Please login to submit a screenshot

Title SWIV
Game Type Shoot-em-up
Players 1 or 2
HD Installable Yes (With Patch)
Compatibility A500 (All With Patch)
Submission Mike West

Review
As helicopter shoot'em ups go, this has to be one of the best. Looking
down from a birds eye view, the first thing to strike you is the detail of
the terrain that you are flying or driving over. Graphically, this is
really nice to look at. You fly up the screen with the background
scrolling downwards. You basically have to stop the waves of helicopters,
tanks, rockets and numerous other objects from getting past.....even
trains with carriages try to get across the screen, and they will all blow
up!

At certain points in the game, the boss craft tries to form in front of
you. Kill it or be killed! If you destroy it, power-ups appear which you
can shoot to change to one of three differing types. (Banshee players will
have seen the same technique).The maximum five shots at once, sprayed in a
sweeping arc is very satisfying. Sometimes you release a force-bubble, use
it or shoot it to great effect.

The game becomes very intense with loads of action happening all at once,
so you need to be pretty quick off the mark. When the game ends, your shot
accuracy is shown, a high score if you're lucky but my own favourite is
the percentage of the game completed although I've only ever managed 54%!
(An invulnerability cheat does exist but isn't that a bit pointless?)

As you progress, differing backgrounds scroll past, all nice to look at.
At points you just start to feel totally overwhelmed by seemingly so many
craft coming at you all at the same time, let them past you though and
there's no going back for them but watch out for any creeping back around.

If you don't want the helicopter, you can also drive a jeep which I
always find quite difficult to control once the action hots up although
playing this with a mate is a great laugh. Another nice touch is when you
come to water, you hop into a little waiting boat to get across. When you
steer to the next landmass, you then convert back to the jeep.

This is a great game, one I liked as soon as the first time I played it
many moons ago; a real top ten classic in my view. When I first got my
A1200, I was pretty horrified to find this as being one of the games that
stubbornly would not play however much I tried to degrade. A massive
thankyou to Bert (WHDLoad) and Mr.Larmer for the patch to make it install
on the A1200. Eventually, I actually bought my A500 back and this game was
the first to go on it!!!!

Between this and it's brother Silkworm, as much as I like Silkworm, this
is my favourite. If you haven't got this, it's available from Alive as
part of a compilation, a superb game and well worth having.

"In the beginning..."

As far as I can remember, this is the first game I ever played that I really liked. It's a shmup that puts you in the cockpit of a helicopter or in the front seat of a jeep before proceeding to throw hundreds of thousands of enemy vehicles your way. They are all shooting at you and so you decide to shoot back at them – it's as simple as that.

Imagine any vertical-scrolling shooter: Xevious, 1942, Star Soldier, Raiden, Radiant Silvergun or the colourific Ikaruga. Most shmup fans have heard of most, if not all of these games. Why is it that Swiv doesn't make this list? Well, most shmup fans reckon it's not worth their salt. Personally speaking, Swiv is up there with the rest of them. It was my first love and if it wasn't for blowing up virtual ****, who knows where I would be today.

Shmups tend to be pretty. Swiv's graphics were passable back in 1991 and they are still acceptable by today's standards for retro games. Sound? Ergh. Firing off rounds of missiles or any of the other eight(?) weapons (plasma, flamethrower, the usual gear) sounds like... a platformer game... when the cliched hero jumps or hurts his head. It's totally off. Sure, it's a nitpick, but shmups need god-awesome sound, okay? BGM gets off on a better foot, but it still isn't as energetic as Swiv's contemporaries.

The best thing about this game is co-op. Before there was TimeSplitters 2 and The Warriors (Bugs Bunny & Taz too, if you're as crazy enough as myself to like that sort of stuff), Swiv brought some solid two-player simultaneous combat to the world. Sure, virtually every other shmup did the same, but Swiv was unique in that one person would control the helicopter and the other would be riding along in the jeep. The helicopter pilot would be tasked with maintaining air superiority (just like with your typical vertical-scrolling shmup), blasting away at everything in sight whilst avoiding shining bullets and other hot ammo that present as one-hit kill hazards. Player one (you can choose sides, though) has the easier ride of the two. Player two who stays close to the ground has to manoeuvre around buildings and land-based cannons, not to mention steaming locomotives. As compensation, the jeep driver can shoot multi-directionally, strafe-firing as needed. Plus, he can also perform semi-cool jumps across rubble, or if feeling lucky, leap right over those trains. Awesome!

