a-d.s - projects

Digital art

2025-08-19T00:00:00+02:00

proc.gen

2025-08-19T00:00:00+02:00

Draconic space monorail (p5.js)

Stellar ticket

2025-08-16T00:00:00+02:00

About#

I had access to a ticket printer, so I played around and came up to some kind of "modempunk stellar system detector output".

I used a list of latin words from wikimedia that I pre-processed. The printer spat some questionable names pretty quickly.

Files:

[stellar_system.py] [requirements.txt] [latin.csv]

Elben

2025-08-14T00:00:00+02:00

Content

History
Physical effect on Earth
Moon cycle
Exploration
Life
Altitude numbering

Elben, as seen from earth during the day

Elben is an ice giant and the third planet in our solar system. It is home to three major moons, including the Earth, the biggest among them, which is in quasi-orbit with Luna or the “Moon” itself, providing a sort of natural satellite to the Earth.

It has a mass of 1.024 × 10^26 kg, and a radius of 24,622 km. As such, it has a gravity relatively close to that of earth at 1.14g. It’s situated 1.795 x 10 ^ 9km from the barycentre of the solar system.

Scientist believe that Elben formed when binary system was weaker, then the habitable zone reached it, which would explain why an gaseous planet with volatiles such as methane, ammonia and water would be so close to its home stars.

Its name is sometimes written as “Elbin”.

History#

Elben is for obvious reason, the first planet to be “discovered” in the solar system: it is clearly visible in the sky during the day, and sometimes creates crepuscular nights every time the earth passes behind it.

<<>>

Grey mother

reading future in shape of clouds

Physical effect on Earth#

Among other things, Elben first and foremost effect are the eclipses: every 17 days approximately, the Earth is obscured by the planet which, depending on when during the day-night cycle is, can either creates mid-day nights lasting a few hours or nothing at all. These nights are characterized by slight greenish tints when transitioning to those nights due relatively colorless composition of the atmosphere of Elben and some impurities.

The second effect is its magnetic field: as Earth magnetic field is relatively weak, and getting weaker as time passes, Elben’s one is the only defense against the powerful solar winds which its the system and might kill all life on Earth.

Its mass also has a impact on tides, yielding a double-cycle tides with the moon. During “constructive” cycles, tides are stronger, or might barely happen during “destructive” cycles; conversely, the constructive tides might be more destructive to the ecosystem and to humans.

It is speculated that part of Earth’s life might have been sowed from Elben, given its large discrepancies with the rest of the tree of life.

Moon cycle#

Due to the moon being in a resonance orbit with the Earth, acting as a quasi-satellite, the Moon cycles and Elben’s cycles are synchronized and opposite.

Exploration#

Up until the 1960s, very little was known from Elben atmosphere. While its general composition and structure was known, everything was observed from Earth’s ground, and satellites were barely providing better data. But in 1965, Elba II, following the first iteration failure, successfully orbited around Elben before being thrown away from the system by a unplanned gravitational swing. Later that year, Elba III successfully dove into the ice giant atmosphere, providing confirmation of the atmosphere composition before burning up.

![screenshot102.png](https://prod-files-secure.s3.us-west-2.amazonaws.com/d1082c5a-c804-4fd4-bc91-aa51bbe5d809/9c9c93c9-bc79-48ee-a1d5-e7e3630786cd/screenshot102.png)

Elba II before integration

Elba IV has known a similar fate. In 1966, Elba V attempted to skim the atmosphere but burned before leaving it and fell deep into its core. Finally in 1967, Elba VII, following Elba VI scrubing due to manufacturing error, skimmed the atmosphere at a relative height of 120km, before leaving the planet and transmitting valuable data.

The Oncro Exploration Program (OEP) sent a probe that same year, which slowly dove into the core while sending data to an orbiter. Six other probes were sent, and Oncro 3, 5 and 6 sent pictures of actual life in Elben atmosphere: countries around the world have since promised exploration programs to investigate further, following the cultural shock of discovering life on another astral body.

![Elba III last photograph](https://prod-files-secure.s3.us-west-2.amazonaws.com/d1082c5a-c804-4fd4-bc91-aa51bbe5d809/21f6b0e1-e866-467c-82f1-3af2ad5322db/screenshot105.png)

Elba III last photograph

Speculations of human missions have been made, including within the atmosphere. However, the cost of sending a whole launcher to allow for return of the astronauts has been prohibitive so far. Several Spatial agency have speculated on building a space station around Elben, including possibly through international cooperation.

