fireball/lib/geometries/TorusGeometry.js

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2018-12-25 13:59:22 +00:00
/**
* @author oosmoxiecode
* @author mrdoob / http://mrdoob.com/
* @author Mugen87 / https://github.com/Mugen87
*/
import { Geometry } from '../core/Geometry.js';
import { BufferGeometry } from '../core/BufferGeometry.js';
import { Float32BufferAttribute } from '../core/BufferAttribute.js';
import { Vector3 } from '../math/Vector3.js';
// TorusGeometry
function TorusGeometry( radius, tube, radialSegments, tubularSegments, arc ) {
Geometry.call( this );
this.type = 'TorusGeometry';
this.parameters = {
radius: radius,
tube: tube,
radialSegments: radialSegments,
tubularSegments: tubularSegments,
arc: arc
};
this.fromBufferGeometry( new TorusBufferGeometry( radius, tube, radialSegments, tubularSegments, arc ) );
this.mergeVertices();
}
TorusGeometry.prototype = Object.create( Geometry.prototype );
TorusGeometry.prototype.constructor = TorusGeometry;
// TorusBufferGeometry
function TorusBufferGeometry( radius, tube, radialSegments, tubularSegments, arc ) {
BufferGeometry.call( this );
this.type = 'TorusBufferGeometry';
this.parameters = {
radius: radius,
tube: tube,
radialSegments: radialSegments,
tubularSegments: tubularSegments,
arc: arc
};
radius = radius || 1;
tube = tube || 0.4;
radialSegments = Math.floor( radialSegments ) || 8;
tubularSegments = Math.floor( tubularSegments ) || 6;
arc = arc || Math.PI * 2;
// buffers
var indices = [];
var vertices = [];
var normals = [];
var uvs = [];
// helper variables
var center = new Vector3();
var vertex = new Vector3();
var normal = new Vector3();
var j, i;
// generate vertices, normals and uvs
for ( j = 0; j <= radialSegments; j ++ ) {
for ( i = 0; i <= tubularSegments; i ++ ) {
var u = i / tubularSegments * arc;
var 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 ( j = 1; j <= radialSegments; j ++ ) {
for ( i = 1; i <= tubularSegments; i ++ ) {
// indices
var a = ( tubularSegments + 1 ) * j + i - 1;
var b = ( tubularSegments + 1 ) * ( j - 1 ) + i - 1;
var c = ( tubularSegments + 1 ) * ( j - 1 ) + i;
var d = ( tubularSegments + 1 ) * j + i;
// faces
indices.push( a, b, d );
indices.push( b, c, d );
}
}
// build geometry
this.setIndex( indices );
this.addAttribute( 'position', new Float32BufferAttribute( vertices, 3 ) );
this.addAttribute( 'normal', new Float32BufferAttribute( normals, 3 ) );
this.addAttribute( 'uv', new Float32BufferAttribute( uvs, 2 ) );
}
TorusBufferGeometry.prototype = Object.create( BufferGeometry.prototype );
TorusBufferGeometry.prototype.constructor = TorusBufferGeometry;
export { TorusGeometry, TorusBufferGeometry };