Excited to share our latest work on discrete SDF reconstruction with no gradients required! Please come to Xiana's talk in LA :)

Ever since I have worked in mesh reconstruction from SDFs, the general consensus was "to get sharp features, you need access to the SDF gradient (e.g., with dual contouring)". Amazingly, Xiana shows that this is not true, and one can reconstruct sharp features from SDF data alone. Crazy!

6/6 Huge thanks to my wonderful coauthors @ninnnnnglala.bsky.social, @topher-batty.mastodon.acm.org.ap.brid.gy , @odedstein.bsky.social, and my amazing PhD advisor @silviasellan.bsky.social. Check our paper here: gatc.cs.columbia.edu/assets/pdf/d... (Code release coming soon!)

5/6 The results are sharper and more accurate reconstructions from sampled SDF data, especially at medium-to-high grid resolutions, with applications to narrow-band meshing and swept-volume reconstruction.

4/6 We then incorporate these constraints into local, parallelizable quadratic optimization problems to refine mesh vertex positions, and iteratively update the intersections between edges and the isosurface, as well as their corresponding gradients, to recover sharper geometry.

3/6 Our approach revisits the classic Dual Contouring, but removes the need for exact gradients as input. To do so, we leverage the fact that each SDF sample gives distance information in the form of a spherical constraint that the unknown surface should be tangent to.

2/6 SDFs are widely used in modeling, simulation, manufacturing, and graphics, but many downstream tasks still need explicit surface meshes. From grid samples alone, sharp reconstruction is hard, and existing methods often smooth features or require extra information.

1/6 Excited to share our #SIGGRAPH2026 paper, Dual Contouring of Signed Distance Data! We propose a new method for reconstructing sharp meshes from discrete samples of signed distance functions (SDFs) that does not require gradients. Project page: gatc.cs.columbia.edu/projects/dua...

This is a really cool paper!

What an impressive cohort!!!

We are excited to announce the 2026 cohort of Rising Stars in Computer Graphics 🌟 These 9 young researchers will participate in a workshop at Siggraph 2026, about the wide range of career trajectories in graphics. Thank you to all applicants and to our selection committee for all the hard work.

Proud of my students for their research, which for the first time located the descendants of those enslaved by Columbia University's founders. www.columbiaspectator.com/news/2026/05...

May 3, 1968 the #GratefulDead got smuggled past student barricades into the quad at Columbia University in NYC to play a stealth concert for the students who were protesting youtu.be/WFtQr_W3opM?... 📷 Rosie McGee

I am continually asked if VFMs "understand" classical mechanics and my benchmark for this is the venerable newton's cradle. Let's take a look at progress over the last year using Google's Veo models -- a 🧵

I never understand what I'm supposed to write here

At #CHI2026 we are also presenting "StepDance: A Toolkit for Redesigning CNC Machines Using Physical Metaphors" Curious how a machine-building novice like me can make a sketch-to-print machine? checkout the talk on Friday >> programs.sigchi.org/chi/2026/pro... or see thread...

This is not what "opt in" means...

Short and to the pointless,

Technical Reading, Week 7: "Comment on Computer Rendering of Fractal Stochastic Models", Mandelbrot's angry letter to future Pixar folks about the crapola Genesis Sequence in Star Trek 2: Wrath of Khan. (His views, not mine.) dl.acm.org/doi/10.1145/...

If someone refers an undergraduate student to a known sex offender for a job, and includes a comment about how good-looking the student is in their recommendation letter, that someone should never be allowed to teach undergraduate students ever again.

The CVPR review period is *Dec 18 to Jan 12*? Damn....

The ACM Digital Library, where a LOT of computing-related research is published (I'd say at least 75% of my own publications), is now not only providing (without consent of the authors and without opt-in by readers) AI-generated summaries of papers, but they appear as the *default* over abstracts.

This is really, really bad!

Writing code on a bumpy train and tried stabilizing the display image to my head -- it does (surprisingly) make things a bit easier to read but overall feels too weird to actually use.

The Graphics Replicability Stamp Initiative (GRSI, www.replicabilitystamp.org), a community-driven initiative to promote replicability in Graphics research, is seeking volunteers. More details in the 'Volunteering' section of the home page.

