File size: 3,129 Bytes
b797337 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 | import { BufferGeometry } from '../core/BufferGeometry.js';
import { Float32BufferAttribute } from '../core/BufferAttribute.js';
import { Vector3 } from '../math/Vector3.js';
class SphereGeometry extends BufferGeometry {
constructor( radius = 1, widthSegments = 32, heightSegments = 16, phiStart = 0, phiLength = Math.PI * 2, thetaStart = 0, thetaLength = Math.PI ) {
super();
this.type = 'SphereGeometry';
this.parameters = {
radius: radius,
widthSegments: widthSegments,
heightSegments: heightSegments,
phiStart: phiStart,
phiLength: phiLength,
thetaStart: thetaStart,
thetaLength: thetaLength
};
widthSegments = Math.max( 3, Math.floor( widthSegments ) );
heightSegments = Math.max( 2, Math.floor( heightSegments ) );
const thetaEnd = Math.min( thetaStart + thetaLength, Math.PI );
let index = 0;
const grid = [];
const vertex = new Vector3();
const normal = new Vector3();
// buffers
const indices = [];
const vertices = [];
const normals = [];
const uvs = [];
// generate vertices, normals and uvs
for ( let iy = 0; iy <= heightSegments; iy ++ ) {
const verticesRow = [];
const v = iy / heightSegments;
// special case for the poles
let uOffset = 0;
if ( iy === 0 && thetaStart === 0 ) {
uOffset = 0.5 / widthSegments;
} else if ( iy === heightSegments && thetaEnd === Math.PI ) {
uOffset = - 0.5 / widthSegments;
}
for ( let ix = 0; ix <= widthSegments; ix ++ ) {
const 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.copy( vertex ).normalize();
normals.push( normal.x, normal.y, normal.z );
// uv
uvs.push( u + uOffset, 1 - v );
verticesRow.push( index ++ );
}
grid.push( verticesRow );
}
// indices
for ( let iy = 0; iy < heightSegments; iy ++ ) {
for ( let ix = 0; ix < widthSegments; ix ++ ) {
const a = grid[ iy ][ ix + 1 ];
const b = grid[ iy ][ ix ];
const c = grid[ iy + 1 ][ ix ];
const 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.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 SphereGeometry( data.radius, data.widthSegments, data.heightSegments, data.phiStart, data.phiLength, data.thetaStart, data.thetaLength );
}
}
export { SphereGeometry };
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