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@ianjsikes
Last active May 2, 2017 15:33
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// Basic setup for a p5.js sketch
// This function gets called once at the start of the page load
function setup() {
// This creates an 800x800 HTML canvas element
createCanvas(800, 800);
}
// This function gets called ~60 times/second
function draw() {
// Paint the background white
background(255);
}
// Declare a variable called planetArray
let planetArray;
function setup() {
createCanvas(800, 800);
// Initialize that variable to an empty array
planetArray = [];
}
function draw() {
background(255);
}
let planetArray;
// Make a Planet class. This will allow us to create planet objects that share certain common behaviors
class Planet {
// Create a planet by giving it a location and mass
constructor(x, y, mass) {
// Store the location as a vector (think of it as a 2D point)
this.location = createVector(x, y);
this.mass = mass;
}
// We will call this render function in draw()
render() {
// This p5.js function draws an ellipse to the screen at the given x, y, and radius
ellipse(this.location.x, this.location.y, this.mass);
}
}
function setup() {
createCanvas(800, 800);
planetArray = [];
}
function draw() {
background(255);
// Loop over each planet in the array
for (let i = 0; i < planetArray.length; i++) {
// Call the planet's render method so it will appear on the page
planetArray[i].render();
}
}
let planetArray;
class Planet {
constructor(x, y, mass) {
this.location = createVector(x, y);
this.mass = mass;
}
render() {
ellipse(this.location.x, this.location.y, this.mass);
}
}
function setup() {
createCanvas(800, 800);
planetArray = [];
}
function draw() {
background(255);
for (let i = 0; i < planetArray.length; i++) {
planetArray[i].render();
}
}
// This p5.js function will be called every time the mouse is clicked
function mousePressed() {
// Create a new planet at the mouse's location with a random mass
let p = new Planet(mouseX, mouseY, random(50));
// Add our new planet to the array
planetArray.push(p);
}
let planetArray;
class Planet {
constructor(x, y, mass) {
this.location = createVector(x, y);
// Create vectors for velocity and acceleration
this.velocity = createVector(0, 0);
this.acceleration = createVector(0, 0);
this.mass = mass;
}
// Add a force to this planet. The force will affect the planet's
// acceleration proportional to it's mass
applyForce(force) {
// Using the classic equation Force = Mass * Acceleration
// Rewrite as Acceleration = Force / Mass
// Add that acceleration to our planet's acceleration
this.acceleration.add(force.div(this.mass));
}
render() {
ellipse(this.location.x, this.location.y, this.mass);
// Add acceleration to velocity, velocity to location
this.velocity.add(this.acceleration);
this.location.add(this.velocity);
this.acceleration.mult(0);
}
}
function setup() {
createCanvas(800, 800);
planetArray = [];
}
function draw() {
background(255);
for (let i = 0; i < planetArray.length; i++) {
planetArray[i].render();
}
}
function mousePressed() {
let p = new Planet(mouseX, mouseY, random(50));
planetArray.push(p);
}
let planetArray;
class Planet {
constructor(x, y, mass) {
this.location = createVector(x, y);
this.velocity = createVector(0, 0);
this.acceleration = createVector(0, 0);
this.mass = mass;
}
applyForce(force) {
this.acceleration.add(force.div(this.mass));
}
// This function takes another planet and applies a force towards this planet
attract(other) {
// Create a vector from this planet to the other
const attraction = p5.Vector.sub(this.location, other.location);
// Only attract the other planet if it is not touching this planet
if (attraction.mag() > this.mass + other.mass) {
// Create a force according to Newton's Law of Gravitation: F = (G*m*M) / (r*r)
const force = (this.mass * other.mass) / attraction.magSq();
// Create a normalized vector towards the other planet
attraction.normalize();
// Multiply it by the force
attraction.mult(force);
// Apply the gravitational force
other.applyForce(attraction);
}
}
render() {
ellipse(this.location.x, this.location.y, this.mass);
this.velocity.add(this.acceleration);
this.location.add(this.velocity);
this.acceleration.mult(0);
}
}
function setup() {
createCanvas(800, 800);
planetArray = [];
}
function draw() {
background(255);
for (let i = 0; i < planetArray.length; i++) {
planetArray[i].render();
// Each planet loops over all the other planets and attracts them
for (let j = 0; j < planetArray.length; j++) {
if (i !== j) {
planetArray[i].attract(planetArray[j]);
}
}
}
}
function mousePressed() {
let p = new Planet(mouseX, mouseY, random(50));
planetArray.push(p);
}
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