“it’s October 3rd” Happy K-Mean Girls Day to those who celebrate

cvoelcker.de/blog/2025/re... I finally gave in and made a nice blog post about my most recent paper. This was a surprising amount of work, so please be nice and go read it!

Best illusion I've seen in a while

This is the metareview

How can one reconstruct the complete 3D interior of a wood block using only photos of its surfaces? 🪵 At SIGGRAPH'25 (Thursday!), Maria Larsson will present *Mokume*: a dataset of 190 diverse wood samples and a pipeline that solves this inverse texturing challenge. 🧵👇

These appear to be constructed "wormholes", to go by www.reddit.com/r/googlemaps... . There's a technique to create them, but one person wrote, "I didn’t want the technique to be publicly known and easily accessible, as it is (though minor) a kind of google streetview vandalism."

The Internet Roadtrip is now trying to cross Labrador. A 100-foot gap in Street View coverage almost forced them to turn back, but as they approached the break, someone got a friend in Labrador City to drive to the spot IRL and take and upload a panoramic photo to fix it. neal.fun/internet-roa...

"Giving pedestrians a 7-second head start at traffic lights is associated with a 33% reduction in total pedestrian injuries—both fatal and non-fatal—at New York City intersections."

Asking the OpenAI Whisper audio model to transcribe 30 seconds of silence generates the output "ترجمة نانسي قنقر", which is "translation by Nancy Qanqar". Nancy Qanqar is a volunteer translator of (among other things) many pirated movies, so that invites an interesting conclusion on data sources.

Replication Crisis xkcd.com/3117/

Got an MRI so I played with some renders of the inside of my melon. #metalrt #rendering

At ICML, we're presenting a paper on uncertainty-aware surface reconstruction! Compared to previous approaches, we are able to completely remove the need for recursive linear solves for reconstruction and interpolation, using geometric GP machinery. Check it out!

🚨🚨 WiGRAPH CONFERENCE COFFEE @ SIGGRAPH '25 🚨🚨 Sign up now to be randomly matched with peers for a SIGGRAPH conference coffee!

The materials of my graduate school course at #SGP2025 on "Deep Learning on Meshes and Point Clouds" are live on rubenwiersma.nl/deeplearning. A 'map' for 3D deep learning, covering the basics and thoughts on when and where to use deep learning tools in 3D.

It is with great pleasure that I share MAXMINDS 2.0, a new Max Planck program to support scholars in danger of displacement by war or natural disasters, and who have limited access to resources and institutional support. If you know affected scholars, please share. www.maxminds.mpg.de

I signed and encourage colleagues to do the same. Venue selection is fraught. Inevitably attendees will encounter visa issues, distance, expense, local politics, and other challenges. This venue, however, is simply unsafe for LGBTQ+ researchers, and the leadership's defensiveness is unacceptable.

Holding SIGGRAPH Asia 2026 in Malaysia is a slap in the face to the rights of LGBTQ+ people. Especially now, when underrepresented people need as much support as we can possibly give them ! Angry like me ? Sign this open letter to let them know. 🏳️‍⚧️🏳️‍🌈 docs.google.com/document/d/1...

Our work “Geometry in Style” will be presented at #CVPR2025 on Sunday at 4pm in ExHall D, poster 219. Drop by and say hi! Our technique is capable of performing expressive text-driven deformations that preserve the input shape identity. 1/

This is good. I’ve been willing to ignore “AI gives people religious mania” just because it sounds like the classic satanic panic sparked by every trend from the Beatles to D&D. But Andy runs the numbers and confirms.

MIT News today features a paper with fun examples coming out this summer by our brilliant PhD student Leticia Mattos Da Silva, postdoc—and Columbia professor in a matter of days!— @silviasellan.bsky.social, and PhD student collaborator Natalia Pacheco-Tallaj. news.mit.edu/2025/animati... Flubber!

We’re in the MIT news! Read about Leticia’s amazing new SIGGRAPH paper and the most fun I’ve had during my time at MIT! news.mit.edu/2025/animati...

Selena's #Siggraph25 work found a simple, nearly one-line change that greatly eases neural field optimization for a wide variety of existing representations. “Stochastic Preconditioning for Neural Field Optimization” by Selena Ling, Merlin Nimier-David, Alec Jacobson, & me.