ILM was and is an absolute software engineering power house and they started with motion controlled cameras for star wars at the time all their in house software was c++. A lot of software which is still used today. Pixars Renderman, Photoshop, Maya... was initially engineered at ILM or Lucasarts which were subsidiaries of Lucasfilm.
Maya was an Alias|Wavefront product, which was a subsidiary of SGI. It came along way after Pixar had been spun out of ILM. John Knoll, who co-developed Photoshop with his brother Thomas, is still at ILM as the CCO.