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Lichtso

Re:We ran AI agent swarms in Minecraft and Mindustry on Sunday November 01, 2026 @12:43PM (#50327810)
"Turning Games" also has videos with that idea: https://www.youtube.com/watch?v=d7p1ACIyJW0
> Whether undoing transactions or not is an option strongly depends on how fast value is allowed to move. Sometimes being slow is a feature as much as it is a bug.

Exactly, that is my point. It is less about reversibility and more so about speed. Being slow can be an advantage (for security).

The reversibility of transactions is often brought up but I don't think that is the main differentiator, or any at all really.

First, both cryptocurrencies and traditional finance systems have chosen to and have chosen not to reverse or freeze criminal transactions in the past. Decentralized blockchains have chosen to do so at least once [0]. The traditional finance system has chosen not to many times and even large sums [1] [2]. It really comes down to how much is stolen and how much influence the victim(s) have.

No, instead I think the main difference is the speed of transactions. Some blockchains operate within milliseconds while bank transactions take days. Even instant transfers are actually settled on a way longer cadence in reality.

That means attackers can do a fast sweep on blockchains, which is not possible with bank transactions because everything happens in slow motion and humans have way more time to react and step in.

[0]: https://en.wikipedia.org/wiki/The_DAO [1]: https://www.turkiyetoday.com/turkiye/german-bank-e100m-disap... [2]: https://en.wikipedia.org/wiki/Bangladesh_Bank_robbery

Re:We ran AI agent swarms in Minecraft and Mindustry on Friday October 30, 2026 @11:36AM (#50305439)
The Youtuber "Emergent Garden" has run similar experiments in Minecraft, though with smaller swarms (if you can call it that at all).

https://www.youtube.com/watch?v=KxaPYhfJV4U

Re:Start Doing Graph Theory on Wednesday October 28, 2026 @06:40PM (#50281959)
You would be surprised how hard it is to visualize arbitrary graphs. Basically, we can only render small highly regular ones in a neat way. Everything beyond that turns into a ball of wool.

Graphs in general are high dimensional structures and don't lend themselves to 2D projections. That is not a problem with coding the layouting algorithm. There simply is no good geometric arrangement for most graphs / networks because they are not planar [0], or even close to it (with few intersections).

[0]: https://en.wikipedia.org/wiki/Planar_graph

Re:CERN and Mistral join forces to accelerate AI for science on Monday October 19, 2026 @01:32PM (#50155313)
It is.

What I think the parent post is missing is that breakthroughs in science don't immediately translate into breakthroughs in engineering and even less so into economically viable products.

Re:Two-Stack Sliding-Window Aggregation on Friday October 16, 2026 @12:11PM (#50120219)
If I am not mistaken a weighed fold / reduction [0] over a sliding window (kernel) is a convolution [1], right?

While the algorithm presented here is sequential, this smells like it could be done in parallel.

In fact the "cum_aggs" stack is a prefix scan [2].

For the sum of values (and by extension also the average), if you have the input prefix scanned (which can be done in parallel) then you can answer any (yes any, dynamic size, not fixed size window) subslice reduction in constant time.

[0]: https://en.wikipedia.org/wiki/Fold_(higher-order_function) [1]: https://en.wikipedia.org/wiki/Convolution [2]: https://en.wikipedia.org/wiki/Prefix_sum

Re:Vx – One Language, Every Chip on Sunday October 04, 2026 @04:52PM (#49957723)
Minus the NPU target, if you want Mojo in Rust there is https://github.com/tracel-ai/cubecl
Re:Loss of Cell Identity Drives Human Aging on Friday October 02, 2026 @04:24PM (#49938176)
There always has been a lot of stress, but there used to be relaxed moments as well. The issue is that we don't calm down anymore.

Relevant video by Kurzgesagt – In a Nutshell: https://www.youtube.com/watch?v=Mo1A45ShcMo

Re:NAND-16: a computer built from 277,248 NAND gates on Wednesday September 30, 2026 @07:18AM (#49907289)
LLMs are not like other tools. LLMs are running a model, and that model is just provenance / attribution washing on a unprecedented scale.
Re:iOS 27, iPadOS 27, and macOS 27 on Tuesday September 15, 2026 @03:11AM (#49708860)
On macOS you can delete them manually (though it requires booting into recovery mode and temporarily disabling System Integrity Protection).

https://github.com/tejyash/delete-apple-intelligence-macos

Re:Mojo is now open source! on Tuesday August 18, 2026 @12:49PM (#49348536)
Technically soruce available now with the promise of accepting contributions (thus becoming fully open source) early next year. But since it is an Apache 2 license (like the rest of the LLVM project) you are already allowed to fork and contribute to your own fork right now, just no upstreaming.

For many the closed source nature of the compiler was a knock-out criterion. We will see if Mojo can gain traction now or if it has missed its window of opportunity.

