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📄 CircleGeometry.js

📊 Analysis Summary

Metric	Count
🔧 Functions	2
🧱 Classes	1
📦 Imports	4
📊 Variables & Constants	7

📚 Table of Contents

• Imports
• Variables & Constants
• Functions
• Classes

🛠️ File Location:

📂 src/geometries/CircleGeometry.js

📦 Imports

Name	Source
BufferGeometry	../core/BufferGeometry.js
Float32BufferAttribute	../core/BufferAttribute.js
Vector3	../math/Vector3.js
Vector2	../math/Vector2.js

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Variables & Constants

Name	Type	Kind	Value	Exported
indices	any[]	let/var	[]	✗
vertices	any[]	let/var	[]	✗
normals	any[]	let/var	[]	✗
uvs	any[]	let/var	[]	✗
vertex	Vector3	let/var	new Vector3()	✗
uv	Vector2	let/var	new Vector2()	✗
segment	number	let/var	thetaStart + s / segments * thetaLength	✗

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Functions

CircleGeometry.copy(source: any): this

Parameters:

• source any

Returns: this

Calls:

• super.copy
• Object.assign

Code

copy( source ) {

        super.copy( source );

        this.parameters = Object.assign( {}, source.parameters );

        return this;

    }

CircleGeometry.fromJSON(data: any): CircleGeometry

JSDoc:

/**
     * Factory method for creating an instance of this class from the given
     * JSON object.
     *
     * @param {Object} data - A JSON object representing the serialized geometry.
     * @return {CircleGeometry} A new instance.
     */

Parameters:

• data any

Returns: CircleGeometry

Code

static fromJSON( data ) {

        return new CircleGeometry( data.radius, data.segments, data.thetaStart, data.thetaLength );

    }

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Classes

CircleGeometry

Class Code

class CircleGeometry extends BufferGeometry {

    /**
     * Constructs a new circle geometry.
     *
     * @param {number} [radius=1] - Radius of the circle.
     * @param {number} [segments=32] - Number of segments (triangles), minimum = `3`.
     * @param {number} [thetaStart=0] - Start angle for first segment in radians.
     * @param {number} [thetaLength=Math.PI*2] - The central angle, often called theta,
     * of the circular sector in radians. The default value results in a complete circle.
     */
    constructor( radius = 1, segments = 32, thetaStart = 0, thetaLength = Math.PI * 2 ) {

        super();

        this.type = 'CircleGeometry';

        /**
         * Holds the constructor parameters that have been
         * used to generate the geometry. Any modification
         * after instantiation does not change the geometry.
         *
         * @type {Object}
         */
        this.parameters = {
            radius: radius,
            segments: segments,
            thetaStart: thetaStart,
            thetaLength: thetaLength
        };

        segments = Math.max( 3, segments );

        // buffers

        const indices = [];
        const vertices = [];
        const normals = [];
        const uvs = [];

        // helper variables

        const vertex = new Vector3();
        const uv = new Vector2();

        // center point

        vertices.push( 0, 0, 0 );
        normals.push( 0, 0, 1 );
        uvs.push( 0.5, 0.5 );

        for ( let s = 0, i = 3; s <= segments; s ++, i += 3 ) {

            const segment = thetaStart + s / segments * thetaLength;

            // vertex

            vertex.x = radius * Math.cos( segment );
            vertex.y = radius * Math.sin( segment );

            vertices.push( vertex.x, vertex.y, vertex.z );

            // normal

            normals.push( 0, 0, 1 );

            // uvs

            uv.x = ( vertices[ i ] / radius + 1 ) / 2;
            uv.y = ( vertices[ i + 1 ] / radius + 1 ) / 2;

            uvs.push( uv.x, uv.y );

        }

        // indices

        for ( let i = 1; i <= segments; i ++ ) {

            indices.push( i, i + 1, 0 );

        }

        // build geometry

        this.setIndex( indices );
        this.setAttribute( 'position', new Float32BufferAttribute( vertices, 3 ) );
        this.setAttribute( 'normal', new Float32BufferAttribute( normals, 3 ) );
        this.setAttribute( 'uv', new Float32BufferAttribute( uvs, 2 ) );

    }

    copy( source ) {

        super.copy( source );

        this.parameters = Object.assign( {}, source.parameters );

        return this;

    }

    /**
     * Factory method for creating an instance of this class from the given
     * JSON object.
     *
     * @param {Object} data - A JSON object representing the serialized geometry.
     * @return {CircleGeometry} A new instance.
     */
    static fromJSON( data ) {

        return new CircleGeometry( data.radius, data.segments, data.thetaStart, data.thetaLength );

    }

}

Methods

copy(source: any): this

Code

copy( source ) {

        super.copy( source );

        this.parameters = Object.assign( {}, source.parameters );

        return this;

    }

fromJSON(data: any): CircleGeometry

Code

static fromJSON( data ) {

        return new CircleGeometry( data.radius, data.segments, data.thetaStart, data.thetaLength );

    }

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