Life#

![life_elben.kra.png](https://prod-files-secure.s3.us-west-2.amazonaws.com/d1082c5a-c804-4fd4-bc91-aa51bbe5d809/c3407de4-961d-477b-90a1-3f33cd2d4f5b/life_elben.kra.png)

[Elben’s life and exploitation](https://www.notion.so/Elben-s-life-and-exploitation-3a0fedb567734bcfb6410f2c8c9d5e2b?pvs=21)

Altitude numbering#

Altitude is based around the typical altitude at which the pressure is equal to that of earth, and dealt as a “depth” : above level altitude numbers are negative and below as positive

<<issue with reaching core, but like earth, theorical>>

[AGE OF THE INTREPIDS: skimming Elben Atmosphere ](https://www.notion.so/AGE-OF-THE-INTREPIDS-skimming-Elben-Atmosphere-7c60dc30563441edad71ff78739fa9f1?pvs=21)

[Elben colonization](https://www.notion.so/Elben-colonization-bff42a648f1f4713bbf2600f75b259a1?pvs=21)

Planetary system

2025-08-05T00:00:00+02:00

This article is still a work in progress.

The Aper-Elvow system is the stellar system, currently home to the human civilisation.

Structure#

Aper-Elvow binary#

The system revolves around two stars at its center. The main star, Aper, is a a F-type main-sequence star, with a mass of 2.32×10^30 kg and a radius of 1 239 485.2 km. Its companion, Elvow, is a brown dwarf, orbiting a barycentre contained within the main star. A large plasma arc with variable intensity links the two bodies.

Each star center being at 0.04AU (from real earth value) from each other, with an orbital period of four (earth) days.

data	value
mass	1.13
radius	1.78
age	6.60 Gy old
surface temperature	5180F
rotational period	46 days
roche distance	6.61

Pora#

More details to come

0.09 Earth mass

Uroti#

More details to come

dwarf planet, 0.003 Earth mass, elliptical orbit

Elben#

Detailed article about Elben

It has a mass of 1.024 × 10^26 kg, and a radius of 24,622 km. As such, it has a gravity relatively close to that of earth at 1.14g. It is approximately situated 1.795 x 10 ^ 9km from the barycentre of the solar system.

sometimes written Elbin

2 AU, mass of 1.024 × 10^26 kg, 2.57 years (938.6925 days) orbital period

Major moons:

a small moon (0.00506 AU, 1.67 orbital period, 0.018 earth mass, 0.378 radius)
earth (harmony lock with large moon, faking orbital around) (0.0244 AU, 16.3 days orbital period, 1 earth mass, 1 earth radius)
typical moon

asteroid belt#

More details to come

Julvenel#

Mass: 4.867 × 10^24 kg, distance to barycenter 4.00 AU
Heavy atmosphere
used to be in habitable zone, and has trace of civilisation and still some life, like risk of rain planets ambience

Kabor#

rings deformed by large elliptical moon
large moon

icy asteroid belt#

More details to come

Aro#

More details to come

Paro#

More details to come

Tranulk#

rings
earth bis, 0.7 earth mass, 0.003 AU from neptune
Europa (subsurface ocean)

Europa exploration

Erfartris#

More details to come

large rocky planet

kuiper belt#

More details to come

Astronomy

2025-07-31T00:00:00+02:00

Origin and myths#

During ancient times, as nomads were legions. oracles were speaking of a god seeking its people. It was said, massive, heavy and also described as "one who moves very little" (translations vary among tribes). Yet, The prophecy narrated that "moving" it would be the challenge for its people, and that those who would have participated to its rise through history would be rewarded accordingly. As noamds were roaming, they found a geological anomaly: a huge rock which was roughly rhomboidal, sitting in the middle of a valley. Scientifically speaking, it is an iron-type meteorite which crashed on earth approximately two billions years ago, creating the said valley. It got submerged by the lands as erosion from near by mountains drained sediments, and reappeared when the bassin actually "re-opened" to the oceans through that same process, leaking the sediments over the course of millions of years. It is believed that due to the intermediary stages, as rain accumulated, it would also be the "black island" known in ancient texts from other civilisations. The Nomads settled nearby, and thus started the rise of Oplmek, city of the Great. We know very little on how long the task of raising the artifact took, but it probably went through several milleniums. We also ignore the actual process(es?) that got involved, nor the exact mass, as the rock extends below the surface. Those doubts led to a trend in geology and archeology that the stone was actually already vertical when it crashed, and only got revealed as the sand got drained from the bassin. An unknown regent would have then pretended that it was the act of his people to impose his power over the surrounding nations. This theory is quite popular as it is still compatible with the "black island" event, and is heavily backed up by the fact that the only traces of history around this miracle are oral tales and ancient reports from across the continent, but not from the site itself. This is the origin of a still ongoing religion known as "Uô".

