Macintosh Game Continuum 1.04 Download Page

(Read a personal description of Backblaze here.)

EXPLANATION: When the very first Macintosh computer came out (128K RAM, 400k floppy) in 1984, my brother Randy Wilson wrote a video game called originally "Gravity Well" internally, and eventually "Continuum" when it was released (when released it was unable to run on the 128K Mac, instead it required the very next upgraded model of 512K).  I helped a little here and there with encouragement and some graphic design.  Back in 1985 "Graphic Designer" didn't mean the same thing as it means today.  :-)  A (relatively poor) port done by a contractor was released commercially on the Commodore 64 under "Broderbund Software" title and made us a few dollars.  This was probably around 1986 (?). We finally got out of our contract with Broderbund (who never released the game on the Mac) and released the Macintosh Video Game Version of Continuum (the original) around 1987.  We released it "Beer-ware", mostly a joke about how share-ware never works, but we actually got some beer in the mail which was very nice of people.  We even got a bottle of  Sake all the way from Japan!  Since this was pre-internet, it was distributed just by trading it person to person, and was relatively successful that way for us.

UPDATE 4/3/2017 - we exchanged some emails with a few people and I'm going to throw those longer explanations at the very bottom of this web page, so scroll down for more stories!

Anyway, it's getting harder and harder to extract these old archives and keep them running, here are a few last screenshots from the game and all of the source code and video game if you are motivated to get it working.

The old title screen before it was released as "Continuum".  See THE VERY BOTTOM OF THIS PAGE for more graphics from the game.

Below is the look it "shipped with" -> those are 3D walls (nowadays we would call them "2 and a half D") with bunkers that shot at you as you flew through it.


CLICK HERE FOR SOURCE CODE - code to look at in your web browser

Continuum.bin - Continuum 1.04, for Macintosh, by Randy Wilson and Brian Wilson

Continuum Galaxy - You need this in addition to the top item.  Don't click on it, as web browsers open it as text, but if RIGHT CLICK on this link and do "Save As..." you can save a target in the same directory as the Continuum.bin above, then you should be able to run Continuum.  Email me if you have problems. 

Planet Editor Docs.bin - Documentation on how to use the planet editor

ContinuumSource.sit - All the source code to Continuum.


A GREAT EMULATOR is Mini vMac to run Continuum: by Paul Pratt.  This allows you to run Continuum on a Windows PC, or X-Windows, or a Macintosh by emulating an old Mac Plus.


UPDATE on 1/6/2015 - a reader (Kevin Stokes) contacted me and said the following procedure works as of now!  THANKS KEVIN!!

======= START OF KEVIN's INSTRUCTIONS ===========

Hi Brian,

I had fond memories of playing Continuum in the lab with my friends when
I was in graduate school. It was tough to find because there is a recent
multiplayer game recently released with the same name. I eventually got the Mini vMac emulator running on Win 7. I had no luck
with getting Stuff It to run, but I found a ROM that worked with
Mini vMac here: I got a .zip of Continuum 1.04 here: So anyway, if I start up Mini vMac, then drag and drop Disk608.dsk,
the virtual mac boots up. Then I can just drag Continuum1.04.dsk
on to the emulator and it opens a folder where I can run it. Anyway, thanks for making that web page, and thanks for a great game. -Kevin Stokes Fairport, NY



======= END OF KEVIN's INSTRUCTIONS ===========



OLDER WRITEUP on the approximate procedure/steps to get the Macintosh Game "Continuum  1.04" working on a modern Intel based Macintosh:

Warning: THIS HAS NOT BEEN TESTED -> please contact me if you successfully get this working!!

1) Install an emulator that runs old Macintosh 68000 binaries on your new Intel Mac running Mac OS X. Here is one example:

2) Get an old Apple ROM image for the above emulator. Explanation: The above emulator has a legal problem -> it cannot ship copies of Apple's ROMs, so you must somehow find a copy of an old Mac Plus ROM from 1985. Try Google'ing for "vMac.rom" and
then chase it down. It should only take you 5 minutes to find one this way.  I'm no lawyer, but I think to legally run this, you must own a Mac Plus.

3) Get an old Apple System 6 or System 7. Same sort of legal problem as above ROM.  Interestingly enough, I think Apple ships free versions of it's old System 6 here:

4) Hobble it all together, make sure you can boot your System 6 68000 based emulated Mac and browse around in the finder.