People often forget that architecture in (central and northern) Europe is build under the assumption that the climate has more cold extremes than hot extremes. Thus, buildings were constructed to both retain and collect as much heat as possible to save on heating in the winter. Now, if you just slap an AC onto that it will have to fight all of the passive heat collection. In other words, you would have to also close off all south facing and roof windows for it to work.

Furthermore, the way the last mile distribution of power works is often underground (with the cables directly in the sand, no hose or tube around it) which makes it expensive to upgrade to handle a much higher peak consumption. Only lucky thing is that you mostly need AC when the sun is shining, thus local production via photovoltaic cells is a good solution that sidesteps the power grid problem.

Re:Geometric Reasoning on Saturday August 15, 2026 @10:51AM (#49311076)
Audio glitches like the one at 45:15 (https://youtu.be/4S8I22ybG2c?t=2715) make me think even the interview video might be generated.
I am curious what kind of plasma is used, as there are many ways to create plasma under various conditions, with very different efficiencies, selectivity, yield, etc.

Among the worst is the Birkeland-Eyde process, hot plasma by electric arcing, like it happens naturally during a thunderstorm. Even microwaving the air is more energy efficient. And amongst the most promising are transient non-equilibirum / cold plasma approaches using ns pulse generators.

> the common usage connotation of “renewable energy “ today is “wind and solar”

Hydro, wind and solar. Hydro is often even more important because it runs more steadily than the other two.

Geothermal and nuclear are neither fossil nor renewable, they are their own category.

Re:A Decade of Slug on Wednesday March 18, 2026 @08:37PM (#47433240)
> [1] and [2] sound similar to what you are describing. They still involve triangulating the shape, but the triangulation process seems much simpler

Yes, they describe one variation of the angle based method to winding numbers by spanning a triangle fan from an arbitrarily chosen pivot point / vertex.

> if you want to do distance based anti-aliasing rather than supersampling

Particularly when it comes to rendering vector graphics I think of analytic anti-aliasing methods as somewhat cursed and prefer multisampling [0], at least for magnification. For minification mip-mapping remains the go to solution. However, if you only render 2D text on a 2D plane, which is typically overlap free, then these correctness issues don't matter.

> I don't see a straightforward way to apply this technique in a pixel shader that includes multiple curves per triangle

All modern vector renderers I know of avoid triangle rasterization entirely. Like I said, they typically do tiles (screen space partitioned into quads) in a compute shader instead of using the fixed functionality with a fragment / pixel shader. The reason is that nowadays compute is cheap and memory bandwidth is the bottle neck. Thus, it makes sense to load a bunch of overlapping geometry from global memory into workgroup shared memory, render all of it down to pixels in workgroup shared memory, and then only write these pixels back to the framebuffer in global memory.

> I feel like any attempt to do that will approach the complexity of Slug

A highly optimized implementation might very well, yes. Yet, handling the many cases of intersections of the path and the scanline won't be contributing to the complexity, which is what started this discussion.

> I would love to read more detailed information on that if you have it.

I implemented the outdated stencil buffer + triangle fan + implicit curves approach [1] if you want to take a look under the hood. The library is quite complex because it also handles the notoriously hard rational cubic bezier curves analytically, which Slug does not even attempt and just approximates. But the integral quadratic bezier curves are very simple and that is what is comparable to the scope Slug covers. It is just a few lines of code for the vertex shader [2], the fragment shader [3] and the vertex buffer setup [4].

Edit: You can even spin loop & blinn into a scanline method / hybrid: They give you the side of the curve your pixel is on [5], which is typically also the thing scanline methods are interested in. They compute the exact intersection location relative to the pixel, only to throw away most of the information and only keep the sign (side the pixel is on). So, that might be the easiest fragment shader vector renderer possible. Put it together in a shader toy [6] a while back.

[0]: https://news.ycombinator.com/item?id=46473247#46530503 [1]: https://github.com/Lichtso/contrast_renderer [2]: https://github.com/Lichtso/contrast_renderer/blob/main/src/s... [3]: https://github.com/Lichtso/contrast_renderer/blob/main/src/s... [4]: https://github.com/Lichtso/contrast_renderer/blob/main/src/f... [5]: https://news.ycombinator.com/item?id=45626037#45627274 [6]: https://www.shadertoy.com/view/fsXcDj

Re:A Decade of Slug on Wednesday March 18, 2026 @02:35PM (#47429594)
> It avoids the issue of a winding number by assuming there's only 1 bezier curve per triangle

The original paper did assume no overlap yes. But that is not how anybody would implement it. For a long time one would use the stencil buffer with different operations depending on the front-face / back-face (this is where the paths rotation around the sample comes in and what makes this an angle based approach).

> which requires a complicated triangulation step. It can produce some nasty geometry in more complex cases.

Again, not how anybody would implement this. You can just stream the quadratic bezier curves unprocessed into the vertex shader, literally the simplest thing conceivable.

> With Slug, you can use only 1 quad per glyph if you want.

Nowadays one would probably implement loop & blinn in a tiled compute shader too (instead of using stencil buffers) to reduce memory bandwidth and over draw. That way you also get one quad per glaph, but without any of the geometry special casing that Slug does.

