Paysage des lunes en 3d de Jonathan pour la fête colorée de fin d'année

paysage.pde

// https://paysage.xyz/playground/fcfa/programmer
// https://adventofcode.com/2019/day/12

var moons = [];

moons.push(new PVector(-6, 2, -9));
moons.push(new PVector(12, -14, -4));
moons.push(new PVector(9, 5, -6));
moons.push(new PVector(-1, -4, 9));

for(var m in moons) {
  var moon = moons[m];
  moon.vel = new PVector(0, 0, 0);
  moon.index = m;
}

var scale = 8;

void setup() {
  colorMode(HSB, 100);
}

var zoom = 500;
var viewdist = 350;
var viewangle = 0.5;

function transform(x, y, z) {
  var xr = x * cos(viewangle) + z * sin(viewangle);
  var yr = y;
  var zr = -x * sin(viewangle) + z * cos(viewangle);
  
  zr += viewdist;
  return new PVector(zoom * xr / zr, -zoom * yr / zr, zoom / zr);
}

function vertex3d(x, y, z) {
  var p = transform(x, y, z);
  vertex(p.x, p.y);
}

var gridY = -150;

void drawgrid() {
  beginShape(LINES);
  var gridWidth = 400, gridHeight = 400, gridCell = 20;
  for(var x=-gridWidth/2; x <= gridWidth/2; x += gridCell) {
    vertex3d(x, gridY, -gridHeight/2);
    vertex3d(x, gridY, gridHeight/2);
  }
  for(var z=-gridHeight/2; z <= gridHeight/2; z += gridCell) {
    vertex3d(-gridWidth/2, gridY, z);
    vertex3d(gridWidth/2, gridY, z);
  }
  endShape();
}

void draw() {
  background(0,0);

  fill(200, 80, 80);

  translate(width/2, height/2);

  stroke(105);

  var inc = .001;
  var simscale = 1;
  
  for(int m1 = 0; m1 < moons.length; m1++) {
    for(int m2 = 0; m2 < moons.length; m2++) {
      if(m1 == m2) continue;
      var moon1 = moons[m1], moon2 = moons[m2];
      if(moon1.x < moon2.x) moon1.vel.x+=inc;
      if(moon1.x > moon2.x) moon1.vel.x-=inc;
      if(moon1.y < moon2.y) moon1.vel.y+=inc;
      if(moon1.y > moon2.y) moon1.vel.y-=inc;
      if(moon1.z < moon2.z) moon1.vel.z+=inc;
      if(moon1.z > moon2.z) moon1.vel.z-=inc;
    }
  }
  
  for(var m in moons) {
    var moon = moons[m];
    moon.add(PVector.mult(moon.vel, simscale));
  }
  
  stroke(0, 0, 50);

  strokeWeight(1);

  drawgrid();
  
  var transformedMoons = moons.forEach(function(moon) {
    moon.transformed = transform(moon.x * scale, moon.y * scale, moon.z * scale);
  });

  moons.sort(function(ma, mb) {
    return ma.transformed.z - mb.transformed.z;
  });

  noStroke();
  for(var m in moons) {
    var moon = moons[m];
    var r = 30;
    var p = moon.transformed;

    pushStyle();
    stroke(0);
    strokeWeight(0);
    fill(moon.index * 20, 80, 80);
    ellipse(p.x, p.y, p.z * r, p.z * r);
    popStyle();

    fill(moon.index * 20, 70, 100);
    var specoff=r/30, specsize=0.8;
    ellipse(p.x - specoff * p.z, p.y - specoff * p.z, p.z * r * specsize, p.z * r * specsize);
    
    var p = transform(moon.x * scale, gridY, moon.z * scale);
    fill(0, 0, 60, 100);
    ellipse(p.x, p.y, p.z * r, .4*r*p.z);
  }
  
  viewangle += 0.01;
  
}