molstar
Version:
A comprehensive macromolecular library.
106 lines (105 loc) • 4.03 kB
JavaScript
;
/**
* Copyright (c) 2018-2020 mol* contributors, licensed under MIT, See LICENSE file for more info.
*
* @author Alexander Rose <alexander.rose@weirdbyte.de>
*/
Object.defineProperty(exports, "__esModule", { value: true });
exports.DefaultPolyhedronProps = void 0;
exports.Polyhedron = Polyhedron;
// adapted from three.js, MIT License Copyright 2010-2018 three.js authors
const linear_algebra_1 = require("../../mol-math/linear-algebra");
const util_1 = require("../util");
exports.DefaultPolyhedronProps = {
radius: 1,
detail: 0
};
function Polyhedron(_vertices, _indices, props) {
const { radius, detail } = { ...exports.DefaultPolyhedronProps, ...props };
const builder = createBuilder();
const { vertices, indices } = builder;
// the subdivision creates the vertex buffer data
subdivide(detail);
// all vertices should lie on a conceptual sphere with a given radius
(0, util_1.appplyRadius)(vertices, radius);
const normals = new Float32Array(vertices.length);
(0, util_1.computeIndexedVertexNormals)(vertices, indices, normals, vertices.length / 3, indices.length / 3);
return {
vertices: new Float32Array(vertices),
normals: new Float32Array(normals),
indices: new Uint32Array(indices)
};
// helper functions
function subdivide(detail) {
const a = (0, linear_algebra_1.Vec3)();
const b = (0, linear_algebra_1.Vec3)();
const c = (0, linear_algebra_1.Vec3)();
// iterate over all faces and apply a subdivison with the given detail value
for (let i = 0; i < _indices.length; i += 3) {
// get the vertices of the face
linear_algebra_1.Vec3.fromArray(a, _vertices, _indices[i + 0] * 3);
linear_algebra_1.Vec3.fromArray(b, _vertices, _indices[i + 1] * 3);
linear_algebra_1.Vec3.fromArray(c, _vertices, _indices[i + 2] * 3);
// perform subdivision
subdivideFace(a, b, c, detail);
}
}
function subdivideFace(a, b, c, detail) {
const cols = Math.pow(2, detail);
// we use this multidimensional array as a data structure for creating the subdivision
const v = [];
// construct all of the vertices for this subdivision
for (let i = 0; i <= cols; ++i) {
v[i] = [];
const aj = (0, linear_algebra_1.Vec3)();
linear_algebra_1.Vec3.lerp(aj, a, c, i / cols);
const bj = (0, linear_algebra_1.Vec3)();
linear_algebra_1.Vec3.lerp(bj, b, c, i / cols);
const rows = cols - i;
for (let j = 0; j <= rows; ++j) {
if (j === 0 && i === cols) {
v[i][j] = aj;
}
else {
const abj = (0, linear_algebra_1.Vec3)();
linear_algebra_1.Vec3.lerp(abj, aj, bj, j / rows);
v[i][j] = abj;
}
}
}
// construct all of the faces
for (let i = 0; i < cols; ++i) {
for (let j = 0; j < 2 * (cols - i) - 1; ++j) {
const k = Math.floor(j / 2);
if (j % 2 === 0) {
builder.add(v[i][k + 1], v[i + 1][k], v[i][k]);
}
else {
builder.add(v[i][k + 1], v[i + 1][k + 1], v[i + 1][k]);
}
}
}
}
}
function createBuilder() {
const vertices = [];
const indices = [];
const vertexMap = new Map();
function addVertex(v) {
const key = `${v[0].toFixed(5)}|${v[1].toFixed(5)}|${v[2].toFixed(5)}`;
let idx = vertexMap.get(key);
if (idx === undefined) {
idx = vertices.length / 3;
vertexMap.set(key, idx);
vertices.push(...v);
}
return idx;
}
return {
vertices,
indices,
add: (v1, v2, v3) => {
indices.push(addVertex(v1), addVertex(v2), addVertex(v3));
}
};
}