processing爱心粒子的代码

以下是processing实现爱心粒子效果的代码：

ArrayList<Particle> particles = new ArrayList<Particle>();
float pulsateMult = 0;

void setup() {
  size(600, 600, P3D);
  for (int i = 0; i < 100; i++) {
    particles.add(new Particle());
  }
}

void draw() {
  background(0);
  translate(width/2, height/2);
  for (Particle particle : particles) {
    particle.update();
    particle.display();
  }
}

class Particle {
  PVector pos;
  PVector vel;
  float zDepth;
  float size;

  Particle() {
    pos = new PVector(random(-width/2, width/2), random(-height/2, height/2), random(-width/2, width/2));
    vel = new PVector(0, 0, 0);
    zDepth = map(pos.z, -width/2, width/2, 1, 0);
    size = map(zDepth, 0, 1, 10, 2);
  }

  void update() {
    PVector dir = new PVector(-width / 2, -height / 2, 0);
    dir.add(pos);
    dir.normalize();
    dir.mult(pulsateMult * zDepth * 0.05 + cos(frameCount * 0.05) * 1.5);
    pos.add(dir);
  }

  void display() {
    pushMatrix();
    translate(pos.x, pos.y, pos.z);
    noStroke();
    fill(255, 0, 0);
    ellipse(0, 0, size, size);
    popMatrix();
  }
}