5) Save Continuum.bin into your new 68000 based emulated Mac.  Put Continuum Galaxy and side by side with the Continuum.bin.

6) Double click on the "Continuum" binary inside the emulator and run it.

GOOD LUCK -> and tell me if this works.


More graphics and screenshots BELOW:


Here are some of the final "bunkers" that shot back at your ship.  The checkered beach ball was a refuel station.



The final look of Continuum:



Your ship was a small "Asteroids Type" graphic, the final product was not one of the ones below, these are some designs from a graphic artist at Broderbund we never used.

Below are more examples from the Broderbund artist circa 1985 or 1986.  We incorporated some of these into the game eventually.


Below is a documentation "Help" page for the Continuum Planet Editor. 


BELOW HERE are some random essays Randy and I wrote about our experiences developing a video game when we were 19 years old:

Question: Why did you ultimately decide not to release Continuum commercially, or even as shareware?

Answer by Randy: We had a contract with Broderbund, who actually paid us a $5K "advance" on the game royalties to complete the game. They also paid a graphic designer to create better graphics for the ship, bunkers, etc., all of which we used in the final version that we released, except for the ship itself which was too difficult to tell which way it was pointing when you were looking all over the screen and bunker shards were flying around, etc. It was also ported to an Atari game system, but the resulting game wasn't very close to ours. I understand it didn't sell very well. Side story: the Broderbund engineer who ported Continuum to Atari changed from a male name to "Catherine" during the time we were associated with Broderbund, which was the first time I had ever heard of that. I went around for awhile telling everyone how crazy California must be if that happens there, until someone took me aside and patiently educated me about transgender issues. 

Anyway, after awhile it became clear that (1) it would take a lot of extra polish around non-game-play pieces to be able to sell the game at Broderbund's normal level of polish, and (2) Broderbund wasn't thinking it would sell well. So we parted ways, they let us keep the $5K advance and all rights and the graphics, and we had control of the game again.

At that point I was getting ready to go to grad school so I would be too busy to finish developing the game, and Brian didn't want to take it on himself. So we decided to clean it up enough to put out as shareware, which seemed "the way to do things" as an independent developer at the time. But we also had heard that shareware didn't really make any money, so we figured we would make fun of the system by releasing it as "beerware": you were supposedly required to donate a six-pack of beer to us if you liked it. But the language was designed to make it clear to anyone paying attention that we were joking, like the statement that if you weren't old enough to buy beer, you could send us footrubs or promises of firstborn. As long as we weren't going to make any money from Continuum, we figured we could just have more fun through "beerware", and still not make anything.

Question: Continuum is very much its own thing, but it feels strongly influenced by the game Gravitar. If this is accurate, is Gravitar a particularly important game to you? And were there other major influences?

Answer by Randy: There was a local convenience store in Brian and my hometown (Corvallis, OR) that had a Gravitar game in it. Brian got hooked on it first, and then he introduced me. Besides, he was always more comfortable spending money - I thought the only thing you did with money was save it. We would stop in sometimes and play 4 games (a dollar's worth of quarters). I think we loved the feeling of gravity affecting you while played; many times you could take advantage of it by assuming gravity would turn your direction around some obstacle while you could point in the direction of the bunkers and kill them. It added a wonderful touch to the typical asteroids shoot-em-up game.

Originally we called our game "Gravitar", but once the prospect of actually selling it came up, obviously we had to change the name. Besides, the game had never implemented all the pieces of Gravitar (for example the spaceship that flew above you and shot at you), while adding significant other pieces to the original concept, such as much better graphics, the 3D look, and the planet editor. (Did Gravitar have bouncing walls?) Obviously gravity was still a big piece of the game, so we sat around brainstorming other names. Einstein's space-time continuum is an alternate formulation of how gravity works, and we liked how "Continuum" sounded, so it won.

Another big influence was the Mac game Megaroids, which was an implementation of Asteroids for the mac, and using the Megamax C compiler. In particular, Megaroids put a high priority on game responsiveness: when you hit the controls, the ship would respond immediately, not with the slight hesitation you saw in many other games of the time. Responsiveness was a top priority for us as well: a player should never feel like you hit the key in time but the computer didn't respond quickly enough. Megamax released the source code for the game, and we pored over the code, learning many techniques from how it worked. We used Megamax C to implement Continuum for those reasons, and because as college students we wanted something cheaper than the official Apple development environment.

