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Comment by pixelpoet | Hacker News Reader

I'd rather just directly raycast against a nicely compressed hierarchical representation than create horrendous amounts of triangle geometry and rasterise that. The code would be absolutely tiny, and not mostly a bunch of calls into someone else's code.

But, you know, gotta do the OpenGL / DirectX / whatever vanilla API thing... that's what graphics programming is, isn't it...

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Would you happen to have a sample / example of this technique? I'd like to explore it.

It's just normal old raycasting through a voxel grid a la Amanatides and Woo: http://www.cse.yorku.ca/~amana/research/grid.pdf https://github.com/cgyurgyik/fast-voxel-traversal-algorithm/...

Casting the rays from the camera will be nice and coherent, plus you probably get much better and easier shadowing using ray casts compared to shadow maps.

How does it handle dynamic scenes? The work by the OP looked like it took an update to the VAO/VBO if the chunk changed. What's the cost of rebuilding the acceleration structure here if the scene is updated?

That's the future but raycasting currently has some major drawbacks... namely that everything looks like a noisy mess when you look around.

Curious if anyone has plotted GPU compute increases against display resolution + update frequency increases? When do the two lines cross?

I'm fairly certain that pixelpoet is referring to direct raycasting, not raytracing (light transport simulations). These aren't noisy.

I got nice and downvoted for it too, serves me right.

The noisy / Monte Carlo one is path tracing (which I've been doing since age 15 or something and commercially for over a decade), and that's indeed not what I meant but I guess all the expert gfxcoders at HN have done the efficiency analysis versus rasterisation.

Meh, I always have to remind myself how bad it is here for gfx stuff, might as well have been discussing cryptocurrency...

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