Organisation#

The main church lies on top of the Rock, in the High District. For centuries, disciples were asked to reach for that sacred temple by climbing the various structures around the rock, including the growing city. It led to a hierarchy based on which path one used, as some were harder than others. A well known path was the South Face of the rock, which was the easiest and was basically very rough stairs created by farmers to access millenials trees that started to fracture the rock and grow. It is known nowaday as a plain but challenging hiking path. The North side, which is so inclined that it is actually tilted down, is the origin of a legend of "Hakan' Bil"; he or she was for centuries the only person who succesfully climbed that side. "Hakan' Bil" is now the title of the highest rank in the organisation: because of the original way of reaching that rank, there may be several Hakan' Bil at one time, or none. Nowaday, the process for reaching ranks is way more classical, through evaluation of the commitment of one and votes from "Uoas", the members of the cult. The church displays a rather atypical structure: it is composed of a black main tower situated in a corner of the top of the rock, from which extends a triangular roof covering the main room for the ceremonies. Under it, each disciple has his/her attributed place. The rest of the surface is occupied by the housing. Despite being a cult based upon a high place, the most prestigious quarters, inhabited by the highest ranks, are suspend houses on the East side of the Rock. The lowest suspended house used to be a prison which contained a garden, prisoners being used for the harvests. This task is now reduced to the maintenance of the now ornemental garden, which is done by the elders.

A word on Oplmek#

The city was for a long time mainly known as a religious hub: a fair part of the city's incomes was from an luxury alcool made out of the milleniums trees growing on the South side of the rock. Some wood could be found on the grey market as magical artifacts, but it was mainly kept for the Uoas as prt of a deal with the city for the inconvenience caused by the culture. The city now also include a lot of modern buildings, including the Iris, highest tower of the city and unavoidable element of the city skyline with its white colour. Some of those towers are build on the side of the huge rock, and the prices for the flats which have an adjacent wall with the Artifact skyrocket. Due to the sand retained, the main city is on a small hill: the rest of the valley is composed of farms, separated from the city by the historic wall. The mill which feeds the fields (and which uses bassins to retain water) is one of the oldest buildings of the city. Its conduct also now support the funicular for the tourists, and the rest of the path is made through a via ferrata.

The fall#

Today status#

As of today, three persons in the city's council defined themselves as Uoas, and its influence even affects general public culture through various references to a "black-ish monolith" of unknown power. Yet, it is mostly considered as folklore rather than a religion. The meteorite itself is considered as the potential source of life by some scientists: analysis shown very high rates of organic materials deep inside the monolith, even if we are unable to explain how a meteorite could contain such traces. This status is mostly what maintains Uô in the collective memory, even in a mostly atheist civilisation.

![uo_cult.jpg](https://prod-files-secure.s3.us-west-2.amazonaws.com/d1082c5a-c804-4fd4-bc91-aa51bbe5d809/0e6c8989-a3c0-457b-bff9-dad2f95a476d/uo_cult.jpg)

3700

2025-07-29T00:00:00+02:00

Astronomy#

Astronomy

Where Elben and the earth are, and all that jazz

Planetary system

The planets around us

I've been working here and there on that worldbuilding project for quite some time. It's still a Work In Progress, and will probably always be. The stories coming out of it aren't set in time for now, as the timeline has yet to be defined.

Elben's system#

Elben

Our grey mother's guts

Elben's life and exploration

When we dived down

CALENDAR HERE

In this setting, the Earth is a moon of Elben, an ice giant, exceptionally situated in the habitable zone. Itself orbit a binary star system composed of a fairly standard G2V star with a brown dwarf companion, a pretty common configuration in the universe. Earth still has a moon in the form of a quasi-moon in an harmonic orbit with it.

The history is still a work in progress.

Tales#

Draw Together (Summer) : "Méduse aérienne (rouge)"

Elben. La "mère grise" habille nos ciels depuis l'éternité ou presque : alors que la conquête spatiale était à ses balbutiements et les techniques encore peu sûres, il n'aura pas fallu longtemps […]

Too much sky for a pilot

You leave what little ground you had: you better not look down, even if you don’t fear heights. Heights have meaning. Here, nothing makes sense. The sky really is, limitless. It’s too much sky for a pilot.

the Uô cult

[…] disciples were asked to reach for that sacred temple by escalading the various structures around the rock, including the growing city. It led to a hierarchy based on which path one used […]

Svar Cheese Agreement

[…] On October 19th, the Svar Cheese Preservation Symposium came to an agreement to reinject an external strain, despite the protectionism that fought against it for decades […]

Monos class vessels

[…] operated by a limited crew, as steam-power was used to activate the sails and other subsystems. "Monos class" was a lose marketing term which designated ships from various sizes […]

Moved

2025-07-29T00:00:00+02:00

This page has been moved

This page has been moved here because I'm an idiot who can't maintain a consistent structure.

