可以帮我修改成threejs v01420版本接受的代码吗 const particleCount = 1000; const particles = new ThreeGeometry; for let p = 0; p particleCount; p++ const particle = new ThreeVector3 Mathra

const particleCount = 1000; const particles = new THREE.Geometry();

  for (let p = 0; p < particleCount; p++) {
    const particle = new THREE.Vector3(
      Math.random() * 50 - 25,
      Math.random() * 50 - 25,
      Math.random() * 50 - 25);
    particles.vertices.push(particle);
  }

  const particleMaterial = new THREE.PointsMaterial({
    color: 0xff3300,
    size: 1,
    blending: THREE.AdditiveBlending,
    transparent: true,
    opacity: 0.8
  });

  const particleSystem = new THREE.Points(particles, particleMaterial);
  const velocity = new THREE.Vector3(0, 0.5, 0);
  scene.add(particleSystem);
  function animateFire() {
    for (let i = 0; i < particleCount; i++) {
      const particle = particleSystem.geometry.vertices[i];
      particle.add(velocity);
      if (particle.y > 25) {
        particle.y = Math.random() * -10;
        particle.x = Math.random() * 50 - 25;
        particle.z = Math.random() * 50 - 25;
      }
    }
    particleSystem.geometry.verticesNeedUpdate = true;
  }