Olivier Therrien

@SoftEngineer Also @Mirko_Salm released an improved algorithm that is more physically accurate: shadertoy.com/view/lfdBWn

SSGI (screen-space global illumination) in WebGPU. Technically this is "near-field diffuse screen-space ray-traced indirect lighting". We trace SSAO, and as we sweep arcs - we also integrate lighting along the occluded arc. This is a very natural extension to GTAO or any other horizon-based technique, as it already sweeps arcs. The irradiance is encoded in a u32 texture using rgb999e5, so it's quite compact. I'm not doing any denoising here, in practice you would apply at least spatial denoising. Writeup: discourse.threejs.org/t/ssgi-screen-…

@SoftEngineer We published a paper to fix exactly the problems that you mention at the end of the writeup: arxiv.org/pdf/2301.11376 Here are a few implementations: github.com/cdrinmatane/SS… shadertoy.com/view/dsGBzW

Meanwhile Suslik (Alexander Sannikov) is improving Radiance Cascades for the general 3D case: youtube.com/watch?v=rG2aok…

Capsaicin is not just for tacos, it's also our developer rendering framework! v1.3 is out now: 🌶️ Added heat with GI-1.2, which includes multiple-bounce indirect lighting. 🌶️ HDR support with spicier tone mapping. And much, much more: gpuopen.com/learn/gi-1-2-m…

A bit technical thread 🧵 I’ve been improving the in-game ambient occlusion system - and ended up with something I call: Blob-based Analytical Ambient Occlusion on Primitives Here’s what it does to the final image: (more examples later in the thread) (1/16)

SSGINode: New node for screen-space global illumination github.com/mrdoob/three.j…

Distant light sampling for GT-VBAO with different quality options: shadertoy.com/view/wc2SzR (+ the math: shadertoy.com/view/wcsXDN)

Nice li'l new video covering (some of) the history of SSAO algorithms: youtube.com/watch?v=g4or1f…

@AlanPereiraArt @bjornornorn @Mirko_Salm There is also a blog post and slides: cdrinmatane.github.io/posts/ssaovb-c…

@bjornornorn @Mirko_Salm @volfaze Hey, that seems great! Where can I find the VBAO paper? Also, what API are you working with? Vulkan?

I'm working on a AO and GI for my game. For that reason I'm extending @Mirko_Salm's GT-VBAO (based on @volfaze's work). I've done two things so far: - Sampling a distant light instead of computing AO - Added a heuristic for estimating occluder thickness Details and links below

@AlanPereiraArt @bjornornorn @Mirko_Salm Paper is here: arxiv.org/abs/2301.11376

@Mirko_Salm Nice! For the cosine weighted version, if you do a dot product with the tangent (of projected normal) instead of view, I think samples would already be in cosine space and won't require acos

Optimized version of uniformly weighted GT-VBAO: shadertoy.com/view/4cdfzf. No more acos calls.

@NickChapmn @Mirko_Salm has worked on a more physically correct version of the algorithm, maybe he has some thoughts on this.

@NickChapmn (3/3) Maybe a more accurate way to do this would be to reweight the final contribution so it adds up to 1 (untested). Just removing the term and assuming the sample covers the entire sector is certainly more correct.

Hi, @volfaze , regarding the 'Screen Space Indirect Lighting with Visibility Bitmask' paper - first off great work, it's such a clever idea. It's fantastic to get realtime indirect illumination, even if it is in screen space :)

GT-VBGI: Ground Truth Visibility Bitmask Global Illumination: shadertoy.com/view/lfdBWn. image: GT-VBGI (left) vs. Reference (right). 2. image: the same as the 1., but converged. GT-VBGI matches the results of a brute force ray-marcher.

Got screen-space global illumination working! (still pretty hacked up)

@Mirko_Salm Nice! Is there more noise with the unidirectional GT-VBAO?

unidirectional GT-VBAO: shadertoy.com/view/Xc3yzs 1. image: GT-VBAO (left) vs. Reference (right); single direction. 2. image: the same as the 1., but converged. No need having to always ray march bidirectionally anymore.

GT-VBAO: Ground Truth Visibility Bitmask Ambient Occlusion: shadertoy.com/view/XXGSDd 1. image: GT-VBAO (left) vs. Reference (right). 2. image: the same as the 1., but converged. GT-VBAO matches the results of a brute force ray-marcher. This work was partially funded by @1000orks.

The quest for the best SSAO continues!💪 SSRT3 raw.githack.com/zalo/three.js/… GTVBAO raw.githack.com/zalo/three.js/… #issuecomment-2448548561" target="_blank" rel="nofollow noopener">github.com/mrdoob/three.j…