Question

遇到Three.js的一些问题。我正在尝试在渲染每个帧时在粒子系统内移动粒子。没有报告任何错误，但也没有任何移动！我从http://aerotwist.com/tutorials/creating-particles-with-three-js/的代码中获取的示例使用语法particle.position.y，但当我更改以下代码以反映该代码时，JS控制台返回Cannot set property 'y' of undefined。我非常感谢任何有关我出错的帮助或指示。

完整源代码：

        var scene, camera, renderer, particleCount = 0, particleSystem, particles;

        init();
        animate();

        function init()
        {
            scene = new THREE.Scene();
            camera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.1, 1000);
            scene.add(camera);
            camera.position.z = 5;

            renderer = new THREE.WebGLRenderer();
            renderer.setSize(window.innerWidth, window.innerHeight);
            document.body.appendChild(renderer.domElement);

            particleCount = 1800,
            particles = new THREE.Geometry();
            var pMaterial = new THREE.ParticleBasicMaterial({color: 0xFFFFFF, size: 0.5});

            for (var i = 0; i < particleCount; i++)
            {
                var pX = Math.random() * 500 - 250,
                    pY = Math.random() * 500 - 250,
                    pZ = Math.random() * 500 - 250,
                    particle = new THREE.Vector3(pX, pY, pZ);

                particles.vertices.push(particle);
            }

            particleSystem = new THREE.ParticleSystem(particles, pMaterial);
            scene.add(particleSystem);
        }

        function animate()
        {
            requestAnimationFrame(animate);
            renderer.render(scene, camera);

            var pCount = particleCount;
            while (pCount--)
            {
                var particle = particles.vertices[pCount];
                particle.y = Math.random() * 500 - 250;
                particleSystem.geometry.vertices.needsUpdate = true;
            }

        }

Answer 1

您似乎必须在创建particleSystem.sortParticles = true;后添加particleSystem。

Answer 2

我在同一个教程中遇到了完全相同的问题但是，使用ThreeJS 86，我既不需要setY()也不需要particleSystem.sortParticles = true;，而是particleSystem.geometry.verticesNeedUpdate = true;（不 particleSystem.geometry.vertices.needsUpdate = true;）。

在Three.JS粒子系统内移动单个粒子

2 个答案: