* The development of the OpenGL graphics API: Lengyel was one of the original developers of OpenGL, a cross-platform graphics library widely used in computer graphics applications.
* The creation of the book "OpenGL Programming Guide": This book, also known as the "Red Book," is considered a seminal work in OpenGL and has served as a foundational resource for generations of computer graphics programmers.
* Research in computer graphics algorithms: Lengyel has published extensively on various topics in computer graphics, including rendering, animation, and geometric modeling.
His most notable works include:
* OpenGL Programming Guide (The Red Book) (with Dave Shreiner, Mason Woo, and Jackie Neider): A comprehensive guide to using the OpenGL graphics library.
* OpenGL ES Programming Guide (The Orange Book) (with Dave Shreiner and Graham Sellers): A guide to using OpenGL for mobile and embedded devices.
* Mathematics for 3D Game Programming and Computer Graphics: A book exploring mathematical concepts essential for computer graphics and game development.
* Foundations of Game Engine Development: A text covering the fundamentals of game engine design and development.
While Lengyel is primarily known for his contributions to computer graphics, he has also authored articles and books on other topics related to computer science and engineering.