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SniperJake945 @tearsofjake.bsky.social · Aug 13

I appreciate the kind words!!! I really enjoyed hanging out with you and the jangafx team!!! Y'all are absolutely wizards 🧙‍♂️🧙‍♂️🧙‍♂️🧙‍♂️

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Yining Karl Li @yiningkarlli.bsky.social · Aug 10

At 10am this morning at SIGGRAPH, my teammate Nathan Zeichner will be presenting our talk about a texture streaming system for Ptex on the GPU that we built for our in-house interactive pre-viz GPU path tracer; the talk is by Nathan, Mark Lee, and me.

s2025.conference-schedule.org/presentation...

Presentation - SIGGRAPH 2025 Conference Schedule

s2025.conference-schedule.org

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SniperJake945 @tearsofjake.bsky.social · Jul 29

The github repo also includes links to some shader toy demos, so check those out! Here's one for noise on an SDF surface :)

shadertoy.com/view/WXdXzj

Shadertoy

shadertoy.com

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SniperJake945 @tearsofjake.bsky.social · Jul 29

The least obvious part of all of this is how to construct that metric tensor G from a given vector, but it turns out it's super straight forward. The attached example shows how to do so for a 3D metric tensor. In our paper we outline specific bounds for the sizing of this metric.

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SniperJake945 @tearsofjake.bsky.social · Jul 29

Just to elucidate the idea a bit more, on the left we have the original perlin noise algorithm, and on the right we have the steerable version, with the changes underlined in red. We simply add a second set of weights, and incorporate our metric into the original dot product step

showing the difference between algorithms.

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SniperJake945 @tearsofjake.bsky.social · Jul 29

New at #SIGGRAPH2025:

Can we make Perlin Noise stretch along some underlying vector field? Well it turns out it's possible with two simple additions to the original method! No need for advection or convolutions.

Find the paper and implementations here:
github.com/jakericedesi...

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SniperJake945 @tearsofjake.bsky.social · Jul 29

Hehehehehehe thanks for posting this Karl and for all the support on the paper!!! ❤️

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Yining Karl Li @yiningkarlli.bsky.social · Jul 28

One of my coworkers, @tearsofjake.bsky.social, has a talk at SIGGRAPH this year about this really cool steerable perlin noise technique that was used on Moana 2. He's just posted some handy reference implementations for Houdini, Unity, Godot, and Blender; check it out!

github.com/jakericedesi...

GitHub - jakericedesigns/SteerablePerlinNoise: Implementations of "Steerable Perlin Noise" as presented at Siggraph 2025

Implementations of "Steerable Perlin Noise" as presented at Siggraph 2025 - jakericedesigns/SteerablePerlinNoise

github.com

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Daniel Holden @theorangeduck.bsky.social · Apr 4

Time for another long blog post... and today it's all about how we handle the temporal aspect of animation data. And more specifically, how to approach things from a signal processing perspective, covering up-sampling, down-sampling, and everything in-between.

theorangeduck.com/page/filteri...

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SniperJake945 @tearsofjake.bsky.social · Jun 16

In anisotropic meshing the metric is defined at all points in space and you use something like fast marching (basically a fancy dijkstras) to generate anisotropic distances. The hacky version would be to give each voronoi pt a metric and swap the euclidean distance calc for the metric equivalent.

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SniperJake945 @tearsofjake.bsky.social · Jun 16

For anisotropic voronoi M will be some metric tensor or in easier terms just a positive definite matrix (non zero positive eigenvalues).

One way of generating that matrix is by following the steps outlined in this paper (eq. 9): bougleux.users.greyc.fr/articles/bou...

bougleux.users.greyc.fr

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SniperJake945 @tearsofjake.bsky.social · Jun 10

Yeah, I'm finding that as the resolution of the 3d grid increases the precision issues really start to compound specifically for the SAT computation. I'll stick with 64bit precision in that case! Either way the results are so cool, really amazing work!!!!

