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John Romero explains how a Super Mario Bros. 3 PC clone changed games forever

microsoft apology for sexist gdc entertainment john romero
John Romero GDC/Flickr
An apocryphal text of video game history was unleashed upon the Internet recently, as legendary game designer John Romero shared footage of an unreleased PC port of Super Mario Bros. 3.

It’s easy to look at the clip and wonder what could have been, should Nintendo have taken up Romero and his colleagues on an offer they made at the time. If Japanese console development and the nascent American PC gaming scene had crossed paths at that crucial moment, the industry would look very different today.

Instead, the project was repurposed, a development process that would have lasting effects on the way video games are made. Last week may have been the first many of us saw of the Super Mario Bros. 3 prototype, but the winding path of its development has long since snowballed into common practice, Romero told Digital Trends.

Smooth Scrolling

Today, John Romero and John Carmack are renowned throughout the video game industry. Back in 1990, however, they were just passionate people with talent — and the need to make a bit of cash to pay the bills.

David Kushner describes the first meeting between the two as follows, in his seminal book Masters of Doom: How Two Guys Created an Empire and Transformed Pop Culture:

Carmack was unprepared to meet anyone who could keep up with him intellectually, particularly in programming … Romero was inspiring, not only in his knowledge of programming but in his all-around skills: his artistry, his design. Carmack was cocky, but if someone could teach him, he wasn’t going to let his ego get in the way. On the contrary, he was going to listen and stick around.

Both Romero and Carmack took jobs at a video game developer called Softdisk. Their technical abilities set them apart from the crowd, as back in these early days of the industry, it was impossible to make a game work without the talents of a programming wizard who could turn ideas into code.

Console gaming was dominant, and Nintendo sat at the head of a table. In the era of 2D gaming, side-scrolling action was the equivalent to the modern day FPS — but the technology to make levels scroll as a player traveled through them had not been mastered on the home computer, despite efforts to do so.

“I was working late one night with Carmack,” Tom Hall, another Softdisk employee who would go on to co-found id Software, told Digital Trends. “He’d just used a video card buffer trick to let the card do the work of scrolling, rather than moving the data byte by byte or word by word in code.” Hall notes that this was the first time smooth scrolling had been accomplished on a PC.

“Up till now, scrolling was either SLOW or chunky. So this was kind of a big deal.”

Power Graphics ProgrammingToday, someone with minimal programming knowledge could have a 2D side-scroller up and running in minutes thanks to tools like Unity and Game Maker. It’s trivially easy to find a tutorial on how to program a particular mechanic, or even find code that can be freely dropped into your own project. But back in 1990, the designers working at Softdisk had almost no prior work to refer to. Almost everything had to be coded from scratch.

“We had a book called Power Graphics Programming,” said Romero, crediting the textbook for help with smooth scrolling and EGA mode. “Back then, especially on PC, there was no hardware support to do anything. Other hardware had sprite systems, but the PC didn’t have anything like that. It was a real hassle putting pixels on the screen.”

Smooth scrolling was an important breakthrough — the next question was what to do with the technique. “I looked over at the NES in corner, which had Super Mario Bros. 3 on it,” Hall told me. ” I had an idea, and turned to Carmack. ‘What if we made the first level of Super Mario Bros. 3 … TONIGHT?’  Carmack smiled, and said, ‘Okay, let’s do it!'”

Super Mario Maker

Carmack set about coding, while Hall focused on creating some graphics. A player character had already been implemented — a creation of Romero’s known as “Dangerous Dave.” The next step was to painstakingly proceed through the level, pausing at regular increments so Hall could replicate the visuals on his computer. Finally, these graphics were laid out in TED, a tile editor put together by Romero.

“By 3:30am, we had the little guy jumping around the level. Then I made a title screen, calling it ‘Dangerous Dave in Copyright Infringement,’ because Nintendo would sue us for making a Mario copy. We put the joke game on a disk, dropped it on Romero’s desk, laughing and tired, and went home to crash.”

Dangerous Dave in Copyright Infringement
Image used with permission by copyright holder

The game was a hit with its one-man audience. “The next day, we got in late, and went into the office, and Romero pulled us in a room and shut the door,” Hall relates. “I’ve been playing this all day,” Romero said. “We’re so out of here.”

“The millisecond I saw it, I knew everything had changed,” Romero told me. “I was looking at something no one had seen on the PC at that time.” Discussion soon turned towards what could be done with the technology. “Since we replicated the graphics and the scrolling, why don’t we do a port?”

