iiinova — where your digital self keeps evolving

Pekka Väänänen @pekkavaa.bsky.social · 3h

I'm still working on the Palette Programming book. I planned an Early Access release for October with roughly half the chapters. But the last few writing sessions I've just spent studying the differences between the impressionist and the divisionist techniques and Frank J. Reilly's palette premixing

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Pekka Väänänen @pekkavaa.bsky.social · 09/10/2026

Color science in the wild: "Beer color is measured in Degrees Lovibond, a metric based on the Munsell system" en.wikipedia.org/wiki/Beer_me...

en.wikipedia.org

Beer measurement - Wikipedia

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Pekka Väänänen @pekkavaa.bsky.social · 17/09/2026

The E3 demo in question: www.youtube.com/watch?v=8ZJ4... Naturally, the in-game shots begin with a shiny parallax mapping and Havok physics show :) Followed by Patrick Stewart hype second. Interesting how they had soft shadows in the demo but cut them from the game before release.

youtube.com

The Elder Scrolls IV: Oblivion - E3 2005 Demo

Official demo of The Elder Scrolls IV: Oblivion by Todd Howard, first shown at E3 2005, published 18 May 2005. The Elder Scrolls IV: Oblivion release dates: - Windows PC: 20 March 2006 - Xbox 360:…

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Pekka Väänänen @pekkavaa.bsky.social · 17/09/2026

I enjoyed this 41 minute documentary filmed before the E3 2005 reveal of Elder Scrolls IV: Oblivion www.youtube.com/watch?v=zvm0... Found it funny how they staged a scene of artists traveling to Washington D.C. to capture textures for the game's Imperial City.

youtube.com

The Making of Oblivion (FULL | HQ | ENG)

Making of GOTY 2006

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Pekka Väänänen @pekkavaa.bsky.social · 14/09/2026

I decided to discuss this in my book so I made this plot today. Still need to edit the caption for clarity. Surprisingly, 2-LSB triangular noise didn't hide banding in an error plot. I don't understand why. Some "waves" also seen here. Also unclear why exactly does changing to uniform work at all...

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Max (VGCartography) @vgcartography.com · 11/09/2026

nintendo 64 desertification 🏖️

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Don Williamson @donw.bsky.social · 09/09/2026

In ~2007 when coding the ambient lighting of Splinter Cell, I had the idea of storing dynamic SH probes in Voronoi cells, where a) dynamic objects could walk/lerp the face graph, and b) static meshes "palettised" probes per vertex and lerped to give Realtime GI. It never shipped but look how pretty!

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Jason Scott @textfiles.com · 08/09/2026

Of all the formats for newsletters, zines and information indexes, I'd honestly have not thought people would use WinHelp format. But Vannevar K has collected hundreds of examples of WinHelp formated documents, all conveniently emulated in Windows 3.1.

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Pekka Väänänen @pekkavaa.bsky.social · 07/09/2026

I didn't know it was unfinished. Really interesting. Also, apparently I missed the crypt on my visit! :(

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Pekka Väänänen @pekkavaa.bsky.social · 07/09/2026

It's an incredible building. Almost felt "overdesigned" as if the architects wanted to one-up every other basilica ever!

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Pekka Väänänen @pekkavaa.bsky.social · 07/09/2026

And a final clarification: the example comparison I attached is error diffusion indeed and not ordered dithering. There grayscale amplitude*(1,1,1) noise is added to the error-compensated color before looking up the closest color in the palette. So it's dithering type A applied to dithering type B😃

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Pekka Väänänen @pekkavaa.bsky.social · 07/09/2026

To be clear, I'm talking about ordered dithering. In error diffusion, it's clear that you need linear RGB for the output to visually mix to the original color (when seen from a distance). So my reasoning is that the same should apply to ordered RGB dithering too.

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Pekka Väänänen @pekkavaa.bsky.social · 07/09/2026

In my case, the noise amplitude has to be larger. It's a 16-color image and the individual output levels are spread wider. So it's not too far from Lottes' HDR->SDR dithering situation. I *think* linear space noise makes more sense then and it needs a constant amplitude to average to 0.

