
Battle Bird – 1987 Developer Interview
Battle Bird was a stereoscopic 3D arcade game with a proprietary cabinet, developed by Irem with assistance from their sister/parent company Nanao. Its exact history is quite hazy, as it appears very few cabinets were produced, but this short interview helps shed some light. It doesn’t answer the mystery of “what happened?” (and even Japanese sites and messageboards are mostly in the dark), but it does make for a fascinating look at what could have been.
Our company, Irem, is a part of the Nanao Group of companies. This has the merit of giving us access to a nationwide management network, and, of course, hardware production facilities. Three companies in the Nanao Group are involved in game planning and development: Tamtex, Irem, and Nanao (the arcade division).
Tamtex is located in Tokyo, which gives us access to a lot of good business connections and keeps us updated on the latest news. They’re mainly involved in Famicom development. Irem (our company) is located in Osaka. We’ve handled the development of all our previous arcade games, and we have a great deal of knowhow there. As for Nanao itself, they have both a hardware and software department, and they played an extremely vital role in the development of Battle Bird.
The Nanao Group, therefore, brings together all three of these companies’ strengths, and allows us to develop software that no other single developer could. Right now in Japan, there’s a big problem with bootleg copies of arcade games and copyright infringement; however, because we don’t develop our software independently, but instead combine it with unique hardware, we can include copy protection at both levels (hardware and software).
In 1985, the arcade industry was starting to show some stagnation. Every company in the Nanao Group started searching for new plans to invigorate the market, and one of our ideas came from thinking about the new advancements in 3D technology. The development of Battle Bird began like that, by investigating the hardware side.
There’s no way to imagine how the final game might look without making a number of prototypes, so we needed hardware facilities that would allow for those many experiments. The development, therefore, was centered around Nanao and their facilities, where we would be able build up the hardware and software side-by-side.

Once we had a prototype completed to a certain level, we started thinking about how the actual game would look and play, and it was at this point that our developers from Irem joined the team.
We spent a great deal of time trying to find a gameplay system which would take full advantage of what the 3D hardware had to offer. From our first small experiments, to the final version, the development took us two years total.
The first thing we decided was to make a STG game set in outer space. We considered making a true 3D game, where you’d have total freedom of movement, but that would have made the controls too complex. In that case, shooting enemies down would have been nearly impossible without very exact, precise movement. Instead, we decided to fix one of those coordinates, to help the player determine the location of his ship. We also researched whether or not we should show the player ship on-screen in a third-person view, and ultimately we decided to do this, to make it easier for the player to tell how close he was to the enemies. If we had gone for a first-person view, then it would be much harder to dodge attacks: you might think you dodged something, only to have it hit the side or corner of your ship and die. That kind of situation would be very unsatisfying to players.
In Battle Bird, we’ve also spent a lot of attention on details that are not directly related to the gameplay. For example, with the cabinet frame, we researched what would be the best ergonomic position for people to sit in and peer through the viewer for extended periods. We also researched the average difference between a person’s individual eyes. The way stereoscopic 3D conveys depth puts a certain amount of stress on the eyes, and it’s related to the distance between them. We also considered the problem of flashes of light in a dark space. The Battle Bird cabinet contains two monitors, and their image is joined together using a half-mirror.

Since you’re flying around in a 3D space, it necessitated creating over 1000 different graphic patterns of the player ship, in order to show it from all the different angles. We didn’t draw them one-by-one, of course; we used a computer graphics program to assist us.
We also exhibited Battle Bird at a recent Computer Graphics Expo Show. We were the only arcade game on display there, so the people who visited us were both surprised and pleased to see us there. Irrespective of its “video game” genre, the 3D in Battle Bird is state of the art, and we got various invitations and requests: one person wanted to use the cabinet and its blueprints as a reference in educational materials.
Developing a 3D system in a video game presents various distinct challenges. First, there’s the problem of 3D glasses: they present a physical wall, and make it harder to simply enjoy the game. Then there’s the large cabinet—larger than other arcade games, which means it takes up more space on an arcade operator’s floor. And a 3D game like Battle Bird can’t be watched by onlookers, which is another issue. Even at Irem, we’re still a long ways off from solving these fundamental problems.
Previously, Irem has invested a lot of our energy and research in traditional animation technology. Other game developers see sprites as a mere means to an end, a symbol that you just move around on-screen; at Irem, however, we focus a lot on what we want the player to see—that is, graphics and visual presentation. However, because computers have limited memory, we can’t always focus on every detail to the extent we’d like. We instead have to grasp the essentials, the most important parts—and then focus our efforts there and make those things as beautiful as possible. You can see that dedication in the sprites for our new game, R-Type: the huge battleship in stage 3, the erotic-yet-grotesque enemy designs, the wave cannon… our goal at Irem is to impress you!


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