Question: What were some of the difficulties you faced while developing a fast-paced arcade game for the Macintosh?

Answer by Brian (originally written for a different person):
I was 18 years old and it was the summer BEFORE I entered college. Randy (my brother) at 20 years old had complete two years of college before he started the game (I can’t remember). He majored in Computer Science at Harvard, and Harvard had done something really interesting....

They wanted to teach assembly language programming on the Motorola 68000 processor, and the cheapest computer with that processor was the brand new Macintosh in 1984. So Randy learned assembly language on the Mac the year it came out,
taught at Harvard. Not the graphical user interface mind you – assembly! Back in those days, the only way to get the performance you needed was assembly language, so he was uniquely positioned
to make a game at that very moment in time.

If I tried to build it today I’m sure I could do it with modern development environments and modern processor speeds, but Randy pulled it off on something magical with less compute power than a modern digital watch in assembly language with no debugger and it fit inside 128K of RAM. Not 128 MBytes, I’m saying 128,000 BYTES. Including the friggin’ graphics. Eventually it got inconvenient to support the 128K so we finally abandoned it to “only” support the 512K RAM macs and above. A one line program compiles to more than that now.

The computer I’m typing this on has 16 GBytes of RAM, so exactly 125,000 times as much RAM as Randy had available. I think the 1985 Mac had an 8 MHz clock. 8 Million instructions per second. Although honestly I don’t know what these modern processors are doing with 4 billion instructions per second.

I remember when Randy had a crashing bug, what that meant was it would take his Macintosh entirely out – reboot time. There was no memory protection at the time. To figure out where the bug was, Randy would insert System Beeps as the game started up. We would sit there and count the beeps – 1, 2, 3, <CRASH> and narrow it down. In a modern development environment the same bug would be found in less than 5 seconds – Crash, view stack, stair at Java source code – “oh” – fix it. We were working with stone knives and bear skins.

Sounds pre-sound manager.... another story is that we did not have digitized sounds, I’m not quite sure they existed in 1984 and we certainly didn’t know about them. Randy algorithmically came up with zeros and ones to send to the speaker thinking we understood enough about sound waves to make the correct sounds. We were wrong, but through trial and error we would find different sounds and say “wait, that won’t work for the explosions but it is a high pitch whine, let’s use it for the fuel pickup noise”. This is the reason the modern emulators often don’t play the sounds correctly – Continuum isn’t programming to the (eventually released) sound manager APIs – it is toggling speaker bits that are memory mapped into the memory somewhere that hasn’t actually existed since 1987 or so.

Final story – Randy and I could only afford the 512K Macintosh when we were developing the game. Before we released the game, Apple released the Macintosh Plus with 1 MByte of RAM on January 16, 1986. We didn’t know if the game would run on it, so we did something I laugh at now. We walked into the Apple retail store in Corvallis Oregon and pretended to be there as customers, and when the clerk walked away I blocked the Clerk’s view by standing in front of the machine while Randy whipped out a floppy disk from his shirt, shoved it in, we ran the game, played, everything seemed to work, so we ejected the disk and walked out of the store trying “not to get caught”. We repeated this with the Macintosh II release in 1987. The whole thing makes me laugh, because I realize now if we had simply admitted why we were there and explained ourselves the Apple employees would probably have been glad to let us test the game. But we acted like criminals getting away with something. The analogy isn’t quite right because we knew we weren’t harming them and there was a higher calling here, we wanted to bring this game to life despite having no money to purchase expensive test hardware. We were just young and socially awkward.

Question: Continuum is an incredibly challenging game. Was this a deliberate choice on your part, and is this why you included cheats?

Answer by Randy: I think a lot of the difficulty for beginners comes from having to master the controls. Most of us grew up playing Asteroids, which had the same controls, so we almost instinctively knew them.

In designing all the levels, our goal was to accommodate everyone. So the first few levels were designed to be super easy, so that beginners could have some time to get the feel of the controls. Then you got into a long list of levels that most average players could play, and sometimes lose a ship on them. If you were really good, you could get through without losing a ship. Since you gained a ship after every level, good players could "save up" for the more difficult, later levels. But we really didn't want anyone to ever be able to "win", so the last few levels were insanely difficult. I don't know if anyone ever finished them in a real game, but I can promise you that Brian or I or one of our friends got through every level at least once.

