fireball/lib/geometries/SphereGeometry.js

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2018-12-25 13:59:22 +00:00
/**
* @author mrdoob / http://mrdoob.com/
* @author benaadams / https://twitter.com/ben_a_adams
* @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';
// SphereGeometry
function SphereGeometry( radius, widthSegments, heightSegments, phiStart, phiLength, thetaStart, thetaLength ) {
Geometry.call( this );
this.type = 'SphereGeometry';
this.parameters = {
radius: radius,
widthSegments: widthSegments,
heightSegments: heightSegments,
phiStart: phiStart,
phiLength: phiLength,
thetaStart: thetaStart,
thetaLength: thetaLength
};
this.fromBufferGeometry( new SphereBufferGeometry( radius, widthSegments, heightSegments, phiStart, phiLength, thetaStart, thetaLength ) );
this.mergeVertices();
}
SphereGeometry.prototype = Object.create( Geometry.prototype );
SphereGeometry.prototype.constructor = SphereGeometry;
// SphereBufferGeometry
function SphereBufferGeometry( radius, widthSegments, heightSegments, phiStart, phiLength, thetaStart, thetaLength ) {
BufferGeometry.call( this );
this.type = 'SphereBufferGeometry';
this.parameters = {
radius: radius,
widthSegments: widthSegments,
heightSegments: heightSegments,
phiStart: phiStart,
phiLength: phiLength,
thetaStart: thetaStart,
thetaLength: thetaLength
};
radius = radius || 1;
widthSegments = Math.max( 3, Math.floor( widthSegments ) || 8 );
heightSegments = Math.max( 2, Math.floor( heightSegments ) || 6 );
phiStart = phiStart !== undefined ? phiStart : 0;
phiLength = phiLength !== undefined ? phiLength : Math.PI * 2;
thetaStart = thetaStart !== undefined ? thetaStart : 0;
thetaLength = thetaLength !== undefined ? thetaLength : Math.PI;
var thetaEnd = thetaStart + thetaLength;
var ix, iy;
var index = 0;
var grid = [];
var vertex = new Vector3();
var normal = new Vector3();
// buffers
var indices = [];
var vertices = [];
var normals = [];
var uvs = [];
// generate vertices, normals and uvs
for ( iy = 0; iy <= heightSegments; iy ++ ) {
var verticesRow = [];
var v = iy / heightSegments;
for ( ix = 0; ix <= widthSegments; ix ++ ) {
var u = ix / widthSegments;
// vertex
vertex.x = - radius * Math.cos( phiStart + u * phiLength ) * Math.sin( thetaStart + v * thetaLength );
vertex.y = radius * Math.cos( thetaStart + v * thetaLength );
vertex.z = radius * Math.sin( phiStart + u * phiLength ) * Math.sin( thetaStart + v * thetaLength );
vertices.push( vertex.x, vertex.y, vertex.z );
// normal
normal.set( vertex.x, vertex.y, vertex.z ).normalize();
normals.push( normal.x, normal.y, normal.z );
// uv
uvs.push( u, 1 - v );
verticesRow.push( index ++ );
}
grid.push( verticesRow );
}
// indices
for ( iy = 0; iy < heightSegments; iy ++ ) {
for ( ix = 0; ix < widthSegments; ix ++ ) {
var a = grid[ iy ][ ix + 1 ];
var b = grid[ iy ][ ix ];
var c = grid[ iy + 1 ][ ix ];
var d = grid[ iy + 1 ][ ix + 1 ];
if ( iy !== 0 || thetaStart > 0 ) indices.push( a, b, d );
if ( iy !== heightSegments - 1 || thetaEnd < Math.PI ) 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 ) );
}
SphereBufferGeometry.prototype = Object.create( BufferGeometry.prototype );
SphereBufferGeometry.prototype.constructor = SphereBufferGeometry;
export { SphereGeometry, SphereBufferGeometry };