No one involved with the project felt any real reason to take it to their superiors at the company, however. “Softdisk didn’t want to do a game like it,” Hall remembers, “because it didn’t work in CGA, the four color mode. It was a trick only doable with an EGA card.” There was another option, albeit one that took a more unusual route. “Since they didn’t want to do it, we thought we might try to see if Nintendo did.”

It was something of an outlandish idea — win the favor of the console kings by demonstrating your ability to replicate their game on PC hardware. That said, Nintendo would have a great deal to gain by cornering the burgeoning PC video game market.

“Up till then, scrolling was either slow or chunky. So it was kind of a big deal.”

“Jay Wilbur knew someone at Nintendo, so we got in touch, and they said send us a demo,” said Hall. The team went into crunch mode, eager to build something worth showing to the company. Tom was now working from footage recorded on a four-head VCR rather than a paused version of the game, according to Romero. “Two-head made it look blurry, and he needed to see pixels.”

Ultimately, Nintendo would decide not to pursue the PC market, although Romero told me with pride that the prototype was delivered to Kyoto to be considered in person by senior management. The project would have a huge influence on the future of the company, and indeed the video game industry as a whole.

From copycat to trendsetter

“It’s totally different,” Romero replies when I ask about the challenges of recreating an existing game on new hardware, compared to creating something original. “It’s a lot easier than normal. When you’re creating a new game, it’s completely blue sky. You have no idea what needs to be done, so you just start inventing it.”

Nintendo didn’t want to commit, but the groundwork was too good to go unused. “We need to make another game with this tech,” Romero decided. The idea for an original spin on the 2D platformer started to take shape.

commander keen cropped
Image used with permission by copyright holder

“We thought, why not do it ourselves?” Hall told me. “Romero had been contacted by Apogee. So I said to the guys, ‘I can come up with anything — what kind of game do you want to make?’ Carmack said, ‘A kid that saves the galaxy or something.'” Tom spent 15 minutes working in isolation, and came back with the basic concept for Commander Keen.

Commander Keen, when it came out, was as massive as Doom was when it came out,” said Romero. “It was huge.” The game produced several sequels and has now reached cult status, but the fact that it was forged from the remnants of the failed Super Mario Bros. project might be the most remarkable aspect of its development.

Back in those days, no one carried their code forward.

“Back in those days — especially in the 80s — no one carried their code forward,” Romero continued. “We always started completely from scratch.” Work done on the Super Mario Bros. 3 port helped with the development of Commander Keen, as well as titles like Rescue Rover. Years later, the same concept would help id Software change the face of PC gaming with Doom and Quake, both of which were built on engines that spanned multiple games, and were licensed to other companies for their own titles.

“I didn’t work from any claim made by id Software, Romero, or Carmack,” explained Henry Lowood, Curator for History of Science & Technology at Stanford University. “I began simply by asking when the term was first used.” Lowood is referring to the term “game engine,” which he asserts was coined by Romero.

Getting the first game engine running

It takes a lot of time and effort to build the framework any video game runs on. Today, developers will often implement a game engine created by another studio to try and cut down on costs and time. The work of id Software in the 1990s popularized this strategy.

“The earliest use I could find was described in interviews with John Romero, in which he cited use of the ‘Keen Engine’ as a term in 1991,” Lowood told me. “During the summer of that year, id Software offered a small workshop to a few developers with the goal of licensing the engine. The effort failed, but I am certain this was the first attempt to license such a technology.” In fact, the attempt wasn’t a failure — the engine was licensed to Apogee and used to develop Bio Menace, released in 1993.

While no one understood its significance at the time, this technique shaped how games today are made. “The impact of game licensing on games resembles that of the studio system in film-making, or network programming in television,” Lowood said. “It’s difficult to imagine digital games, especially PC games, without it.”

IndieCade 2013 - 20 Years of Doom - Building the Engine

“Like these other innovations, game licensing changed the structure of the game industry in a way that encouraged different ways of making games,” Lowood continued. “But just as important, game licensing became the basis for a more efficient and consistent way of making and marketing games.”

This being said, Romero’s intention was never to disrupt the industry. He simply wanted to make great games. He remains steadfast in his belief that the pursuit of new technology means very little if it isn’t in service of good design.

“We’re flattening out now with 3D graphics,” said Romero. “People are jumping into virtual reality because there’s nothing else happening. They’re hoping that VR will be the new, groundbreaking thing — but it’s all about design.” It’s clear that this legendary figure still sees video game technology as a means to an end, rather than something that’s worth pursuing in its own right.

“Are people going to see Star Wars because of how it was filmed?” Romero asks. “No, they’re going to go because it’s Star Wars.”

Brad Jones
Former Digital Trends Contributor
Brad is an English-born writer currently splitting his time between Edinburgh and Pennsylvania. You can find him on Twitter…
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