> It's the breakdown into different cases that _solves_ those issues, whereas your statement makes it sound like slug has _both_ the case complexity and the precision issues.

Correct, might have worded that badly. Still remains a trade off in a) which b) does not have.

Re:A Decade of Slug on Wednesday March 18, 2026 @06:12AM (#47423711)
I think it is limited to integral quadratic bezier curves, which is sufficient for text rendering. But general purpose vector graphics almost certainly want rational cubic bezier curves too.
Re:A Decade of Slug on Wednesday March 18, 2026 @06:03AM (#47423665)
There are two ways to get winding numbers and then decide on filled or empty by some rule like non-zero or even-odd:

a) The winding number of a point is the number of intersections of a scanline and a closed path.

b) The winding number around a point is the total angle subtended by the path at that point.

Slug uses approach a) and that comes with a lot of edge cases (see chart in the post) and numerical precision issues. The approach by loop & blinn uses b) and is thus simpler and more robust. Likewise the patent on that one expired too: https://news.ycombinator.com/item?id=47416736#47420450

John Lin used to work on such an engine where all voxels stay axis and grid aligned, even in animations:

https://x.com/ProgrammerLin/status/1342786223811698688 https://voxely.net/blog/

But I think the project was abandoned in 2021.

Re:Turn Dependabot Off on Friday February 20, 2026 @07:27PM (#47096053)
> I Think that DoS needs to stop being considered a vulnerability

Strongly disagree. While it might not matter much in some / even many domains, it absolutely can be mission critical. Examples are: Guidance and control systems in vehicles and airplanes, industrial processes which need to run uninterrupted, critical infrastructure and medicine / health care.

Re:Art of Roads in Games on Monday February 09, 2026 @11:33AM (#46947222)
Really depends: In some areas it is quite advanced (rendering) and in others it is lacking / underdeveloped (editors / tooling). But there is an incredible amount of progress and also churn in keeping up with that.

https://thisweekinbevy.com/ https://bevy.org/news/

Re:Art of Roads in Games on Monday February 09, 2026 @05:17AM (#46943631)
> The thing is that I myself don't even know what I want to do with it.

Embrace the next challenge: Instead of roads on parabolic (Euclidean) geometry, have roads on elliptic (non-Euclidean) geometry, like the surface of a sphere. Plus, on a sphere every line is already a circular arc anyway (no matter if straight or bent, the difference is just the center, radius and normals). Thus, this system of circular arc segments really lends itself to such a space.

Little prince style micro planets with their own miniature infrastructure will always have a special place in my heart. Half a year ago I started with laying out the basics https://github.com/Lichtso/bevy_ellipsoid_billboard https://github.com/Lichtso/bevy_geodesic_grid but got distracted by fixing some engine bugs in Bevy along the way. That reminds me I have to update to the newest engine version ...

anyway you can find some of the roads on spheres stuff here: https://github.com/Lichtso/bevy_geodesic_grid/blob/main/src/... it can not only generate the extrusion mesh but also calculate how the mesh overlaps with a geodesic grid of triangular tiles on the surface.

Another point in case: Life only exists in liquids, not in solids (too much structure) and not in gases (too much chaos).

In fact one could argue that this is a definition of an interesting system: It has to strike a balance between being completely ordered (which is boring) and being completely random (which is also boring).

Re:Math of Vector graphics on GPU, inspired by piet-GPU on Wednesday January 07, 2026 @01:34PM (#46530503)
> but [analytic anti-aliasing (aaa)] also has much better quality than what can be practically achieved with supersampling

What this statement is missing is that aaa coverage is immediately resolved, while msaa coverage is resolved later in a separate step with extra data being buffered in between. This is important because msaa is unbiased while aaa is biased towards too much coverage once two paths partially cover the same pixel. In other words aaa becomes incorrect once you draw overlapping or self-intersecting paths.

Think about drawing the same path over and over at the same place: aaa will become darker with every iteration, msaa is idempotent and will not change further after the first iteration.

Unfortunately, this is a little known fact even in the exquisite circles of 2D vector graphics people, often presenting aaa as the silver bullet, which it is not.

For everybody claiming that locomotion without the impulse of a reaction mass is impossible: https://arxiv.org/abs/2112.09740v2

and before anybody only reads "spacetime curvature" and thinks the paper is talking about a warp drive, it is not.

Anyway, this Genergo thingy seems to be nonsense IMO, or they would have actually explained how it works.

Re:Game design is simple on Friday November 07, 2025 @06:35AM (#45845434)
> I honestly cant't think of any good examples where game mechanics and stories interacted in a way that gave you significant agency while still being fun. I'd love to be given contra-examples though.

Rimworld and The Sims. Both are procedural story writers.

> I felt railroaded into comically absurd black/white choices

I agree: All these AAA titles essentially are movies where you get tons of "agency" in choices which are irrelevant to the story, but the main plot is hard scripted into a few predetermined paths.

Until we have full generative AI as game engine the only alternative remains the procedural approach mentioned in the beginning.

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