TmMolStar/src/mol-geo/primitive/icosahedron.ts

/**
 * Copyright (c) 2018 mol* contributors, licensed under MIT, See LICENSE file for more info.
 *
 * @author Alexander Rose <alexander.rose@weirdbyte.de>
 */

import { createPrimitive, Primitive } from './primitive';
import { Cage, createCage } from './cage';

const t = (1 + Math.sqrt(5)) / 2;

const icosahedronVertices: ReadonlyArray<number> = [
    -1, t, 0,   1, t, 0,  -1, -t, 0,   1, -t, 0,
    0, -1, t,  0, 1, t,   0, -1, -t,  0, 1, -t,
    t, 0, -1,  t, 0, 1,  -t, 0, -1,  -t, 0, 1
];

const icosahedronIndices: ReadonlyArray<number> = [
    0, 11, 5,  0, 5, 1,    0, 1, 7,    0, 7, 10,  0, 10, 11,
    1, 5, 9,   5, 11, 4,  11, 10, 2,  10, 7, 6,   7, 1, 8,
    3, 9, 4,   3, 4, 2,    3, 2, 6,    3, 6, 8,   3, 8, 9,
    4, 9, 5,   2, 4, 11,   6, 2, 10,   8, 6, 7,   9, 8, 1
];

const icosahedronEdges: ReadonlyArray<number> = [
    0, 11,  5, 11,  0, 5,   1, 5,  0, 1,  1, 7,  0, 7,   7, 10,  0, 10,  10, 11,
    5, 9,   4, 11,  2, 10,  6, 7,  1, 8,  3, 9,  4, 9,   3, 4,   2, 4,   2, 3,
    2, 6,   3, 6,   6, 8,   3, 8,  8, 9,  4, 5,  2, 11,  6, 10,  7, 8,   1, 9
]

let icosahedron: Primitive
export function Icosahedron(): Primitive {
    if (!icosahedron) icosahedron = createPrimitive(icosahedronVertices, icosahedronIndices)
    return icosahedron
}

const icosahedronCage = createCage(icosahedronVertices, icosahedronEdges)
export function IcosahedronCage(): Cage {
    return icosahedronCage
}