Moved

2025-07-29T00:00:00+02:00

This page has been moved

This page has been moved here because I'm an idiot who can't maintain a consistent structure.

too much sky for a pilot

2024-08-01T00:00:00+02:00

That’s too much sky for a pilot: discussion with commended pilot Johr Stirflar

Giant clouds bigger than the earth are rolling in the sky. Weather fronts so big and slow we map them. The war still rages between the three nations in the sky of our Mother Elben.

« I was doing surveillance around Etra’s cyclones when two unknowns showed up: they were fast. planes that high usually don’t go so fast: I knew it was Etrenian high altitude interceptors ». Our hero of the day, Sft. Johr Stirflar, was aboard a BX-100 fighter, a versatile but aging machine. Unfortunately, high altitudes aren't its forte, unlike Etrenian 10-atm specialized fleet. « I knew I couldn’t flee, so I dove to get some advantage. I first thought they didn't see me, but they quickly banked right and shot long range missiles. I barely had time to dodge that my craft burst into flames.

I spent eight hours reflecting on my life, alone in that space raft

THEY CALL IT THE DEEP DIVE. Getting shot down is the bane of the grey skies’ pilots, even more so than the ones on our planet: you are left with no choice but to separate you cockpit from your plane, and to hang below a parachute for hours on end. your only hope is that the rescue team picked up your distress call, as the sky around you gets darker and darker. « It was a long wait. You’re looking downward, with your low frequency antenna reaching far into the depths. At times, it looks like a tether pulling you towards the core of the planet »…. War treaties prevent from shooting down rescue battalions and downed crafts, but those are just cordial agreements between countries which are formally at war. Nothing would prevent one from violating that rule, other than the risk that others would do the same. « I spent eight hours reflecting on my life, alone in that space raft. I was at -80.000m from one-atm, things were getting hot. Literally. […] All of a sudden I heard radio chatters, and then saw it: the “whale”, a large vessel, half-floating half flying, with its hooks on its belly. I was finally saved. »

TOO MUCH SKY FOR A PILOT. Johr long described how the sky feel there :

[…] I spent five years in the 3rd deployment battalion here on earth. We would launch on so called long range missions, flying for 24 hours at a time. The sky felt limitless: horizon on end. Except, it’s not: it starts at the ground, and stops however high conventional planes can go. On Elben, It’s just air all around you. Every time you sortie from the carriers, you leave what little ground you had: you better not look down, even if you don’t fear heights. Heights have meaning. Here, nothing makes sense. The sky really is, limitless. It’s too much sky for a pilot.

Since the start of the war two years ago, following territorial issues around the 3000km long Arl skywall which flanks the Sea of Felz, 32 pilots got lost to the depths.

Pilots love to tell stories at the cantina of how it feels crossing the Ash Line. But if they’re here to tell, they didn’t crossed it […] You automatically get a commendation for doing the dive. Not that its something to be proud, but the brass knows you joined the rank of a very special kind of pilot: one who fears what’s below and won’t get hotheaded.

Sft. Johr Stirflar is scheduled to go back to the frontline later this year: everytime you look at Elben’s gentle grey crescent at night, think of those pilots braving the dark depths for the glory of our nation!

— Jonathen Golduque, correspondent on Air Station Polm II.

Monos class vessel

2024-07-28T00:00:00+02:00

The Monos Class Vessels were sailships used for less than a decade to transport fret and sometimes passengers across the xxx ocean. At the dawn of the second industrial revolution (note: the first being mecanical parts), the coal extracted from xxxx's mines was so poor that it could hardly be used for heavy-duty. before the development of better rafinery processes, coal was used as an auxilliary power to existing systems. Monos class vessels were sailships which were operated by a limited crew, as steam-power was used to activate the sails and other subsystems. "Monos class" was a lose marketing term which designated ships from various sizes: But as the steam-powered engines was barely viable enough even for this purpose, secondary ships were used to supply the biggest mastodons with fuel in the middle of their journey. The were also using the most of their enormous gear system to generate sufficient torque. This led to a short revivial of sea-crimes, where thieves would disguise their ships into refuelers to attack the cargos. In response, transport companies set a complex system of horns to allow medium-range (3 to 10 kilometers) communication and identification through chord-based codes. Musicians with perfect pitch were often hired to palliate to the cost and reliability of the rudimentary mechanical frequency-analysers. More than once actual refueling ships got sent to the bottom of the ocean by the cargos' cannons due to the approximate tuning of their organ.

