Lefteris Stamatogiannakis

BeamNG CTO. Physics, programmer (Rigs of Rods, BeamNG). Database and big data researcher (University of Athens).

[Lefteris Stamatogiannakis @estama2]

To @EU_Commission ,
This is a contemporary photo of a 3000 years old board game from Ramnous archeological site in Greece.
We are members of @videogames_EU and we support @StopKilingGames .
Games *are* cultural heritage.

[Lefteris Stamatogiannakis @estama2]

@DanielcHooper Nice work :). If you are interested in a simple GPU accelerated, vector based font rendering method: https://t.co/5fgvs6rd9z

[Lefteris Stamatogiannakis @estama2]

New font2curves. The previous uneven bezier implementation, based on @iquilezles formulation had numerical edge cases and wasn't accurate enough. These are fixed with the new formulation, the fonts look a lot better with the new primitive:
https://t.co/HMoflPbwNn

[Lefteris Stamatogiannakis @estama2]

In BeamNG we like textual formats because they are nice for moding. We also like performance, so we spend time to optimize working with them.
A talk on fast JSON decoding in FOSDEM 2026 by Adam Ivora showcases some of that work:
https://t.co/rWNo8LIj6H

[Lefteris Stamatogiannakis @estama2]

@JKoukourakis Yes physics is custom made, on the CPU. GPU is mainly for the visuals. For that kind of physics performance, you need to design around the physics, including the rest of the game engine. For example we need the CPU cores for the physics, so GE takes what remains.

[Lefteris Stamatogiannakis @estama2]

@JKoukourakis We do use fixed dt physics in BeamNG, but only when absolutely needed, as our physics runs at 2Khz steps. Everything else we try to have it on variable dt stepping.

[Lefteris Stamatogiannakis @estama2]

@JKoukourakis The more calculation "mass" in the variable step, the better the fps stability. I would pick a variational integrator (they work well with variable dt), and impose a maximum physics dt limit, if the actual dt was bigger than the limit, i would subdivide the physics dt.

[Lefteris Stamatogiannakis @estama2]

To remind, font2curves converts fonts to a list of uneven bezier curves* which can be directly rendered on the GPU. No atlases or fancy font rendering techniques required.
*I provide the uneven bezier curve shader within font2curves

[Lefteris Stamatogiannakis @estama2]

New font2curves. The previous uneven bezier implementation, based on @iquilezles formulation had numerical edge cases and wasn't accurate enough. These are fixed with the new formulation, the fonts look a lot better with the new primitive:
https://t.co/HMoflPbwNn

[Stephen Zimmerman @PastorSZ]

My 12 year old son wanted a gaming wheel for his racing game @beamng but couldn’t afford one…so he spent all day yesterday building his own racing wheel out of cardboard.
He asked me post it here for @LogitechG to see since he’d love to one day have a Logitech G923. Enjoy!

[Lefteris Stamatogiannakis @estama2]

Above is based on: https://t.co/JeTUvWZVUm from @iquilezles

[Lefteris Stamatogiannakis @estama2]

In continuation from my previous post, here is a font to quadratic curve converter that goes from TTF to quadratic curve primitives. This enables simple font rendering completely on the GPU:
https://t.co/ofNCgrVOQk

[Lefteris Stamatogiannakis @estama2]

For GPU accelerated font rendering, use this SDF primitive: https://t.co/GbkLcQwdgP

[Lefteris Stamatogiannakis @estama2]

I was ill and couldn't focus, so i've decided to learn vibe coding by writing a True Type Font to center lines converter using Gemini 3.
This can be useful for GPU font rendering without an atlas. Just draw the lines/SDF_capsules
https://t.co/aZKJxVKjkd

[Lefteris Stamatogiannakis @estama2]

It can also be useful for cases where Hershey fonts are used, such as CNC machines and so on.

[Lefteris Stamatogiannakis @estama2]

@panoskarabelas Slip angle/ratio calculation is unstable at low speeds, and at exactly 0 speed it is undefined.

[Lefteris Stamatogiannakis @estama2]

@panoskarabelas I would also have added a warning in presentations of the Pacejka magic formula, that it has problems at low speeds. There are different approaches on how to account for that, including what we do (we don't use it).

[Lefteris Stamatogiannakis @estama2]

@panoskarabelas It is a nice article, but be warned there are still (at a quick glance) things missing such as tire load sensitivity and so on.

[Lefteris Stamatogiannakis @estama2]

@LowRezHD @videogames_EU I expect a corporate lobbyist organization to not be harming their members. Their position would end up with nobody buying games because they wouldn't understand what they are buying. If trust destroying behaviors are normalized, then it'll affect everyone.

[Lefteris Stamatogiannakis @estama2]

BeamNG is a member of @videogames_EU . VGE didn't ask BeamNG concerning their response to https://t.co/5MN8gBDo6u . As far i know there wasn't a vote on this too. We do NOT agree with their statement, this is not how a representative group should be behaving.

[Lefteris Stamatogiannakis @estama2]

If it isn't clear why @videogames_EU statement is problematic for all companies. Their position allows a sale to be fully destroyed at a future time including right after someone bought it. This kind of positions destroy consumer trust, and leads to consumer protection laws.