CHARLESTON, S.C. — Four years ago, Hunter Heidenreich was interested in computer programming and art, so he started writing code that used algebra and trigonometry to draw patterns.

Basic algorithms, he realized, could produce interesting designs, colorful combinations of arcs and asymptotes — curving graph lines — you might expect from a graphing calculator gone haywire.

But Heidenreich shelved the files. A freshman in high school, he didn’t have much use for them.

Four years later, he’s found one. The Charleston 18-year-old and three friends started to make T-shirts and socks with the designs under the moniker ByteCode Designs, pitching their wares as “fashion for the digital native.”

“People who have grown up with technology in the palm of their hand. People who see these pixel patterns, and they’re like, ‘Whoa. I don’t know what’s going on, but I like that,'” Heidenreich said.

To be sure, the patterns of ByteCode’s shirts aren’t as complex. The concept behind them is fairly simple, Heidenreich said: Give each pixel a set of numbers, run them through a few formulas and pair the numbers they produce with colors.

The results, though, are somewhat unexpected, with patterns that look like glitched-out computer screens and color schemes that belong in a dance club.

“When you start implementing trigonometry, that’s when things can get really crazy,” Heidenreich said. “Let’s say you have the equation for a circle. You would think if you put it in this program, it would draw a circle, but it doesn’t. It loops through the colors in a circular pattern, so it ends up creating not a circle. It’s kind of mind-blowing.”

“None of us understand the process,” added Mackenzie Pelletier, 17, of Charleston, who’s helping market the shirts.

And in a way, that’s the point.

The idea is to make programming fashionable, said Zachary Speaks, 18, of Charleston — to create something cool out of a concept like computer code, something that shapes much of modern life, even if it’s not widely understood outside the tech community.

In a way, it’s a play on computers and smartphones themselves — that they’re enormously complicated but still have an immediate appeal. Users don’t have to know how software works to know they like it.

The quartet, which is rounded out by Noah Evans, 18, of Charleston, hasn’t sold many shirts yet, about 15 so far. But as they head off to college this fall they’re hoping that their spreading networks will gin up business at their new schools, from Georgia to Pennsylvania.

They hope their marketing efforts will help, too. On top of traditional efforts of pitching strangers on Twitter and in Marion Square, they’ve structured ByteCode’s website as a video game of sorts.

Tag the company in a tweet, and the store gains an experience point. Leave a review and it gets five. Buy a shirt and it goes up 20. As the site gains points, more products and patterns come out.

That’s the point, too, Speaks said, to reference a concept immediately familiar to digital natives who grew up playing video games.

“It’s who we want to be as a company and a clothing brand,” Speaks said. “Part of that is an homage to our childhood.”

Information from: The Post and Courier,