Because they were often hiding in the coal wearing black clothes, and as most of their criminal empire revolved around the selling of coal in alternate markets, the "<coalers>" were humorously calling their business the "actual black-market". Monos Class ships quickly became obsolete, not only because of the improvement of coal-extraction, but also because of the terrible cost of their maintenance, especially the frequent replacement of the boilers that were diving in the sea, and which would accumulate salt on their tubes.

The Svar cheese preservation Symposium agreement

2024-07-28T00:00:00+02:00

In the year <<equivalent to 1900?>>, the infamous Svar cheese produced in its native region was suffering a genetic crisis. The ferments used for its production being constantly extracted from the same culture, its genetic diversity was in freefall and now threatening its viability. On October 19th, the Svar Cheese Preservation Symposium came to an agreement to reinject an external strain, despite the protectionism that fought against it for decades. On that fateful day, the Minister of Food Safety dumped the new strain from a becker into the tank, surrounded by researchers and journalists, fight to take a picture of that somewhat historical moment.

the Uô cult

2024-07-28T00:00:00+02:00

Origin and myths#

Organisation#

A word on Oplmek#

The fall#

People living in the High District and in the vertical suburbs started to complain of the growing number of people esacalading their houses and destroying the precious trees. Because of that, it was decided 50 years ago by the city council to build an elevator on the West side. The goal was to ease the access to the religion and thus the influence of the city. Today's Historians are still fascinated of how a simple and concrete structure induced the fall of such a major religion. ##Today status As of today, three persons in the city's council defined themselves as Uoas, and its influence even affects general public culture through various references to a "black-ish monolith" of unknown power. Yet, it is mostly considered as folklore rather than a religion. The meteorite itself is considered as the potential source of life by some scientists: analysis shown very high rates of organic materials deep inside the monolith, even if we are unable to explain how a meteorite could contain such traces. This status is mostly what maintains Uô in the collective memory, even in a mostly atheist civilisation.

![uo_cult.jpg](https://prod-files-secure.s3.us-west-2.amazonaws.com/d1082c5a-c804-4fd4-bc91-aa51bbe5d809/0e6c8989-a3c0-457b-bff9-dad2f95a476d/uo_cult.jpg)

World building

2024-07-28T00:00:00+02:00

3700

That one never-ending project every worldbuilder has

Micro-worldbuilding#

From time to time I like to draw or create something, while adding a small self-contained "lore" to it. These days I mostly do it as part of "Draw Together", a drawing event by Nyo_Archives.

For now, most of these are in french

Draw Together (Summer) : "Méduse aérienne (rouge)"

Draw Together : "Nymphe nocturne (jaune)"

La place des Tisserands est devenue à sa manière un lieu incontournable de Tralgnos. Au milieu de gratte-ciels vertigineux, une statue de Haltone perce une place sinon austère. Cette nymphe […]

Draw Together : "Gardien-ne fongique (vert)"

Si les symbioses sont communes dans la nature, les exemples sont plus rares pour les humains. Pourtant, les tribus Ghavra savent depuis longtemps tirer parti des Protelus Galvanisées, des champignons […]

Draw Together : "Vampire Aquatique"

Sous l'oeil sage d'Elben au zénith, les charbonniers sillonnent inlassablement la Mer d'Equi. Si ces voiliers défient déjà les dimensions habituelles des vaisseaux naviguant usuellement […]

Draw Together : "Pirate Fantomatique"

La flamme de l'humanité brûlait plus fort que jamais. Mais les services d'utilité publique peinaient à s'adapter. La mort (qui est un homme, peu de gens le savent), aussi connu sous le doux nom […]

Draw Together : "Arbre Cosmique"

INTERNATIONAL STORIES | alors que le décollage de la mission AAS-14 est imminent, la traditionnel commémoration de pré-vol s'est déroulée dans une ambiance solennelle. 32 ans après la tragédie du […]

Sysadmin

2024-04-15T00:00:00+02:00

Growing up in the french countryside, I was fascinated by the lightning far away on the mountains east and west. From time to time, thunderstorms would finally hit our valley, with a raging intensity.

The ambience of a hot, heavy summer evening, followed by a spectacular light show and finally fresh night grew on me.

