Teiji Yutaka, a contributor to the development of the original PlayStation, has been deeply involved in the gaming sector for years. Recently, he has been at the forefront of research on cutting-edge technology for interactive entertainment. Sony Group’s technology blog recently sat down with him to discuss his career, passion for technology and recent work. Read some excerpts below from the interview. 

Note: Interview condensed for brevity. To read the full interview, go to Part 1 here and Part 2 here. 

What are some of the interesting technical challenges you encountered during the early days of PlayStation?

When it came to the concept of PlayStation, Ken Kutaragi, the project leader, had a clear vision in his mind. At that time, films entirely created with computer graphics (CG) were just beginning to emerge, and he wanted to bring that fully CG world into gaming.

However, achieving a fully CG-based game presented immense challenges. Initially, I thought that by pre-rendering video backgrounds in CG and placing characters in front, we could create the impression of an interactive, moving background. This approach did indeed produce a fully CG game, but it felt too simplistic. From the player’s perspective, it was almost like you could defeat enemies by just shooting. It made me question whether such a game would truly be engaging.

This led to a change in thinking: we decided to create everything on the screen in real-time CG. For smoother motion, real-time CG requires at least 30 frames per second, meaning each frame must be generated in 1/30 of a second. The smallest unit in a 3D world is a “polygon,” which consists of three vertices, and combining many polygons allows for creating detailed objects. The question then was, how many polygons and computations would be needed? Taking the first demo we created for PlayStation as an example, the dinosaur model was made up of 2,700 polygons. To project a moving dinosaur onto the screen, we needed 243,000 vertex calculations per second (2,700 polygons × 3 vertices × 30 frames).

The First Demo Dinosaur Created for PlayStation

At the time, workstations capable of such processing power cost tens of millions of yen, so recreating this on a home console was a major challenge. Mr. Kutaragi’s idea was to embed the vertex calculation capabilities into a semiconductor chip within the CPU, making mass production affordable. This led to the development and integration of the geometry engine1, which became the key breakthrough and one of the foundational technologies for the PlayStation series.

While I was directly involved in development up until PlayStation 3, my focus as a software engineer was to provide a user-friendly development environment for game developers. I managed the 3D graphics library, delivering the 3D software library as an API for developers.

The techniques and principles I honed here eventually paved the way for my current specialization in interactive technologies like real-time ray tracing. Currently, I leverage my experience to shape the vision and direction of Sony’s digital interactive technologies. My current interest lies in examining the game industry from the perspective of real-time 3D graphics and understanding how new technologies will transform gaming.

What would you say is Sony’s key strength in the gaming field?

In gaming, real-time capability is essential; it forms the basis of everything we create. A major strength of Sony is the ability to apply technology originally developed for gaming to other fields. For example, in virtual production, the camera must be synchronized with the displayed background in real time, which directly leverages real-time CG technology horned in gaming. Applying realistic effects like real-time ray tracing to other industries can lead to even greater advancements.

Another promising area is the combination of simulation and AI. Simulation relies on computational power to derive answers through deduction, while AI uses induction, applying knowledge and data from the past to predict outcomes. By combining these approaches, we can take a new path: progressing calculations partially and using AI’s inductive reasoning to reach final conclusions. This hybrid approach expands possibilities beyond conventional methods.

The previously mentioned PlayStation 5 Pro’s PlayStation Spectral Super Resolution (PSSR) is a prime example of this approach. For instance, it can render in 2K resolution and then upscale it seamlessly to 4K with high sharpness using AI. Beyond just PSSR, I believe Sony’s team of Distinguished Engineers, each excelling in their respective fields, will continue to leverage their strengths and collaborate effectively to enhance Sony’s unique capabilities.

How do these technological advancements ultimately benefit game users?

This may sound like a wild idea, but one concept is that through AI, content could become more customized to individuals.

Currently, everyone experiences the same content, but in the future, content might adapt dynamically to each person’s preferences and skill level. Thanks to AI, it could evolve in real time. This approach is particularly promising for games, where players’ proficiency levels are more evident. For instance, the game could subtly adjust the difficulty to keep them engaged, enhancing the experience and reducing the likelihood of disengagement.

PlayStation celebrates its 30th anniversary this December. Could you share your thoughts on this milestone?

It’s been 30 years since we launched the original PlayStation in 1994. To this day, PlayStation continues to receive support from countless users, and its technology has kept evolving. I believe this longevity is largely thanks to the clear direction set from the start. By establishing high hurdles like “real-time” and “3D graphics” from the very beginning, we laid a foundation that encouraged combining various technologies. These advances have evolved in line with increasing computational power, and I am deeply grateful to have been a part of such a remarkable product.

  1. Geometry Engine: Software or hardware specialized in coordinate transformation in 3D graphics ↩︎