The Institut du Monde Arabe (IMA) is one of the most elegant and instantly recognizable buildings in Paris. A museum, art gallery and also a powerful architectural symbol of peace and cultural exchange. It has graced the Seine’s left bank since 1987.

Design-wise, the IMA is famous for its iconic southern façade, created by the architect Jean Nouvel. It is covered by a mosaic of 240 mashrabiyas — ornate, latticed window protectors that are a common sight in the Middle East, where they are used to shield buildings from the full glare of the sun.

To celebrate the IMA’s 30th anniversary, its president, Jack Lang, asked High Scream to conceive a permanent light display for the façade. Something that would make it a landmark at night as it is during the day. What we came up with had never been seen before: we integrated LED lights into the mashrabiyas themselves, turning the whole façade into a giant, programmable electronic artwork — a modern, bold and beautiful new addition to the Parisian skyline after dark.

The large crowd gathered in the plaza outside the IMA, knew there would be a show — but nobody knew exactly what to expect. A substantial DJ booth in the centre of the plaza confirmed that there would be music. Sure enough, at 9pm, when daylight had given way to darkness, ambient electronic textures began to fill the air. Then, to delighted gasps, the building itself flickered into life.

Square blocks of light began to dance around its façade, as if it had been take over by an artificial intelligence. The patterns evolved in time with the music. Squares congregated to form larger blocks that swept upwards from the ground. Narrow beams fizzed across the surface like comet trails. Warm yellow rays began to radiate from the centre, like sunbeams, before giving way to a grid-like maze of pulsating sparks. And then, after exactly three minutes, two giant digits appeared: a three and a zero. Happy thirtieth birthday, IMA.

As the party on September 29, 2017, continued, and DJs took to the turntables, the light display rolled on, in perfect synchronicity with the sounds. The traffic on Boulevard Saint Germain slowed to a crawl as drivers stopped to stare. The IMA looked as if it had been beamed down from another world.

In the run-up to the party, the building’s southern facade was fitted with LED lights. The façade comprises of 240 square mashrabiyas — ornate window protectors, common in Middle Eastern design. Into each square we placed 12 LED strips, carefully arranged around each edge, creating a grid of 2,880 strips in total.

The strips are capable of emitting two varieties of white light — warm, with shades of yellow, or cold, with shades of blue - to compliment the mashrabiyas’ function, to regulate the building’s temperature. Each strip can be individually programmed, giving 5,760 possibilities of light sequences — blocks, lines, geometric symbols, numerals, letters…

The strips are programmed on a computer using pixel maps, which were created in advance by High Scream’s technical operations director, Bertrand Desaintpern.

To make the maps, Bertrand used bespoke software to build a template of the IMA’s façade, with all the LED strips in their exact position and to scale. This template enables its user to separately program each LED strip, to build patterns — pixel maps — that can be sequenced like animation frames, before being connected to the IMA’s lighting system to activate the facade. A simple way to think of the pixel map is as a platform that marries the technical and creative parts of the visual display.

Now, the lighting choreography could begin. This was all directed by founder and creative director Romain Pissenem. Jamie Franks and VJ Steve Page spent weeks programming the pixel maps with scores of light sequences. They then controlled the visual display in real time at the launch party along with light designer Ian Tomlinson. These sequences could be anything from one-off displays triggered by striking a computer key, to loops that can be layered together in infinite combinations, to “generative” displays that evolve of their own accord, which can run indefinitely — all moving in time to the bpm of the music.

“The beautiful thing about this project was the limitation of the canvas we had to work with,” says Jamie. “It’s essentially light and squares, so that forces you to think differently about how motion evolves across a surface. We experimented with sweeping light across the building, “snakes” that slither across the thin light channels, or boxes that can be clustered as chunks of light. We drew influence from everything from old-school games like Tetris through to Arabic graphics and geometric patterns.”

They curated a three-minute opening sequence, accompanied by a dramatic Jean Michel Jarre-like soundtrack, to launch the party. After that, as the DJs took control of the music. Meanwhile the light display was in the hands of VJ Steve Page, working from a desk at the back of the plaza, surrounded by computer screens, electronic pads and keyboards. As the music peaked, troughed and swirled, Steve triggered, mixed and adapted the light sequences to match the mood, to create a unique live visual display. “It’s partly seeing and partly feeling,” is how Steve explains the performance aspect of his job. “You become completely immersed.”

Now, the IMA’s new visual architecture is a bold new landmark on the Parisian after-dark skyline. A five-minute display, comprised of edited highlights from the inaugural show, illuminates the building every hour at night. “It will be lighting up the Paris sky for a long time to come,” says Jamie. “It has been our first time working with a piece of iconic architecture, embellishing and, hopefully, improving it. It has been a privilege to be involved.”