Projects#

Hopefully, something will appear here if it succeeds. TBA

Thunderstorms

2022-06-24T00:00:00+02:00

The ambience of a hot, heavy summer evening, followed by a spectacular light show and finally fresh night grew on me.

The cells and me#

I started stealing the family compact camera to try to capture these elusive shapes: One night, standing on the edge of a field, surrounded by curious cows, I caught my first proper lightning strike:

graciously named "IMG_1331.jpg', shitty pixels in old file, 2012

After every summer family diner, I would jump on my bike to my favorite spot, unencumbered by hills and houses

As thunderstorms would sometimes get closer like curious cows…

Things started to get more…

… and more…

Involved.

Yes, it's stupid to be 1) this close to a thunderstorm 2) while near trees 3) and power lines 4) on a bike. It's all about managing risks and not being aware of them because you're an idiot.

As I moved to a large city with a lot of hills, thunderstorm chasing (and biking) got harder. But I'm trying to get something here and there.

Photography#

more >

Projects#

Hopefully, something will appear here if it succeeds. TBA

Bad mirror

2021-12-09T00:00:00+01:00

Your browser doesn't support HTML5 video tag.

This project uses a Raspberry Pi to turn a LED strip covered with paper boxes into a mirror using a webcam.

Source code available here in guirlande_cam.py

Content

More photos
Hardware
Wiring
Code

More photos#

Hardware#

The hardware used was rather typical for a project like this:

LED strips: five "WS281x" addressable LEDs, for a total of 250 LEDS. The strip we bought were advertised as "WS2811", but they have four cables rather than three, which suggest that they are WS2801 instead. The additional wire is apparently a backup data cable in case the LED burns. Information online is hard to come by due to the mixup by the provider (see "Wiring").
webcam: standard run of the mill webcam
power supply: typical 5V/25A LED Power Supply Unit, to accomodate for the 60mA * 250 = 15A at full power
paper boxes: traditional "water bomb" origami, 250 of them

Wiring#

As mentionned above, wiring turned out to be a bit difficult as the LEDs weren't properly labeled. But it turned out fine.

On the first LED strip, the blue (ground, GND) cable was plugged to one of the ground pins of the Raspberry Pi (#6, see the schematics, and the white wire to the GPIO18. Then, each strip received power from a "bus" cable, which is itself plugged into the power supply.

I'm used to work with both low power (such as electronic projects) and "high" power (such as house wiring), but here the mix of high intensity and low voltage weirded me out. But the small wires seemed to be enough, as it didn't not caught on fire nor released magic smoke even after several hours of continuous running.

Code#

The code was written in Python, using OpenCV (cv2) to get data from the webcam, process it (resizing and flipping) and show the intermediate result in a windows, and the rpi_ws281x library to drive the LED strips.

Thanks to the rpi_ws281x library, initialising the LED strip is pretty easy:

 1 # LED strip configuration:
 2 LED_COUNT      = 250 # Number of LED pixels.
 3 LED_PIN        = 18      # GPIO pin connected to the pixels (18 uses PWM!).
 4 #LED_PIN        = 10      # GPIO pin connected to the pixels (10 uses SPI /dev/spidev0.0).
 5 LED_FREQ_HZ    = 800000  # LED signal frequency in hertz (usually 800khz)
 6 LED_DMA        = 10      # DMA channel to use for generating signal (try 10)
 7 LED_BRIGHTNESS = 200 #255     # Set to 0 for darkest and 255 for brightest
 8 LED_INVERT     = False   # True to invert the signal (when using NPN transistor level shift)
 9 LED_CHANNEL    = 0       # set to '1' for GPIOs 13, 19, 41, 45 or 53
10 
11 REFRESH_RATE_MS = 10
12 
13 strip = Adafruit_NeoPixel(LED_COUNT, LED_PIN, LED_FREQ_HZ, LED_DMA, LED_INVERT, LED_BRIGHTNESS, LED_CHANNEL)
14 # Intialize the library (must be called once before other functions).
15 strip.begin()

Changing a LED colour is then done like this:

1 strip.setPixelColor(10, Color(255,0,0)
2 strip.show()

The RGB order didn't seemed to correspond between the webcam and the strip, so I hacked around a translator: as per commented, it might over complicated, but this is a hacky project and it worked:

 1 def cam_pixel_to_color(frame,x,y):
 2     """
 3     takes a cv2 frame, and return the pixel colour at (x,y) as Color
 4     while converting BGR (cam) to appropriate RGB
 5 
 6     While working RGB order might be convoluted, to fix
 7 
 8     """
 9 
10     try:
11         colour = Color(
12                     int(frame[y][x][1]), #B -> G
13                     int(frame[y][x][2]), #G -> R
14                     int(frame[y][x][0]) #R -> B
15                )
16 
17         return colour
18     except Exception as e:
19         print(f"[WARNING] Out of Bound on camera for ({x}, {y})")
20         return Color(0,0,0)
21 
22     return -1

