I want to implement a particle, Below is my code

    const geometry = new THREE.BufferGeometry();
    const material = new THREE.PointsMaterial({
        size: 2,
        transparent: true,
        depthWrite: false,
        vertexColors: true,
        blending: THREE.AdditiveBlending,
        map: new THREE.TextureLoader().load(getImageFile('dot2.png')),
    }); 
    const system = new Particles();
    const { position, color } = system.getInfo();
    geometry.attributes.position = position;
    geometry.attributes.color = color;

    const particles = new THREE.Points(geometry, material);
    const animate = (timestamp: number) => {
        const { position, color, opacity } = system.animateAndInfo(timestamp);
        geometry.attributes.position = position;
        geometry.attributes.color = color;
        geometry.attributes.opacity = opacity;
        requestAnimationFrame(animate);
    }
    requestAnimationFrame(animate);
    scene.add(particles);

export default class Particles {
    ...
    animate(timestamp: number) {
        if (this.state === 'SUSPEND') return;
        if (!this.timestamp) this.timestamp = timestamp;
        const deltaTime = timestamp - this.lastTimestamp;
        this.lastTimestamp = timestamp;
        this.pointList.forEach(point => point.update(timestamp, deltaTime));
        this.clearPoint();
        this.addFloatUpPoint(timestamp);
    }
    getInfo() {
        const position = this.pointList.reduce((p, c) => [...p, ...c.getPosition()], []);
        const color = this.pointList.reduce((p, c) => {
            const color = new THREE.Color(c.color);
            return [...p, ...[color.r, color.g, color.b]];
        }, [])
        const opacity = this.pointList.length < 1 ? [] : [1, ...new Array(this.pointList.length - 1).fill(0)];
        return { 
            position: new THREE.Float32BufferAttribute(position, 3), 
            color: new THREE.Float32BufferAttribute(color, 3),
            opacity: new THREE.Float32BufferAttribute(new Float32Array(opacity), 1),
        }
    }
    animateAndInfo(timestamp: number) {
        this.animate(timestamp);
        return this.getInfo();
    }
}

When I try to control the transparency of some points， it doesn’t work.

How to change part of point’s opactity in three.js BufferGeometry? Or is there any other way to achieve it?