// Author: Daniel Kaye

//  URL: http://dnkaye.com/2020_CodingChallenges.html

//

// Based on Daniel Schiffman's (Coding Train) coding challenges

//  URL: https://thecodingtrain.com/CodingChallenges/009-solarsystemgenerator3d-texture

//  

// What is this?

//  Attempt to add 3d textures to the planets of my previously created 3d solar system

//

// How do I do this?

//  I attempt to complete Daniel Schiffman's coding challenges before watching

//  his video, then afterwards I watch and see what he did differently, and learn!

//

// Things I'm proud of / differences from The Coding Train version:

// not much - never used textures with p5.js before, but it was so easy - just load an image and use the 'texture' function instead of the 'fill' function

//  had to make each planet rotate aroudn a random axis now that they have textures

​

let speed = 0.002;

let lightColor;

let lightLocation;

​

let sunRadius = 20;

let sunAngleX = 0;

let sunAngleY = 0;

let sunAngleZ = 0;

let planets = [];

let numOfPlanets = 6;

let minPlanetRadius = 3;

let maxPlanetRadius = 15;

let stars = [];

let numOfStars = 200;

​

let sunTexture;

let earthTexture;

let textureImages = [];

let numOfPlanetTextures = 7;

let fontArial;

​

function preload() {

  sunTexture = loadImage('texture_sun.png');

  earthTexture = loadImage('texture_earth.jpg');

  for (let i = 0; i < numOfPlanetTextures; i++) {

    textureImages.push(loadImage('texture_planet_' + i + '.jpg'));

  }

  fontArial = loadFont('ARIAL.TTF');

}

​

function setup() {

  createCanvas(400, 400, WEBGL);

  createLights();

  createPlanets();

  createStars();

  textureImages.push(earthTexture);

  textFont(fontArial);

}

​

function draw() {

  if (focused || frameCount < 30) {

    background(0);

    // drawStars();  // seems to crash program? Just draws 200 points...?

    push();

    locateCamera();

    drawLights();

    drawSun();

    drawOrbits();

    drawPlanets();

    pop();

  } else {

    drawUnpauseInstructions();

  }

}

​

function drawUnpauseInstructions() {

  noStroke();

  fill(255);

  textAlign(CENTER);

  textSize(18);

  text('click to activate', 0, height / 2 - height / 5);

}

​

function locateCamera() {

  translate(0, -height / 8, 0);

  rotateX(PI * 0.3);

}

​

function createLights() {

  lightColor = color(255);

  lightLocation = createVector(width, height, -100);

}

​

function drawLights() {

  ambientLight(100);

  directionalLight(lightColor, lightLocation);

}

​

function createPlanets() {

  for (let i = 0; i < numOfPlanets; i++) {

    planets.push(new Planet());

  }

}

​

function drawPlanets() {

  for (let planet of planets) {

    planet.drawPlanet();

  }

}

​

function drawOrbits() {

  for (let planet of planets) {

    planet.drawOrbit();

  }

}

​

function drawSun() {

  noStroke();

  texture(sunTexture);

  push();

  rotateX(sunAngleX);

  rotateY(sunAngleY);

  rotateZ(sunAngleZ);

  sphere(sunRadius);

  pop();

  sunAngleX += speed;

  sunAngleY += speed;

  sunAngleZ += speed;

}

​

function createStars() {

  for (let i = 0; i < numOfStars; i++) {

    let point = [];

    point[0] = random(-width / 2, width / 2);

    point[1] = random(-height / 2, height / 2);

    stars.push(point);

  }

}

​

function drawStars() {

  stroke(255, 125);

  strokeWeight(0.25);

  for (let arr of stars) {

    point(arr[0], arr[1]);

  }

}

​

function isHovered() {

  if (mouseX > 0 && mouseX < width && mouseY > 0 && mouseY < height) {

    return true;

  } else {

    return false;

  }

}