This week sees the western launch of 3D Streets of Rage 2, the latest in Sega's line of 3DS-based 3D Classics. It's one of the most beloved games of the 16-bit era, and also one of the most technically impressive Genesis / Mega Drive titles seen so far. In fact, the game is such a potent showcase of the console's abilities that developer M2 initially told Sega that it would be impossible to port to the 3DS with 3D effects and local multiplayer enabled.

Yosuke Okunari, producer at Sega, and Naoki Horii, president at M2, have taken part in an interview where they talk about the process of bringing the famous brawler to Nintendo's handheld:

YO: For Streets of Rage, we thought that since we are limited to only five games, we should skip the first one and go straight to the sequel. I proposed the idea of starting with the sequel to M2. I was immediately turned down. (laughs)

NH: I told him, "It's impossible!"

YO: He said it wouldn't work because the Mega Drive requires too much processing power.

NH: That's right. It takes a lot of resources to emulate the Mega Drive, and adding stereoscopic 3D requires even more on top of that.

In fact, M2 found porting the original Streets of Rage - a much less demanding title from a technical standpoint - to be quite a challenge:

YO: And then there's Streets of Rage, which was Batch 1's final title, meaning that it was an incredibly hard game to develop. Sonic the Hedgehog, Altered Beast, Ecco the Dolphin, and Shinobi III were all pure horizontal side-scrollers. So we wanted to have a beat'em up, and Streets of Rage is visually perfect for a stereoscopic 3D treatment. The end product really makes you go "Now THIS is 3D!", but at the time, M2 wouldn't go for it.

NH: We just didn't know if we could pull it off.

YO: It's a linear game, so I tricked him by saying, "All you need to do is add depth to the beginning of Stage 1, and then it's just copy and pasting from there!"

NH: "As if it's going to be that easy," I thought. But we got it done, thanks to our experience with the previous seven games.

Streets of Rage 2 features more complex scrolling - including stages with diagonal movement - and also runs at a faster frame rate, all of which made the project a bigger task than the original:

NH: When considering the original Streets of Rage, we knew doing a 3D conversion was going to be hard, but since the game used small sprites and ran at 30 frames per second (fps), we figured it was at least possible. We were having a hard time maintaining the Mega Drive running at full speed on the 3DS at the time. This game seemed like it would be easy on processor, so we gave it a try, despite my doubts of it being a copy-and-paste job. (all laugh)

YO: There were spots where we had to manually convert parts to 3D where we couldn't copy-and-paste, like the elevator on Stage 7, but in the end, the floors in these beat'em ups just look great in 3D. Also, we wanted to be sure to have Local Play, so we put in multiplayer the same way we did with the Game Gear Virtual Console games. But there was a problem with implementing Local Play for Streets of Rage 2: it runs at 60 fps.

NH: The characters are huge, and the wireless play runs at 60 fps? Streets of Rage ran at 30 fps, so we figured it wouldn't be too hard to keep up with at 30. But Streets of Rage 2 was tightly made. I mean they squeezed every bit of juice out of the Mega Drive on that one. It just oozes with the spirit of "Let's put everything we can in," so we knew that bringing it to the 3DS would be a real challenge.

In fact, the project might have stalled entirely were it not for the efforts of one of M2's talented programmers, who went beyond the call of duty to make things work:

NH: Converting Streets of Rage into 3D as a huge undertaking, and the programmer in charge of the stereoscopic 3D work was at it nonstop for a month or two. When the project was over, he said, "I've worked 48 hours every day. I deserve a vacation. Basically, I'm going to drop off the radar for two weeks."

He first working on the 3D conversion of Sonic The Hedgehog, all while giving Streets of Rage a lot of thought as to how he was going to do it. With Sonic The Hedgehog setting the bar, it really put the pressure on everyone to deliver. He was very influential on the quality level we strive for in the Giga Drive 3D conversions. After those two weeks of rest, he came back, and as if turning in his homework over summer vacation, he handed over this program he'd been working on over his break. It was the entire first stage of Streets of Rage 2 in 3D. Putting aside the fact he didn't actually take a break (all laugh), he had gone and made this. It was running on the PC, and while we weren't sure we could squeeze down the processing to fit, not only did the diagonally scrolling bits work, it looked really cool.

YO: Everyone was shocked. I mean, the games for the second batch had already been chosen and locked in. He must've have believed we were going to do more.

NH: Who knows? I'm thinking that he did it because people said it couldn't be done. He's that kind of guy.

YO: So then back in the fall of that year, Horii-san stops by and hands me some 3D glasses and says, "Hey, check this out." And there it is. Streets of Rage 2 working in a development environment. (all laugh) He's like, "Hey, check out this diagonal action!" (laughs) "Horii-san, you said it couldn't be done, but here it is!"

NH: I wanted him to see it because we'd done it, but I didn't think he'd give me such a hard time about it. (all laugh)

3D Streets of Rage 2 launches this week on the 3DS eShop. Be sure to check out our initial impressions here.

[via blogs.sega.com]