molstar
Version:
A comprehensive macromolecular library.
52 lines (51 loc) • 2.25 kB
JavaScript
/**
* Copyright (c) 2019 mol* contributors, licensed under MIT, See LICENSE file for more info.
*
* @author Alexander Rose <alexander.rose@weirdbyte.de>
*/
import { createPrimitive } from './primitive';
import { dodecahedronVertices, dodecahedronFaces } from './dodecahedron';
import { Vec3 } from '../../mol-math/linear-algebra';
function calcCenter(out, ...vec3s) {
Vec3.set(out, 0, 0, 0);
for (let i = 0, il = vec3s.length; i < il; ++i) {
Vec3.add(out, out, vec3s[i]);
}
Vec3.scale(out, out, 1 / vec3s.length);
return out;
}
const center = Vec3.zero();
const dir = Vec3.zero();
const tip = Vec3.zero();
const vecA = Vec3.zero();
const vecB = Vec3.zero();
const vecC = Vec3.zero();
const vecD = Vec3.zero();
const vecE = Vec3.zero();
/**
* Create a spiked ball derived from a dodecahedron
* @param radiusRatio ratio between inner radius (dodecahedron) and outher radius (spikes)
*/
export function SpikedBall(radiusRatio = 1) {
const vertices = dodecahedronVertices.slice(0);
const indices = [];
let offset = vertices.length / 3;
for (let i = 0, il = dodecahedronFaces.length; i < il; i += 5) {
Vec3.fromArray(vecA, dodecahedronVertices, dodecahedronFaces[i] * 3);
Vec3.fromArray(vecB, dodecahedronVertices, dodecahedronFaces[i + 1] * 3);
Vec3.fromArray(vecC, dodecahedronVertices, dodecahedronFaces[i + 2] * 3);
Vec3.fromArray(vecD, dodecahedronVertices, dodecahedronFaces[i + 3] * 3);
Vec3.fromArray(vecE, dodecahedronVertices, dodecahedronFaces[i + 4] * 3);
calcCenter(center, vecA, vecB, vecC, vecD, vecE);
Vec3.triangleNormal(dir, vecA, vecB, vecC);
Vec3.scaleAndAdd(tip, center, dir, radiusRatio);
Vec3.toArray(tip, vertices, offset * 3);
indices.push(offset, dodecahedronFaces[i], dodecahedronFaces[i + 1]);
indices.push(offset, dodecahedronFaces[i + 1], dodecahedronFaces[i + 2]);
indices.push(offset, dodecahedronFaces[i + 2], dodecahedronFaces[i + 3]);
indices.push(offset, dodecahedronFaces[i + 3], dodecahedronFaces[i + 4]);
indices.push(offset, dodecahedronFaces[i + 4], dodecahedronFaces[i]);
offset += 1;
}
return createPrimitive(vertices, indices);
}