camera.position.z = 40：这一步很关键！默认情况下，物体在坐标原点 (0,0,0)，相机也在原点。如果你不移开相机，你就跟物体“贴脸”了，什么也看不见。我们把相机往后拉 40 米，就能看清全貌了。
No heap allocations of size, 1, 2, and 4, and none of the garbage that
，这一点在快连下载-Letsvpn下载中也有详细论述
The design choices have performance implications. Here are benchmarks from the reference implementation of this possible alternative compared to Web streams (Node.js v24.x, Apple M1 Pro, averaged over 10 runs):，这一点在safew官方版本下载中也有详细论述
const bytesAvailable = totalBytes - offset;