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A Recursive Algorithm to Render Signed Distance Fields

40 pointsby surprisetalklast Wednesday at 2:10 PM3 commentsview on HN

Comments

linolevanyesterday at 9:45 PM

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.

refulgentisyesterday at 8:58 PM

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”

01HNNWZ0MV43FFyesterday at 9:04 PM

Holy crap! The demo is hitting 30 FPS from certain angles, on my decade-old CPU