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Pekka Väänänen @pekkavaa.bsky.social · 07/09/2026

Thank you. This was a great summary (I've studied the INSIDE slide deck earlier). So in this case, you add 2LSB TPDF noise to the gamma-space values before integer quantization (done by the GPU as trunc(x+0.5)) but switch to 1LSB [-0.5, 0.5] rectangular noise for c<0.5/255 and c>254.5.

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Pekka Väänänen @pekkavaa.bsky.social · 04/09/2026

I've been racking my brain over linear space dithering. Adding noise sounds simple but how much, exactly? Finally, I found a trick: scale the dither down near zero. Found from Timothy Lottes 2016 slide deck. Attached is an exaggarated example.

A two-pane comparison of Floyd-Steinberg dithering with threshold noise. Left: linear space noise is added with constant magnitude. Right: linear space noise but magnitude is scaled down near zero.

A slide from "Advanced Techniques
and Optimization of
VDR Color Pipelines" by
Timothy Lottes (2016)

https://gpuopen.com/download/GdcVdrLottes.pdf

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Collin Allen @command-tab.com · 03/09/2026

The #N64 development scene has been making huge strides recently. I blogged about where things stand right now: Also, that chunky header image took a *while* to make 🥹

command-tab.com

The Nintendo 64 Renaissance

The N64 homebrew scene now has better developer tools and support than ever

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Reposted by Pekka Väänänen

Nelarius @nelarius.bsky.social · 31/08/2026

While investigating #voxel rendering alternatives that don't involve generating triangles, I ran into the "Voxel GI with Nested Axis-Aligned Distance Fields" paper. github.com/cg-tuwien/NA... Super promising method, with adapted code, I can render RTAO with 1 billion voxels on an M2 Macbook Air!

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Pekka Väänänen @pekkavaa.bsky.social · 01/09/2026

I went and checked and actually I used a trick by Timothy Lottes: launch all levels of Z pyramid in a single pass but the lower levels start at t=0 if their parent didn't finish yet. Gave a 20% boost. My messy writeup if you happen to be interested: peisik.untergrund.net/rendering_et...

peisik.untergrund.net

Rendering Eternal Fortress

We store 20 million points in a big fat ring buffer, and on each frame we add about two million (1920 × 1080, one ray per pixel) new ones to it, dropping out the oldest points.

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Pekka Väänänen @pekkavaa.bsky.social · 01/09/2026

Super neat. I've done this as a separate "Z prepass" and I recall it was difficult to choose the cone size and the later ray start position to be conservative but not too large.

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Nexxtic (Selaco Lead Dev) @selaco.bsky.social · 27/08/2026

Being able to bake shadows into the Doom Engine is so freaking cool.

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Pekka Väänänen @pekkavaa.bsky.social · 25/08/2026

Hexagonal-grid dithering looks pretty wild up close, especially the 50% case here. A crop of a figure from "Alpha stable modeling of human visual systems for digital halftoning in rectangular and hexagonal grids" by González et al. 2008.

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Pekka Väänänen @pekkavaa.bsky.social · 17/08/2026

Updated the article with a discussion on this 2023 blog post by Chris Lomont: lomont.org/posts/2023/a... Link to the new section: 30fps.net/pages/255-vs...

A reconstruction error plot with "Input value" on the X-axis and "Reconstruction error" on the Y-axis. Three thick bands where the blue "Standard" and orange "Alternative" lines are very similar. A green "Third" band goes over the plot diagonally, showing high negative error near 0.0 and high positive error near 1.0.

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Pekka Väänänen @pekkavaa.bsky.social · 05/08/2026

Exactly right. Even a poor VGA cable would probably add just horizontal blur. Here I took photos on an LCD screen with HDMI and VGA and a weak argument could be made that perhaps some art was authored with the "horizontal blur" in mind. I have no idea if that actually happened.

