A Recursive Algorithm to Render Signed Distance Fields
50 points
3 days ago
| 3 comments
| pointersgonewild.com
| HN
linolevan
4 hours ago
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Played around with the code to implement a little bit of SIMD. Was able to squeeze out a decent improvement, ~250 fps avg, ~140 low, ~333 high (on an m4). Looks pretty straightforward to do threading with as well. Cool stuff! Could work to bring more gpu stuff back down to the cpu.
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refulgentis
4 hours ago
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Tl;dr: SDFs are really slow but cool because they can compactly define complex stuff; demoscene uses it. Sort of the functional programming to trad renderings OOP. Would be cool if it was faster. Optimizing an algorithm for CPU rendering using recursive divide and conquer, 1 core with one object gets 50 fps. 100 fps if you lerp a 10x10 pixel patch instead of doing 1 pixel. Algorithm isn’t optimized, fully. Also, turns out the author’s idea is previously known but somewhat obscure, it is referred to as “cone marching”
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01HNNWZ0MV43FF
4 hours ago
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Holy crap! The demo is hitting 30 FPS from certain angles, on my decade-old CPU
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01HNNWZ0MV43FF
1 hour ago
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Readers might also enjoy this: https://www.youtube.com/watch?v=il-TXbn5iMA

"I'm making a game engine based on dynamic signed distance fields (SDFs)"

That project is for GPU and it works by caching SDFs as marching cubes, with high resolution near the camera and low resolution far away, to build huge worlds out of arbitrary numbers of SDF edits.

So it probably wouldn't stack with these CPU optimizations that directly render the SDF at all.

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