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SniperJake945 @tearsofjake.bsky.social · Jun 10

If I naively clamp the magnitude of velocity to be at most 1, with 100 timesteps it seems to converge, however if I drop the time steps to something like 10, it no longer converges. So I guess I was curious if there was some way to intuit what a good upper bound for vel magnitudes would be?

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SniperJake945 @tearsofjake.bsky.social · Jun 10

Such a cool paper! I tried implementing this with 32 bit precision and it seems much more noisy in the output (which makes sense). I was curious if you had any thoughts with respect to clamping/limiting velocity values? Almost like a cfl condition of sorts...

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SniperJake945 @tearsofjake.bsky.social · Jun 8

I do love that true solutions never have crossing edges leaving you with a nice simple polygon.

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SniperJake945 @tearsofjake.bsky.social · Jun 8

Assuming I understand the question correctly:
www.geometry.caltech.edu/BlueNoise/

And then there's a linear time algorithm for it using a paper from this year's siggraph:
perso.liris.cnrs.fr/david.coeurj...

Blue Noise through Optimal Transport

www.geometry.caltech.edu

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Nicolas Bonneel @nbonneel.bsky.social · May 5

A thread on our new, also awesome, Siggraph paper "Linear-Time Transport with Rectified Flows", by K. Do, @dcoeurjo.bsky.social, P. Memari and me.
Paper here: perso.liris.cnrs.fr/nicolas.bonn...
Results in video: youtu.be/EcfKnSe6mhk

Linear-Time Transport with Rectified Flows

YouTube video by David Coeurjolly

youtu.be

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SniperJake945 @tearsofjake.bsky.social · Mar 16

How do I get the discover page to align more with my interests? I've tried following a bunch of people, but it still kinda just shows stuff based off whatever categories I clicked when I signed up...

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Matt Ebb @mattebb.com · Feb 6

I know it’s a bit uncool to linkedin-post on here but we’re hiring at work, I’ve been looking at quite a lot of showreels, so I wrote up some tips for making a great fx reel #vfx
www.linkedin.com/pulse/creati...

Creating a stand-out Effects reel

As a VFX artist, your showreel is one of the most important tools in the job search process. Whether you’re trying to break into the industry or looking for a new role, having a stand-out showreel can...

www.linkedin.com

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SniperJake945 @tearsofjake.bsky.social · Jan 4

Distances to LP Voronoi Edges :)

shadertoy.com/view/MXVyz1

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SniperJake945 @tearsofjake.bsky.social · Jan 3

The painting app rebelle is super fun to play with. I know Craig Mullins (the GOAT) has some a cool time lapse on Instagram where he used it.
www.instagram.com/reel/CzXYoAA...

Login • Instagram

Welcome back to Instagram. Sign in to check out what your friends, family & interests have been capturing & sharing around the world.

www.instagram.com

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Reposted by SniperJake945

Morten Vassvik @vassvik.bsky.social · Dec 9

So what is the tiniest possible fluid simulation?

Can we get anything interesting from a single cell?

For this we'll be using a standard MAC grid, which means we'll represent horizontal velocities (red) on the vertical edges and vertical velocities (green) on the horizontal edges of each cell.

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SniperJake945 @tearsofjake.bsky.social · Dec 18

If you were curious why I was after the intersections of paraboloids, this is why! :)

bsky.app/profile/tear...

SniperJake945 @tearsofjake.bsky.social · Nov 26

Is there a robust and fast way of finding the nearest point on a paraboloid of form: (x,y, f(x) + f(y))
where f() could be any range of convex functions, like x^2 or x^4?

So like given a point (p0,p1,p2) minimize:
(x - p0)^2 + (y-p1)^2 + ((f(x) + f(y)) - p2)^2
With respect to x and y.

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SniperJake945 @tearsofjake.bsky.social · Dec 18

It's unfortunately not exact, due to using an iterative method to solve the problem (Alternating Projections). But it extends to higher dimensions, and works for any norm >= 2

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SniperJake945 @tearsofjake.bsky.social · Dec 18

Distances to the boundary of voronoi in L4.

shadertoy.com/view/lfKfWV

Hopefully it doesn't crash webgl on your device! :)

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