Yes, that's part of why we built the ability to start at a given level. After all, there were 60 levels, so you would have to play for a long time just to get to ones you haven't played before. So being able to start anywhere allows someone to play around, practice on other levels, etc., but obviously it didn't count for a "high score" unless you started at the beginning.

Another piece of our philosophy was that shooting and killing things was fun; "I wanna go in flaming hot death" was our motto. So accordingly, you should never have a reason why you shouldn't shoot. That meant that shooting shouldn't take energy, you shouldn't be able to shoot yourself (with bouncing walls), and you shouldn't ever run out of bullets. At one point we considered having a "good bunker" that you would lose points if you destroyed it because it had civilians in it or something. But that idea was nixed because now you had to pay attention: you couldn't "go in flaming hot death".

Question: Was it difficult designing 60 levels for the game?

Answer by Randy: Not after we wrote the planet editor. Brian and I each had a bunch of people playing the game at our respective colleges, and all of them were excited to try their hand at creating levels. We probably got 40 levels from our friends; a bunch them turned out to be garbage, but even those often had gems of creative ideas in them that Brian or I were able to turn into levels that we published with the game. I think our original goal was 50 levels, but we got to the point that we couldn't remove any more of them without feeling like we'd be missing something, so we ended up with 60.

I think publishing the Planet Editor was also a cool attraction to Continuum. Anyone who played for awhile got the itch to create their own challenges, and the Planet Editor allowed people to try that themselves. There were several alternative "Galaxies" that came out, and at one point we considered distributing some of them with the game itself. But by that time we barely had time to keep the game working on the different mac versions that were coming out, so we pretty much dropped support for Continuum altogether.

Question: I notice there are a few more "creative" levels among the bunch, such as the one with man being shot by the gun. Did these act as a fun break from designing more traditional levels?

Answer by Randy: Those came from our friends' ideas, for the most part. We sat around a lot playing and having fun with the game, and sometimes fun ideas would pop up.

Question:  I know you got a few cases of beer from it, but how many foot rubs and firstborns did you get from Continuum?

Answer by Randy: Zero. There was probably lots of head-scratching that went on in various people's houses after they decided they wanted to pay us for the game, and we got lots of confused letters from people, along with checks for $10 (a typical shareware request at the time) and sometimes up to $50. We ended up receiving close to $5,000 total over the next few years, which totally surprised us. We had about 10 people who actually tried to send us beer, most of which wasn't packed very well, broke open, and got confiscated by the post office, who would substitute a nice postcard informing us that it's illegal to send alcohol through the mail. We had one person who sent us a bottle of sake from Japan (which we received) along with a note that "you can't buy good sake in the United States" so he couldn't send a check for us to buy it ourselves. We also had another fan who brought a case of Swedish beer when he visited the San Francisco area, and dropped it off personally on our doorstep; unfortunately we weren't home at the time so we just got a nice note from him saying he couldn't stay. But most were obviously kids struggling to write a letter, and sending us a check that their parents made out for them.

Overall, I think "beerware" was a smashing success.

Answer by Brian: Once Randy got cash (in "Dutch Gilders" because this was before the Euro) from a person in Amsterdam (The Netherlands) with a note saying "This is about what a six pack would cost here."  We laughed and I still have the bill! 

Another story by Brian - when I was attending a Stanford's Master's degree in Computer Science and Randy was just finishing his PhD in Computer Science it was 1990.  A guy named Stuart Cheshire reached out to us saying he was also attending the Stanford PhD program in Computer Science and he wanted to invite us by his apartment to show us his game and buy us a beer he owed us (he actually served us tea).  We really didn't know what to expect, but what Stuart showed us was pretty amazing.  It was a distributed network'ed video game called Bolo YEARS before anybody else had done anything close (other than Maze War I suppose but this was much much more sophisticated). Half the game was running on a BBC Micro that had it's top propped open and a fan pointed at it to keep it from overheating.  The other half ran on a Macintosh and Stuart was almost done with the "port" to Macintosh.  The network between the two computers was a custom (serial) cable built by Stuart.  Anyway, THE WHOLE POINT of this long winded story is that Stuart and myself became life long friends.  Several years later, Stuart's wife Pavni and I built a software startup together called MailFrontier which sold for $32 million.  So in a very concrete way you can trace the fact that Randy and I built Continuum to making millions of dollars, just not directly through the game itself.  Life is chaotic and sometimes the silliest (most naive?) things that wasted years of your life turn out to be the smartest thing you ever did.


(Read a personal description of Backblaze here.)

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