@polygonjs/polygonjs/src/core/geometry/modules/tet/utils/tetSphere.ts

node-based WebGL 3D engine https://polygonjs.com

import {Tetrahedron, TetrahedronSphere} from '../TetCommon';
import {Vector3} from 'three';
import {TetGeometry} from '../TetGeometry';
import {getCircumCenter} from './tetCenter';

export function circumSphere(
	tetGeometry: TetGeometry,
	id0: number,
	id1: number,
	id2: number,
	id3: number,
	target: TetrahedronSphere
) {
	const p0 = tetGeometry.points.get(id0);
	const p1 = tetGeometry.points.get(id1);
	const p2 = tetGeometry.points.get(id2);
	const p3 = tetGeometry.points.get(id3);
	if (!(p0 && p1 && p2 && p3)) {
		return;
	}
	getCircumCenter(p0.position, p1.position, p2.position, p3.position, target.center);
	target.radius = target.center.distanceTo(p0.position);
	return;
}

export function isPointInTetCircumSphere(tetrahedron: Tetrahedron, point: Vector3): boolean {
	return point.distanceTo(tetrahedron.sphere.center) <= tetrahedron.sphere.radius;
}