Finally, as the strip was hung in "loops" on a support, I made some index shenanigans to unroll the image in reverse every other row:

1 def led_xy(x,y,color):
2     if (x % 2):
3         i = x * 25 + (25 - (y + 1))
4     else:
5         i = x * 25 + y
6     strip.setPixelColor(i, color)

Draconic space monorail (p5.js)

2021-10-15T17:44:00+02:00

About#

This map is procedurally generated (created using code) with p5*js. It generates a random population map, creates a set of public transport types and tries to link the mot populated areas and tries to link them using this network.

The source code can be found here

Aurorae experiment

2021-06-08T00:00:00+02:00

About#

I was trying to learn p5js, so I tried to create aurorae using particles with a procedurally generated snowy landscape.

Digital graffiti

2020-12-09T00:00:00+01:00

This project was intended as an upgrade of a project by davejavu1969, which allowed to use a wiimote as a virtual spraying can on a projected screen. We wanted to allow children of a computer-education-oriented association to paint on a wall during an event.

To do so, I upgraded the code to allow for multiple remotes (typically two, but more are possible), support different resolutions because we had various second hand video projectors (including one 1080p), and finally cleaned up the code related to calls to the cwiid library handling wiimote interactions, for easier developement.

The page for the original project (since disappeared) is available here
The code for the original project is (still) available here
My code is available here

The is a relatively old project I've made a while ago. The following instructions are a weird mix of technical and non-tech savvy instructions, for archival purposes.

Instructions#

Button Layout, in french:

Installation#

Preparing the Raspberry Pi#

Flash raspbian on a SD card, and then install the following packages to interact with the wiimote(s):

sudo apt install bluetooth python-cwiid

Testing#

Check that bluetooth and the remotes are working using the following command in a terminal:

hcitool scan

And by then pressing both + and - buttons on a remote. After a few seconds, the command should terminate and display the MAC address of the remote.

Non official remotes may not work

Write down the MAC address, and start over with the second wiimote if you have one.

Installing and preparing the project#

Clone the repo and modify the file digital_graffiti_multi.py by putting the MAC addresses from before between lines 570 and 574

Launching#

Before running it#

Plug in a mouse and keyboard, as well as a video projector (A screen can be used for testing) Then, plug in the power cable to start the Pi

Finally, plug the wii sensor bar.

Starting it#

Click on the raspberry in the top left corner, and go to "accessories" > "terminal"

Type the following commands to go to the right directory and launch the program:

cd digital_graffiti/
./digital_graffiti_multi.py

As the screen displays "connecting to can", press the + and - buttons on both remotes. One of them should have its first LED turned on, indicating that it got addressed as the first remote, and the other the second LED.

If the remotes stop blinking without leaving a LED turned on, press the buttons again to try the connection process again.

Launching again#

If the program crashes or if a child close it by mistake, simply press the up arrow key to bring the command back, and press enter to launch again.

Creating a desktop shortcut#

To simplify for non tech-savvy people, you can create a simple shortcut on the desktop.

Right click on the desktop and create an empty document called graffiti_numerique.desktop

Put the following content in the file, save it, and close it:

[Desktop Entry] Name=Graffiti numerique Comment=By EPN des Rancy Inc
Icon= Exec=xxxxx Type=Application Encoding=UTF-8 Terminal=false

Hologram

2018-10-13T00:00:00+02:00

Sommaire

Photos
Code

In 2018 I made a "hologram" using the typical clear-plastic inverted pyramid. The project went through several iterations.

Its goal wasn't to be ground-breaking but rather to entertain kids et even adults in events around digital and visual projects, like the "Expériences Numériques" (defunct website) and the Journées du logiciel Libre (https://jdll.org)

The first iteration was an activity meant for kids, where they would build a small pyramid, to be placed on a smartphone to create a basic hologram using pre-made videos on the internet.

The second iteration was an autonomous installation where people would (try to) follow instructions in a terminal to create a hologram of their face, kind of like a 3D photo booth (except faux-3D), on a fairly big pyramid. around 50 holograms were created.

The last one was a crossover with a light-painting workshop, where people (mostly kids) would make a light-painting photograph and see it display in "3D" on the hologram.

This is the few photos I've been able to find in my archives or using the Internet Archive (the association website being now defunct).

