London-based Solid State Group decided to combine Slack with a giant LED wall, and created a thing of beauty for their office.

“BUILD THE WALL we cried aloud. Well, in truth, we shouted this over Slack, until the pixel wall became a thing.” Niall Quinn, Solid State Group.

Flexing the brain

Project name RIO: Rendered-Input-Output took its inspiration from Google Creative Lab’s anypixel.js project. An open source software and hardware library, anypixel.js boasts the ability to ‘create big, unusual, interactive displays out of all kinds of things’ such as arcade buttons and balloons.

Every tech company has side projects and Solid State is no different. It keeps devs motivated and flexes the bits of the brain sometimes not quite reached by day-to-day coding. Sometimes these side projects become products, sometimes we crack open a beer and ask “what the hell were we thinking”, but always we learn something – about the process, and perhaps ourselves.

Niall Quinn, Solid State Group

To ‘flex the bits of the brain’, the team created their own in-house resource. Utilising Slack as their interface, they were able to direct images, GIFs and video over the internet to the Pi-powered LED wall.

Bricks and mortar

They developed an API for ‘drawing’ each pixel of the content sent to the wall, and converting them to match the pixels of the display.

After experimenting with the code on a small 6×5 pixel replica, the final LED wall was built using WS2812B RGB strips. With 2040 LEDs in total to control, higher RAM and power requirements called for the team to replace their microcontroller. Enter the Raspberry Pi.

“With more pixels come more problems. LEDs gobble up RAM and draw a lot of power, so we switched from an Arduino to a Raspberry Pi, and got ourselves a pretty hefty power supply.”

Alongside the Slack-to-wall image sharing, Solid State also developed their own mobile app. This app used the HTML5 canvas element to draw data for the wall. The app enabled gaming via a SNES-style controller, a live drawing application, a messaging function and live preview capabilities.

Build your own LED wall

If you’re planning on building your own LED wall, whether for an event, a classroom, an office or a living room, the Solid State team have shared the entire project via their GitHub page. To read a full breakdown of the build, make sure you visit their blog. And if you do build your own, or have done already, make sure to share it in the comments below.