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Robin Green @fatlimey.bsky.social · 03/08/2026

Ever wondered what a test card is for? TV signals are encoded in the YUV or YCbCr color spaces. A vectorscope is just the CbCr or UV part of the signal in 2D. Running a SMTPE test card through the scope gives you a zigzag pattern where it visits the center of each primary box in a specific order.

The SMTPE test card, electronically generated.

An oscilloscope image with lines and boxes printed on the screen. The green lines of the oscilloscope are tracing out a pair of interlocking zigzags that exactly hit the centers of the boxes. Science!

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Pekka Väänänen @pekkavaa.bsky.social · 04/08/2026

What do you call the act of inserting an element to a sorted list? "Insort" of course... A snippet of a guide in the Python language docs.

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Pekka Väänänen @pekkavaa.bsky.social · 04/08/2026

An interesting insider view from the SGI side to Nintendo 64's development and launch: steveshepard.com/blog/making-...

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Pekka Väänänen @pekkavaa.bsky.social · 20/07/2026

Very convincing. They look great.

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Pekka Väänänen @pekkavaa.bsky.social · 20/07/2026

Hey that's a cool idea. Not sure how exactly it would work but at least some sort of "good neighbors for dithering" matrix could be built. I also got decent results by emphasizing luminance and hue differences more in color selection (at the expense of saturation error) without any explicit ramps.

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Pekka Väänänen @pekkavaa.bsky.social · 20/07/2026

Cool! How do you use the dither matrix in color selection, if I may ask? Do you apply it as additive noise and then perform per-pixel closest color search (I called the "offset" approach in my text), or something different?

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Pekka Väänänen @pekkavaa.bsky.social · 15/07/2026

Got me even though I knew it was coming

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Pekka Väänänen @pekkavaa.bsky.social · 15/07/2026

An update on this: I tried the DAG method of eastfarthing.com/blog/2016-05... but couldn't get it to work. I tried the C64 palette and the greatest distance found is between black and dark cyan. Using that distance to find neighbors connects many colors 10 others so its not useful for finding ramps.

eastfarthing.com

Mapping Pixel Art Palettes

While researching pixel art palettes, I noticed a lot of discussion about color ramps. I've come up with an alternative to crossword-style layouts.

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Pekka Väänänen @pekkavaa.bsky.social · 13/07/2026

Another good find from Bouman's image processing course: CIELAB DeltaE is intended for comparing larges swathes of color, not individual pixels. Source: engineering.purdue.edu/~bouman/ece6...

Warning: Don't Abuse Lab Space

Lab color space is designed for low spatial frequencies.
- It is very good for measuring color differences in objects.
- It is the standard for measuring paint color.
- It is good for measuring color accuracy of printers and displays.

Direct application to images works poorly.
- Lab does not account for high spatial frequency content of images.
- Lab formulation ignores different form of CSF for luminance and chrominance spaces.
- Image coding in Lab space will produce poor results.

C. A. Bouman: Digital Image Processing - January 11, 2026

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Pekka Väänänen @pekkavaa.bsky.social · 13/07/2026

Useful dithering (digital halftoning) related notes: engineering.purdue.edu/~bouman/ece6... They are from Charles A. Bouman's Spring 2026 "Digital Image Processing I" course, Purdue University.

engineering.purdue.edu

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Pekka Väänänen @pekkavaa.bsky.social · 10/07/2026

I just read about it recently. I think it's beautiful that the printing community has given it such a cute name. Discovering that combination of angles must have been a relief😅 I've also heard that yellow is sometimes printed using some sort of dithering while other inks keep the clustered-dot shape

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Pekka Väänänen @pekkavaa.bsky.social · 09/07/2026

I've read that newspaper-like halftone patterns are laid out in a 45-degree angle because the human eye is less sensitive to that than to straight grid lines. But wouldn't a simpler explanation be that newspaper photos of streets and buildings have straight lines, so a rotated pattern works better?