The (sub-par) code is at the bottom.

Photos#

Code#

(This script requires imagemagick, and might not even be compatible anymore, provided as is).

 1 #!/bin/bash
 2 
 3 echo "la capture durera 3 secondes !"
 4 echo "Entrez votre mail afin que l'on vous envoie le fichier à postériori:"
 5 
 6 read mail_addr
 7 
 8 echo "(Attention, si vous vous trompez vous devrez refaire la vidéo !)"
 9 
10 captime=$(date +"%Y_%m%d_%H-%M-%S")
11 
12 echo "$mail_addr: $captime" >> ~/liste_mail.txt
13 
14 echo "capture dans..."
15 echo "5..."
16 sleep 1
17 echo "4..."
18 sleep 1
19 echo "3..."
20 sleep 1
21 echo "2..."
22 sleep 1
23 echo "1..."
24 sleep 1
25 echo "capture !"
26 
27 streamer -q -c /dev/video0 -f rgb24 -r 25 -t 00:00:03 -o /home/jdll/holo_files/outfile.avi
28 
29 echo "#######################"
30 echo "fini !"
31 echo "#######################"
32 
33 echo "début du traitement : cela peut prendre jusqu'à une minute"
34 
35 convert /home/jdll/holo_files/outfile.avi -background Black -scale 50% -rotate -45 -extent 200x200 -delay 4 /home/jdll/holo_files/out0.gif
36 convert /home/jdll/holo_files/outfile.avi -background Black -scale 50% -rotate 45 -extent 200x200 -delay 4 /home/jdll/holo_files/out1.gif
37 convert /home/jdll/holo_files/outfile.avi -background Black -scale 50% -rotate 135 -extent 200x200 -delay 4 /home/jdll/holo_files/out2.gif
38 convert /home/jdll/holo_files/outfile.avi -background Black -scale 50% -rotate 225 -extent 200x200 -delay 4 /home/jdll/holo_files/out3.gif
39 
40 convert /home/jdll/holo_files/out0.gif -repage 400x200 -coalesce null: \( /home/jdll/holo_files/out1.gif -coalesce \) -geometry +200+0 -layers Composite /home/jdll/holo_files/out01.gif
41 
42 convert /home/jdll/holo_files/out3.gif -repage 400x200 -coalesce null: \( /home/jdll/holo_files/out2.gif -coalesce \) -geometry +200+0 -layers Composite /home/jdll/holo_files/out32.gif
43 
44 convert /home/jdll/holo_files/out01.gif -repage 400x400 -coalesce null: \( /home/jdll/holo_files/out32.gif -coalesce \) -geometry +0+200 -layers Composite /home/jdll/holo_files/videos/final_$captime.mp4
45 
46 
47 killall vlc
48 
49 timeout 9 vlc --repeat /home/jdll/holo_files/videos/final_$captime.mp4

a-d.s - projects

Digital art

Bad mirror (Pi + WS281x)

Digital graffiti (Pi + Wii)

Hologram

proc.gen

Stellar ticket

Draconic space monorail (p5.js)

Aurorae experiment (p5.js)

Stellar ticket

About#

Elben

History#

Physical effect on Earth#

Moon cycle#

Exploration#

Life#

Altitude numbering#

Planetary system

Structure#

Aper-Elvow binary#

Pora#

Uroti#

Elben#

asteroid belt#

Julvenel#

Kabor#

icy asteroid belt#

Aro#

Paro#

Tranulk#

Erfartris#

kuiper belt#

Astronomy

Origin and myths#

Organisation#

A word on Oplmek#

The fall#

Today status#

3700

Astronomy#

Astronomy

Planetary system

Elben's system#

Elben

Elben's life and exploration

Tales#

Draw Together (Summer) : "Méduse aérienne (rouge)"

Too much sky for a pilot

the Uô cult

Svar Cheese Agreement

Monos class vessels

Moved

Moved

too much sky for a pilot

Monos class vessel

The Svar cheese preservation Symposium agreement

the Uô cult

Origin and myths#

Organisation#

A word on Oplmek#

The fall#

World building

3700

That one never-ending project every worldbuilder has

Micro-worldbuilding#

Draw Together (Summer) : "Méduse aérienne (rouge)"

Draw Together : "Nymphe nocturne (jaune)"

Draw Together : "Gardien-ne fongique (vert)"

Draw Together : "Vampire Aquatique"

Draw Together : "Pirate Fantomatique"

Draw Together : "Arbre Cosmique"

Sysadmin

Projects#

Thunderstorms

The cells and me#

Photography#

Projects#

Bad mirror

More photos#