Before Ken Wesley ever made a digital tornado twist or a computer-generated hovercraft blow back trees, he liked to sit and watch the rain fall at home.

Wesley, 55, now an instructor at LSU, worked for three decades in the early days of computer generated imagery — CGI — creating scenes for “Mission Impossible,” “Harry Potter and the Sorcerer’s Stone,” and several other blockbusters.

His childhood in rural Foxworth in south Mississippi created a foundation for his work.

“I had a lot of time to watch rain fall or watch grass blow in the wind or natural phenomena — leaves falling from trees,” he said. “Those are the things that, as a visual effects artist, I became known for, recreating natural phenomena in the computer. That’s what I love.”

In January, Wesley became an instructor in LSU’s Digital Media Arts and Engineering program, which teaches master’s level students to create digital 3-D images for films and video games. They learn what Wesley taught himself to do, translate the natural world into a computerized language.

Since the 1980s, Wesley has helped develop much of the animation that his students have grown up watching.

“Ken brings decades of experience from the very early days of CGI to a group of students who grew up with it and take it for granted,” said Marc Aubanel, director of the program.

Wesley became interested in art at an early age, taking painting lessons as a 12-year-old after school. As a teenager, he knew he would attend the University of Southern Mississippi in nearby Hattiesburg, but he didn’t have plans for a career.

One night before his high school graduation in 1977, Wesley was leaving his parents’ house when he saw a few minutes of a “60 Minutes” segment on a new medium — computer animation — that featured a program at a university in New York.

“I looked at the TV as I was opening the back door,” he recalled, “and I said, ‘That is what I want to do.’”

He majored in computer science and minored in math. As a senior, he sent out just one resume — to the New York Institute of Technology’s computer animation laboratory, the program he saw on television years before.

Unexpectedly, they hired him.

Wesley started working on some of the early 3-D computer animation sequences, television commercials and title sequences for CBS Sports programs.

“It was new then. It was cool then,” Wesley said. “It’s expected now.”

Eager to work on bigger projects, Wesley moved to Germany before being hired at Industrial Light and Magic, the visual effects company founded by George Lucas.

In the mid-1990s, major films began to use computerized visual effects regularly. Wesley worked on one of the best-known segments of “Mission Impossible,” a fight atop a high-speed train, and an effect in “Harry Potter and the Sorcerer’s Stone” where a villain turns to ash.

Wesley’s work is equal parts art and mathematics. Starting with an image, he can create a computer program that creates an entire world.

One leaf of grass can become a field, each blade unique in the way it twists in the wind or curls toward the sun.

“One of the things I still like doing is studying some natural phenomenon or some process and then trying to figure out the mathematics that are at play,” Wesley said.

After nearly a decade at Industrial Light and Magic, Wesley left computer animation and California. He moved to Bay St. Louis, Mississippi, to paint.

Long hours at a computer had begun to alter his mind, he said.

“I am in the virtual world inside the computer doing stuff,” he said. “I am operating in a space that really exists inside my head, but it seems to be inside that monitor.”

He often longed for the rain, the grass, the nature with which he had grown up.

“I struggle with balancing that artificial technological influence on my life with the thing that makes grass grow,” he said. “It’s a huge struggle.”

When Hurricane Katrina struck the Gulf Coast in 2005, Wesley lost everything at his home in Bay St. Louis. Since then he has moved between California and Mississippi, alternately painting and working on movies.

CGI experts are no longer hired longterm, he said, instead working on a less-secure contract basis.

Last summer, Wesley finished work on “The Hunger Games: Mockingjay Part 1” and was hired to teach at LSU.

The new job offers security and the opportunity to work in the future of computer graphics. Wesley said he believes that films as we know them will die out. In the future, viewers will desire more interaction, like a video game.

“Every single person is going to have a different experience with that product,” he said. “I want to do that. I want to be involved in that.”

Teaching the next generation of visual effects artists, he has his chance.