//// nBody.js// examples//// Created by Philip Rosedale on March 18, 2017// Copyright 2017 High Fidelity, Inc.//// Create some spheres that obey gravity, which is great to teach physics. // You can control how many to create by changing the value of 'n' below. // Grab them and watch the others move around. // // // Distributed under the Apache License, Version 2.0.// See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html//var bodies = [];var n = 3; var radius = 0.1;var G = 0.25;var EARTH = Script.getExternalPath(Script.ExternalPaths.HF_Content, "/seth/production/NBody/earth.fbx");var MOON = Script.getExternalPath(Script.ExternalPaths.HF_Content, "/seth/production/NBody/moon.fbx");var COLOR1 = { red: 51, green: 51, blue: 255 };var COLOR2 = { red: 51, green: 51, blue: 255 };var COLOR3 = { red: 51, green: 51, blue: 255 };var inFront = Vec3.sum(Camera.getPosition(), Vec3.multiply(radius * 20, Quat.getFront(Camera.getOrientation())));for (var i = 0; i < n; i++) { bodies.push(Entities.addEntity({ type: "Model", modelURL: (i == 0) ? EARTH : MOON, shapeType: "sphere", dimensions: { x: radius * 2, y: radius * 2, z: radius * 2}, position: Vec3.sum(inFront, { x: 0, y: i * 2 * radius, z: 0 }), gravity: { x: 0, y: 0, z: 0 }, damping: 0.0, angularDamping: 0.0, dynamic: true }));}Script.update.connect(function(dt) { var props = []; for (var i = 0; i < n; i++) { props.push(Entities.getEntityProperties(bodies[i])); } for (var i = 0; i < n; i++) { if (props[i].dynamic) { var dv = { x: 0, y: 0, z: 0}; for (var j = 0; j < n; j++) { if (i != j) { dv = Vec3.sum(dv, Vec3.multiply(G * dt / Vec3.distance(props[i].position, props[j].position), Vec3.normalize(Vec3.subtract(props[j].position, props[i].position)))); } } Entities.editEntity(bodies[i], { velocity: Vec3.sum(props[i].velocity, dv)}); } } });Script.scriptEnding.connect(function scriptEnding() { for (var i = 0; i < n; i++) { Entities.deleteEntity(bodies[i]); }});
//
// nBody.js
// examples
//
// Created by Philip Rosedale on March 18, 2017
// Copyright 2017 High Fidelity, Inc.
//
// Create some spheres that obey gravity, which is great to teach physics.
// You can control how many to create by changing the value of 'n' below.
// Grab them and watch the others move around.
//
//
// Distributed under the Apache License, Version 2.0.
// See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
//
var bodies = [];
var n = 3;
var radius = 0.1;
var G = 0.25;
var EARTH = Script.getExternalPath(Script.ExternalPaths.HF_Content, "/seth/production/NBody/earth.fbx");
var MOON = Script.getExternalPath(Script.ExternalPaths.HF_Content, "/seth/production/NBody/moon.fbx");
var COLOR1 = { red: 51, green: 51, blue: 255 };
var COLOR2 = { red: 51, green: 51, blue: 255 };
var COLOR3 = { red: 51, green: 51, blue: 255 };
var inFront = Vec3.sum(Camera.getPosition(), Vec3.multiply(radius * 20, Quat.getFront(Camera.getOrientation())));
for (var i = 0; i < n; i++) {
bodies.push(Entities.addEntity({
type: "Model",
modelURL: (i == 0) ? EARTH : MOON,
shapeType: "sphere",
dimensions: { x: radius * 2, y: radius * 2, z: radius * 2},
position: Vec3.sum(inFront, { x: 0, y: i * 2 * radius, z: 0 }),
gravity: { x: 0, y: 0, z: 0 },
damping: 0.0,
angularDamping: 0.0,
dynamic: true
}));
}
Script.update.connect(function(dt) {
var props = [];
for (var i = 0; i < n; i++) {
props.push(Entities.getEntityProperties(bodies[i]));
}
for (var i = 0; i < n; i++) {
if (props[i].dynamic) {
var dv = { x: 0, y: 0, z: 0};
for (var j = 0; j < n; j++) {
if (i != j) {
dv = Vec3.sum(dv, Vec3.multiply(G * dt / Vec3.distance(props[i].position, props[j].position),
Vec3.normalize(Vec3.subtract(props[j].position, props[i].position))));
}
}
Entities.editEntity(bodies[i], { velocity: Vec3.sum(props[i].velocity, dv)});
}
}
});
Script.scriptEnding.connect(function scriptEnding() {
for (var i = 0; i < n; i++) {
Entities.deleteEntity(bodies[i]);
}
});