This article is a great dive into the nuts and bolts of creating one of those tiny (but neat) shaders. Both in terms of algorithms and GLSL character minimization! blog.pkh.me/p/45-code-go...

A new video of a wobbly cube that's rendered via ray-marching a discretized SDF. Hypnotic! Distances are reconstructed via trilinear interpolation of cached values on a grid. This is the equivalent of what was shown in my earlier 2D animations (see below!)

New take on the tunnel gun: Make a tunnel, walk through it, and then close it up behind you. Going to experiment with this for gameplay in a mining context.

Demo of bilinear interpolation of SDF samples: - Negative (interior) samples of the analytic SDF are blue, positive (exterior) samples are orange. - Circles are drawn around samples to show distance magnitude. - Intermediate bilinear interp samples / segments are drawn. 1/

Making an animation illustrating sparse allocation of SDF bricks: - White line is the analytic SDF curve. - Sparsely-allocated cells (and distance samples) are shaded. - Yellow line in the reconstructed SDF curve from cached samples (via bilinear interpolation of distances).

Just learned that the equivalent of "warp"/"wave" in ispc is a "gang". "Gangs of Program Instances" has a certain menacing ring to it 😁

My foes when I confront them

A lesson I've learned: digging holes into shiny red stuff always ends up looking pretty gross🤨

I want to save/load scene data in my engine, but I don't want to implement a real system for this yet (partly laziness, partly don't want to commit to a design). So my quick solution is to dump literal C++ code that creates all scene objects. Then copy/paste into my init code😂

From my notes about stuff to add in the video about my engine (lol)

Playing around with a "tunnel gun" that can open a tunnel in front of you that can be looked into or moved through. This type of thing is really simple in my engine - just spawn an SDF capsule subtraction that is locked to the player's view.

Playing around more with the Donut County vibes - but this time you have both a portable hole and a portable mound. And the hole grows bigger when it consumes cubes, because that's what holes do (obviously).

Feeding the hole.

Herding cubes, HD remaster.

Finished work on directional light shadows (for now!). This took a while because I didn't implement "normal" cascaded shadow maps (via frustum slices) but rather world-space cascades that are updated in chunks as the camera moves, and incrementally when the scene changes. 1/

I found that in addition to NVRHI (which I discussed previously on here) NVIDIA, somewhat confusingly, also provides NRI ("NVIDIA Render Interface"). NRI is intended to be a low-level interface wrapping D3D12 and Vulkan, whereas NVRHI also wraps these APIs but simplifies some ..

Teardown was released 5 years ago, has sold millions of copies, and was acquired (super rare for an indie game) - and yet it still has effectively no clones/competitors. Shows how powerful having insane technical skills can be.

As a kludge for lack of global illumination (which I plan to add eventually), I am attenuating the visibility of ambient lighting (the skybox) deeper within the terrain. One of the benefits of using SDFs - just eval the terrain SDF to get distance to surface for any point!

Experimenting with a SDF material blend function that is "stamps" the material volumetrically. The previous function I was using (which is the common one) blends the material around the surface influence area, and so would have no effect below ground.

Almost finished implementing shadows. This ended up being a bigger project than expected, as I decided to render world-space shadow map cascades that update/"scroll" incrementally as the camera moves. The benefit of this is that very little work needs to be done every frame!

You mock, but this is actually art.

Prowling around the SDF yards after dark, desecrating spheres with reckless abandon.

Playing with RenderDoc's shader debugger, and the "Run forwards to NaN/Inf" feature is incredibly useful and got me to the problem in one click. [a story continued... ⬇️ :) ]

Nicely-explained and illustrated article on making a spherical Minecraft-style blocky world. (with playable web demo) www.bowerbyte.com/posts/blocky...

TIL the concept of a "net" of a polyhedron - the way its faces can be flattened and then "folded" back together. These are 11 nets of a cube! en.wikipedia.org/wiki/Net_(po...

While searching around for solutions to geometric problems, I periodically end up on this big list of PDFs written by Dave Eberly that cover a lot of topics rigorously. Recommended! www.geometrictools.com/Documentatio...

Great article by @aras-p.bsky.social comparing the perf of rasterizing single-pixel triangles vs. compute-shader splatting. The most fascinating part of this is how much different GPUs differ in comparative perf, and how they respond to different scenarios. aras-p.info/blog/2025/08...

