Most efficient way to place many points in a BufferGeometry – all at once or staggered?

Questions
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Hi everyone :slight_smile:

So, I realised thanks to the answers in my previous thread that I need to create a BufferGeometry with a lot of points and then just increase the draw range if I want to make points appear progressively. That’s all good.

Now I’m wondering, should I place all of them initially or should I position them progressively as I need more?

To give you some context, the geometry is a large star field that takes up the whole screen, and doesn’t scale with the window (so if you have a tiny window you’ll only see a tiny portion of it).
I’m wondering if I should create all of it on initialisation or use a window resize event to know when more of the stars become visible and position them at that moment.

I guess you should also phrase it this way: is a geometry with 10,000 vertices equivalent to one that’s only 100 vertices, performance-wise, if only 100 are visible in both cases?

This is probably a noobish question and I might have misunderstood some core concepts, sorry about that – bear with me as I understand more of how three.js works :blush:

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It does not matter what kind of data are in your buffer. The same amount of memory is allocated either way. You can easily check this by creating a typed array with a particular size. The respective buffer is completely initialized with default values (e.g. zeros). The drawRange determines how much of this data are actually processed by the WebGL graphics pipeline.

2 Likes
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Ah, right. I guess that means I’ll have to rewrite stuff… :sob:

Oh well – I’ll probably end up with a leaner solution. Thanks!