Points

• Build a BufferGeometry with setAttribute('position', ...) and optionally a color attribute.
• sizeAttenuation true makes points shrink with distance; false keeps fixed pixel size.
• raycast() uses Raycaster.params.Points.threshold for hit detection.

const positions = new Float32Array(points.length * 3);
const colors = new Float32Array(points.length * 3);
const color = new THREE.Color();

points.forEach(function (p, i) {
  positions[i * 3] = p.x;
  positions[i * 3 + 1] = p.y;
  positions[i * 3 + 2] = p.z;

  color.setHSL(0.6 - p.height * 0.002, 0.55, 0.55);
  colors[i * 3] = color.r;
  colors[i * 3 + 1] = color.g;
  colors[i * 3 + 2] = color.b;
});

const geometry = new THREE.BufferGeometry();
geometry.setAttribute('position', new THREE.BufferAttribute(positions, 3));
geometry.setAttribute('color', new THREE.BufferAttribute(colors, 3));

const material = new THREE.PointsMaterial({
  size: 2,
  sizeAttenuation: false,
  vertexColors: true,
  transparent: true,
  opacity: 0.85,
  depthWrite: false
});

const cloud = new THREE.Points(geometry, material);
cloud.frustumCulled = false;   // 包围盒尚未计算时避免整体被剔除
scene.add(cloud);

• Points cannot rotate or scale individually; use Sprite or instanced quads for oriented icons.
• Dense point clouds often need depthWrite false and alphaTest to sort correctly.