/
TorusGeometry.js
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/
TorusGeometry.js
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import { BufferGeometry } from '../core/BufferGeometry.js';
import { Float32BufferAttribute } from '../core/BufferAttribute.js';
import { Vector3 } from '../math/Vector3.js';
class TorusGeometry extends BufferGeometry {
constructor( radius = 1, tube = 0.4, radialSegments = 12, tubularSegments = 48, arc = Math.PI * 2 ) {
super();
this.type = 'TorusGeometry';
this.parameters = {
radius: radius,
tube: tube,
radialSegments: radialSegments,
tubularSegments: tubularSegments,
arc: arc
};
radialSegments = Math.floor( radialSegments );
tubularSegments = Math.floor( tubularSegments );
// buffers
const indices = [];
const vertices = [];
const normals = [];
const uvs = [];
// helper variables
const center = new Vector3();
const vertex = new Vector3();
const normal = new Vector3();
// generate vertices, normals and uvs
for ( let j = 0; j <= radialSegments; j ++ ) {
for ( let i = 0; i <= tubularSegments; i ++ ) {
const u = i / tubularSegments * arc;
const v = j / radialSegments * Math.PI * 2;
// vertex
vertex.x = ( radius + tube * Math.cos( v ) ) * Math.cos( u );
vertex.y = ( radius + tube * Math.cos( v ) ) * Math.sin( u );
vertex.z = tube * Math.sin( v );
vertices.push( vertex.x, vertex.y, vertex.z );
// normal
center.x = radius * Math.cos( u );
center.y = radius * Math.sin( u );
normal.subVectors( vertex, center ).normalize();
normals.push( normal.x, normal.y, normal.z );
// uv
uvs.push( i / tubularSegments );
uvs.push( j / radialSegments );
}
}
// generate indices
for ( let j = 1; j <= radialSegments; j ++ ) {
for ( let i = 1; i <= tubularSegments; i ++ ) {
// indices
const a = ( tubularSegments + 1 ) * j + i - 1;
const b = ( tubularSegments + 1 ) * ( j - 1 ) + i - 1;
const c = ( tubularSegments + 1 ) * ( j - 1 ) + i;
const d = ( tubularSegments + 1 ) * j + i;
// faces
indices.push( a, b, d );
indices.push( b, c, d );
}
}
// 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;
}
static fromJSON( data ) {
return new TorusGeometry( data.radius, data.tube, data.radialSegments, data.tubularSegments, data.arc );
}
}
export { TorusGeometry };