Several SPH/N-body simulation with black holes, simulated using SpaceSim, a software I'm developing.

The Mediterranean runs at a loss: it evaporates about 0.5-1 m of water level per year more than rain and rivers put back, and the Atlantic covers the deficit through Gibraltar around the clock. My simulator derives a 0.7 m/yr deficit on its own from its climate model - right in the textbook range - so I felt entitled to do something irresponsible with it.

I sealed the strait (14 km wide at its narrowest) and let it run. No scripted animation - every cell tracks its own evaporation, precipitation and river inflow each year, and global water volume has to conserve to within 2 parts in 10,000.

Timeline:

- 25 years: level down 17 m. Venice's gondoliers are the first out of work.

- ~500 years: the Adriatic is gone (average depth only 250 m).

- ~700 years: the Sicily-Tunisia ridge surfaces and the Med splits into two shrinking lakes. When this actually happened 5.97 million years ago, hippos walked to Cyprus - their stranded descendants shrank into dwarf hippos. The fossils exist.

- ~2,100 years: the basin is effectively dead. 2.5 million km² of new land, nearly the size of Argentina, crusted with precipitating salt.

- ~4,300 years: the deepest pools bottom out. Except one - a bitter lake in the east kept on life support by the Nile. I never coded that; evaporation, rivers and terrain balanced it into existence on their own.

The Black Sea survives: once its level drops below the Bosporus sill it detaches and holds steady on the Danube and Dnieper. The Caspian was my control group - untouched, it drifts 17 m in 300 years and then stabilizes.

This genuinely happened. It's called the Messinian Salinity Crisis: 5.97 million years ago Gibraltar really did close. In 1970 the drillship Glomar Challenger pulled gypsum and rock salt out of the Mediterranean seafloor under 3,000 m of water. My simulator has never heard of the Messinian - it just agrees with the drill cores.

It's all from a game I'm building where you do this with a brush. Link in the comments to keep things tidy.

I couldn't find a tag that fit so I just picked Proprietary, but I made it in Unity.

Edit: because people have a lot of really good questions, I'm adding the link for the longer video here: https://www.youtube.com/watch?v=TIdHDe0JUpw&lc=UgyLw_Z8QZ-GH2CSxRp4AaABAg . This should answer most questions, and I'm super happy to answer any that it doesn't!

This is a prototype of a game idea that I have been poking at for many years. It's a dynamic character that moves like an amoeba, eats things in its environment, and grows by incorporating them into its body.

It is completely procedural, implemented as a particle system with flows and body-shaping forces driving the formation of pseudopods that move it along or cause it to ingest items. It uses a custom physics engine that executes the flows and allows the creature to interact with other entities in the world. It took quite a bit of experimentation to get something that (I think, anyway) looks lifelike, and I hope to improve it. This first game level is just a proof of concept with minimalist styling, helping me build out some tools.

A short video trailer is linked to this post and you can play the prototype game at https://eatthepeople.com

For this crowd I'll mention that if you add the url param "debug=1" you can see the full debug view and mess with the params that drive the creature. In debug mode shift-clicking teleports him so you don't have to play through the entire level to get somewhere.

All feedback welcome!

I'm working on this destruction focused imsim that's like Falling Down meets wall-e. I put a lot of effort into making the bat respond physically accurately to surfaces and collisions. the game will also have walking and balance simulation for characters with legs.

https://x.com/Fleech_dev/status/1923027152716411005

Hi, I'm back here again to answer the most popular questions from the last post. This time, I included a voiceover to explain a bit better what's actually going on here. I'm not sure if this type of post is allowed, so if there's somewhere else I should be posting this please let me know!

As before, if you want a more comprehensive crash course in 4D, please check out my full video on the subject: https://www.youtube.com/watch?v=TIdHDe0JUpw

This runs live on an Apple silicon GPU.

Every bird reacts only to the ones near it. Nothing choreographs the shape and nothing is keyframed, so what you are watching falls out of 137,500 of them following local rules at once.

It is a GPU flock on an atomic spatial hash, which keeps neighbour lookups linear instead of quadratic at that count. Each bird steers on a bounded turn rate and banks into its turns, and the banking is what makes the flock flicker as they roll.

Based this on starling literature rather than plain boids, mostly Cavagna's work on scale-free correlations in real flocks and Couzin on spatial sorting. Cool thins is that the same system with one flag flipped runs a bait ball instead: change the attractor from polarised streaming to milling and the sheet becomes a rotating sphere.

Built in Swift and Metal as part of TideGlass, a small Mac app I make where worlds like this run on a second monitor while you work. Happy to answer anything about the sim.

This video is from 2020, from our sandbox voxel simulator called BFS. It was running back then in Unity 3D. It took us another 6 years to make that scene multiplayer

Nagel-Schreckenberg simulation. Made in TouchDesigner

Hello there! I wanted to make a larger scale simulation to see if my simulator, Galaxy Engine, could handle it. And it did! After 12 hours of simulation I got this result. As you can see, there are some artifacts like the rings that form at the beginning, but the simulation didn't crash.

You can find the source code and also download Galaxy Engine from GitHub: https://github.com/NarcisCalin/Galaxy-Engine

You can also buy it on Steam if you want to support the development: https://store.steampowered.com/app/3762210/Galaxy_Engine/

And you can join the Galaxy Engine community and talk about space and programming here! https://discord.gg/Xd5JUqNFPM

No, not a joke, but my newest hobby horse project. I'm no longer sure if I'm mad or just happy - here is the GitHub repo: lifehashes

spatial partitioning, instanced rendering, multi threading