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Pekka Väänänen @pekkavaa.bsky.social · 08/07/2026

www.indiegamemusic.com used to be a thing way back and looks like they are still in business

indiegamemusic.com

Indie Game Music

Bringing music artists and game developers together

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Pekka Väänänen @pekkavaa.bsky.social · 08/07/2026

The Mona Lisa mapped to the Commodore 64 palette by taking only pixel lightness into account. Two algorithms: N-Convex (left) always tries to dither the result while in Knoll's algorithm (right) dither strength can be tuned.

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Pekka Väänänen @pekkavaa.bsky.social · 30/06/2026

Thanks for the feedback. The phone-reading experience is not the best and you're not the first to notice this. I'm not sure what's the best option is. "First" and "second" feel strange when the images are side by side. Perhaps labels like (a), (b) etc. would be the most neutral?

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Pekka Väänänen @pekkavaa.bsky.social · 29/06/2026

A new article: Revisiting Yliluoma’s ordered dither algorithm 30fps.net/pages/revisi... It's a deep dive to a single "color selection algorithm" used for ordered dithering. Nothing groundbreaking but I did uncover a neat simplified version that works OK. It's technical but with visual examples.

A graphic showing a side-by-side comparison of three versions of the same image, each processed with a different dithering algorithm.
The image consists of three vertical panels arranged horizontally, with a text summary located at the bottom. Each panel features a stylized bird from the Big Buck Bunny animated short. A yellow beak and large eyes, sitting on a branch. A blue-to-pink gradient sky and green leaves in the background.

The three panels:

Yliluoma's 2nd dithering algorithm: Dithered result with the most noise.
EMA-Constant: Significantly smoother result.
Knoll (10% strength): Smooth result similar to EMA-Constant.

Text at the bottom:
Summary: This article discusses Yliiluoma's 2011 ordered dither algorithm (left), explains its internals in greater detail than other treatments, presents new simplified variants (middle), and compares the results to a state-of-the-art algorithm (right). Source code is included at the end.

A 2x2 grid comparing four versions of the same pixel-art scene from the 1999 Chrono Cross video game: three characters in a detailed interior room with curtains and windows. Each version uses a different dithering technique.

The images are labeled (top-left to bottom-right): "EMA-Exact", "EMA-Constant", "Knoll (20% strength)", and "Knoll (10% strength)".

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Pekka Väänänen @pekkavaa.bsky.social · 26/06/2026

Trying to finish a new blog post on ordered dithering. It's been _so_ much work but I think it's turning out really interesting.

A six-pane comparison of a Chrono Cross screenshot reduced to a 16-color fixed palette. Each pane shows a different result and they all are somewhat noisy. The panes are labeled EMA-Sweep, EMA-Exact, EMA-Constant, Yliluoma-2, Yliluoma-2 (no luma weighting), Knoll (30% strength).

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Pekka Väänänen @pekkavaa.bsky.social · 23/06/2026

Not too far from maximin (max coverage) algorithm that adds to a palette the image color that's furthest from the colors chosen so far. Its probabilistic version is the industry standard k-means++ init. So yeah sounds like a great idea and looks pretty too :)

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Ruben S. @atomicagegames.co.uk · 22/06/2026

Tried my hand at a 90s pre-rendered CGI aesthetic in Unity for a game jam #GameDev #IndieDev

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Pekka Väänänen @pekkavaa.bsky.social · 12/06/2026

That makes a lot of sense, it's the same clock both for memory reads and the monitor horizontal sync. Thanks!

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Pekka Väänänen @pekkavaa.bsky.social · 12/06/2026

My new hobby: Taking holiday photos with multiple exposures to create fake GDC slides afterwards.

A PowerPoint slide titled "Cathedral Church of Saint Vitus". There is a three-pane comparison images labeled "Direct and emissive", "Indirect diffuse (baked)" and "Final render (Xbox One)". The background color is black and at the bottom there's a grey text "Rendering Secrets of 'Pekka's Two Nights in Prague'"

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