I've noticed a huge difference in my ability to tune parameters and have an intuition about the tuning space when I add a control (e.g., slider) to drag continuously through the space. Being able to type in values is great too (either UI or hot-reloaded code), ...

A trick I forget about with shading languages is that you can left-multiply vectors with matrices to transform by the transpose. So if you have a rotation matrix "worldToLight", you can use both: worldToLight * worldPos -> lightPos lightPos * worldToLight -> worldPos 1/

Digging with spheres (🔵) vs octahedrons (🔷)

Read this recent paper on hierarchical pruning/culling of SDF operations, and it presents a really appealing approach that's simple to implement and pretty general. wbrbr.org/publications... However! I see that they don't address incremental updates to the structure ...

Just make it exist first. You can make it worse with each new pass while getting increasingly frustrated later.

This is what I came up with to calculate a tight AABB for an octahedron. The 6 vertices of the octahedron all lie on a single axis, so they each "pick" a single column of the rotation matrix. abs() handles the fact that the vertices are mirrored w.r.t. the origin. Demo below!

Added octahedrons to experiment with them as a digging primitive and ran into an issue when getting "corner radius" working. This is the fixed version - very satisfying :) (explanation below) 1/

Experimenting with "digging" using rotated cubes as the subtraction primitive instead of spheres. I like the jagged/angular/detailed look, but I'm going to try other shapes (like tetrahedron or pyramid) that aren't all right angles.

Added "corner radius" / rounding, which is easy to apply to any SDF shape that has an exact (outer) distance function - just subtract the radius from the scale and then offset the computed distance by the same radius. So you get rounded shapes "for free" with 1 subtraction. 1/

Made it seamless to switch between "edit" and "play" modes in my engine - toggle between them instantly with a shortcut. Super low-friction, and feels good! Granted right now "play mode" lets you walk around and that's about it :D

Another very cool alpha-to-coverage WebGPU demonstration. This one actually will test the A2C sample thresholds / dithering on your GPU and generate shader code to emulate it! (scroll to the bottom of the right pane) kai.graphics/alpha-to-cov...

Got a character controller working using Jolt's kinematic controller with simple WASD movement and a "jetpack." Works pretty well out of the box! Makes the world feel a lot more concrete.

Highly recommend both of these "Teardown frame teardown" articles. The Teardown renderer is pretty unique and there is a lot of food for thought in how it does things. acko.net/blog/teardow... juandiegomontoya.github.io/teardown_bre...

I enjoy reading old real-time rendering presentations where they talk about wanting rendering API / GPU features that weren't out yet.

This article (and associated sample app) by Matt Pettineo is getting old, but it's such a valuable resource on (cascaded) shadow mapping techniques. So valuable to compare techniques and tweak settings in the sample app. therealmjp.github.io/posts/shadow... github.com/TheRealMJP/S...

More ChatGPT hallucination hilarity - it links to a gdcvault.com talk, using the numerical id of an actual talk but changing the talk name in the URL (that's cosmetic only) to a different name than the actual talk. (And says it has a different speaker as well.) Sigh.

I am intrigued by the approach to directional shadow maps described in this presentation - in particular, cascades are cached world-space regions centered around the camera (not view-dependent). Are there other resources on this type of technique? www.youtube.com/watch?v=0QYE...

If you want to go even deeper down the depth buffer precision rabbit hole, this article is great: zero-radiance.github.io/post/z-buffer/

I like taking the laziest / most-minimal-possible approach to development. E.g., right now I test rendering changes by taking before/after screenshots, dragging them into Chrome and flipping back and forth with keyboard shortcuts. Would this work on a huge team with a 10-million

Better demonstration of the new (screen-space) ambient occlusion effect. Always satisfying to see lighting update with dynamic geometry modifications.

Nice li'l new video covering (some of) the history of SSAO algorithms: youtube.com/watch?v=g4or...

I spent way too long getting this ambient occlusion effect working. Subtle, but grounds objects, especially when they're moving. I ended up using GTAO, using an implementation based on Intel's XeGTAO: github.com/GameTechDev/... Still need shadows :)

It's cool that Chrome's new renderer/rasterizer (Graphite) is using Dawn (Chrome's WebGPU implementation) as its GPU abstraction layer. "Dogfooding" it like this means they're going to be extra-serious about perf/features/etc. blog.chromium.org/2025/07/intr...