( _vector.setFromMatrixPosition( this.light.matrixWorld ).negate() );

    }

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Classes

HemisphereLightHelper

Class Code

class HemisphereLightHelper extends Object3D {

    /**
     * Constructs a new hemisphere light helper.
     *
     * @param {HemisphereLight} light - The light to be visualized.
     * @param {number} [size=1] - The size of the mesh used to visualize the light.
     * @param {number|Color|string} [color] - The helper's color. If not set, the helper will take
     * the color of the light.
     */
    constructor( light, size, color ) {

        super();

        /**
         * The light being visualized.
         *
         * @type {HemisphereLight}
         */
        this.light = light;

        this.matrix = light.matrixWorld;
        this.matrixAutoUpdate = false;

        /**
         * The color parameter passed in the constructor.
         * If not set, the helper will take the color of the light.
         *
         * @type {number|Color|string}
         */
        this.color = color;

        this.type = 'HemisphereLightHelper';

        const geometry = new OctahedronGeometry( size );
        geometry.rotateY( Math.PI * 0.5 );

        this.material = new MeshBasicMaterial( { wireframe: true, fog: false, toneMapped: false } );
        if ( this.color === undefined ) this.material.vertexColors = true;

        const position = geometry.getAttribute( 'position' );
        const colors = new Float32Array( position.count * 3 );

        geometry.setAttribute( 'color', new BufferAttribute( colors, 3 ) );

        this.add( new Mesh( geometry, this.material ) );

        this.update();

    }

    /**
     * Frees the GPU-related resources allocated by this instance. Call this
     * method whenever this instance is no longer used in your app.
     */
    dispose() {

        this.children[ 0 ].geometry.dispose();
        this.children[ 0 ].material.dispose();

    }

    /**
     * Updates the helper to match the position and direction of the
     * light being visualized.
     */
    update() {

        const mesh = this.children[ 0 ];

        if ( this.color !== undefined ) {

            this.material.color.set( this.color );

        } else {

            const colors = mesh.geometry.getAttribute( 'color' );

            _color1.copy( this.light.color );
            _color2.copy( this.light.groundColor );

            for ( let i = 0, l = colors.count; i < l; i ++ ) {

                const color = ( i < ( l / 2 ) ) ? _color1 : _color2;

                colors.setXYZ( i, color.r, color.g, color.b );

            }

            colors.needsUpdate = true;

        }

        this.light.updateWorldMatrix( true, false );

        mesh.lookAt( _vector.setFromMatrixPosition( this.light.matrixWorld ).negate() );

    }

}

Methods

dispose(): void

Code

dispose() {

        this.children[ 0 ].geometry.dispose();
        this.children[ 0 ].material.dispose();

    }

update(): void

Code

update() {

        const mesh = this.children[ 0 ];

        if ( this.color !== undefined ) {

            this.material.color.set( this.color );

        } else {

            const colors = mesh.geometry.getAttribute( 'color' );

            _color1.copy( this.light.color );
            _color2.copy( this.light.groundColor );

            for ( let i = 0, l = colors.count; i < l; i ++ ) {

                const color = ( i < ( l / 2 ) ) ? _color1 : _color2;

                colors.setXYZ( i, color.r, color.g, color.b );

            }

            colors.needsUpdate = true;

        }

        this.light.updateWorldMatrix( true, false );

        mesh.lookAt( _vector.setFromMatrixPosition( this.light.matrixWorld ).negate() );

    }

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