grid-apps-cmms/src2/geo/csg.js
2025-06-14 11:11:20 -04:00

128 lines
3.7 KiB
JavaScript

/** Copyright 2014-2019 Stewart Allen -- All Rights Reserved */
"use strict";
import { base } from './base.js';
import { THREE } from '../ext/three.js';
import manifold from '../ext/manifold.js';
const { Mesh, BufferGeometry, Vector3 } = THREE;
const debug = true;
const precision = 0.001;
const factor = 1/precision;
function log() {
console.log(...arguments);
}
export const CSG = {
// accepts 2 or more arguments with threejs vertex position arrays
union() {
return CSG.moduleOp('manifold.union', 'union', ...arguments);
},
// accepts 2 or more arguments with threejs vertex position arrays
// the fist argument is the target mesh. the rest are negatives
subtract() {
return CSG.moduleOp('manifold.subtract', 'difference', ...arguments);
},
// accepts 2 or more arguments with threejs vertex position arrays
intersect() {
return CSG.moduleOp('manifold.intersect', 'intersection', ...arguments);
},
// accepts 2 or more arguments with threejs vertex position arrays
difference() {
return CSG.moduleOp('manifold.difference', 'difference', ...arguments);
},
moduleOp(name, op) {
log(`${name} ${arguments.length} meshes`);
const args = [...arguments].slice(2).map(a => new Instance.Manifold(a));
if (args.length < 2) {
throw "missing one or more meshes";
}
const result = Instance.Manifold[op](...args);
const output = result.getMesh();
const errors = [ ...args, result ].map(m => m.status().value);
for (let m of [ ...args, result ]) {
m.delete();
}
if (errors.reduce((a,b) => a+b)) {
throw `${errors}`;
}
return output;
},
toPositionArray(mesh) {
let { vertProperties, triVerts } = mesh;
let vertPos = vertProperties;
if (vertPos && triVerts) {
const vertices = new Float32Array(triVerts.length * 3);
for (let p=0, i=0, l=triVerts.length; i<l; i++) {
let vi = triVerts[i] * 3;
vertices[p++] = vertPos[vi++];
vertices[p++] = vertPos[vi++];
vertices[p++] = vertPos[vi++];
}
return vertices.map(v => v/factor);
}
throw "mesh missing required fields";
},
fromPositionArray(pos) {
const { index, vertices } = indexVertices(pos);
let mesh = new Instance.Mesh({
vertProperties: vertices.map(v => (v*factor)|0).toFloat32(),
triVerts: index.toUint32()
});
return mesh;
},
toBox3(mesh) {
const { min, max } = mesh._boundingBox();
const vmin = new THREE.Vector3(min.x, min.y, min.z);
const vmax = new THREE.Vector3(max.x, max.y, max.z);
return new THREE.Box3(vmin, vmax);
},
indexVertices
};
function indexVertices(pos) {
log(`indexing ${pos.length/3} vertices`);
let ipos = 0;
const index = [];
const vertices = [];
const cache = {};
const temp = { x: 0, y: 0, z: 0 };
for (let i=0, length = pos.length; i<length; ) {
temp.x = pos[i++];
temp.y = pos[i++];
temp.z = pos[i++];
let key = [
((temp.x * 100000) | 0),
((temp.y * 100000) | 0),
((temp.z * 100000) | 0)
].join('');
let ip = cache[key];
if (ip >= 0) {
index.push(ip);
} else {
index.push(ipos);
cache[key] = (ipos++);
vertices.push(temp.x, temp.y, temp.z);
}
}
return { index, vertices };
}
let Instance;
manifold({
locateFile() { return "/wasm/manifold.wasm" }
}).then(inst => {
inst.setup();
Instance = inst;
CSG.Instance = () => { return Instance };
});