Dual playing as different vehicles means that you really have to work together with your partner to come out right. The jeep will have a hard time passing by a mountain of cannons while the helicopter, with the inability to shoot anywhere but directly in front, will easily fall prey to enemy units that approach from the backside. You really have to cover each other's asses. It would seem like a solo run would be an absolute nightmare to finish – it is. Here's a good challenge for all you elite gamers out there!

Yeah, Swiv rocks. It's not earth-shattering, but it contains enough stuff for you to blow up so that it does rock. There are plenty of weapons to pick up and most of them are upgradeable (spread shots are all I need). Co-op play was the Gears of War experience of 1991, minus the ridiculously good-looking graphics, and it's still fun to play today. There are a number of big bosses that take an unbelievable amount of hits to bring down, but man is it satisfying when they finally explode into a million pieces of chunky pixels. Swiv was my first and it will forever hold a special place in my gaming heart - it really was a perfect introduction to video games.

VERDICT – 7.5/10 The game which got me gaming. Thank you Swiv!


Reviewer's Score: 7/10 | Originally Posted: 10/17/07

Game Release: Swiv (US, 1991)

Who came up with the name SWIV and at what point did you settle on the name? And what does it mean? (The internet varies between Silkworm IV, Silkworm In Vertical, Special Weapons Interdiction Vehicles). What did the actual team call it?

The actual team called it SWIV! We were going to develop a sequel to Silkworm. I proposed to call it Silkworm 4, instead of Silkworm 2, only because I thought it might be a little more unexpected. Create a little bit of intrigue. But soon it became clear that we could not legally use the name Silkworm. Internally, we had already nicknamed the project SWIV. I believe Dan Marchant started that trend. He also came up with several alternative origins of the name, such as you mentioned, and more. He made sure that magazines got conflicting explanations. A great move because it got people intrigued and talking - back then and apparently to this day.

Was the Amiga version of SWIV the lead version?

Yes, very much so.

How much design went into the game before you started coding, or was it constantly developing during the natural life cycle of the game?

There was very little formal game design. I first developed the map editor, and the game grew from there.

I thought I'd have a fresh look at the game so fired it up in WinUAE and looked at the copperlist. I couldn't believe my eyes that the game is running in 4 bitplane mode! Ned Langman did incredible work with 16 colours! (+ sprites for bullets)

Ned's genius usage of such limited resources was very much key to the success of this game, and others that we made during this period.

Were 16 colours chosen so it could be easily ported to the Atari ST? Or was that all Ned wanted/needed to create an awesome atmosphere?

No, the choice to use only four bitplanes was made for memory and performance reasons. If I recall correctly, the Amiga's CPU would run slower if more than four bitplanes were used. And of course the use of a five bitplane frame buffer takes a lot more memory. And I just remembered another reason. If you use a 32 color screen, 12 out of those 32 colors are used by the hardware sprites! And due to the way I wanted to multiplex the sprites, those 12 colors had to be four repetitions of the same three colors: white, gray, and pulsing yellow/red. So in 32 color mode instead of 16, we could have used only four additional colors for the backgrounds, plus white, gray and pulsing yellow/red, or I would have had to sacrifice the hardware sprites. And as you can see, we got a lot of mileage out of those 8 sprite channels.

But if you look closer, you will see that there are a lot more that sixteen colors in the game. The four bitplane frame buffer uses hardware scrolling. It is not redrawn. There is a fifth bitplane, that is enabled for only eight scan lines, to display the non-scrolling score and status line.

But by far the most important enhancement was the fact that the copper was programmed to switch the colors in the palette, on any line in the map. So the top and bottom of the screen could have completely different palettes. This allowed us seamless transitions between areas with different colors. So we have the desert with browns and yellows, the sea with shades of blue, grassland with greens, lava with reds, and so on. Ned made very clever use of this.

How long did the game take to write?

We started immediately after The Ninja Warriors came out. That was late 1989, and SWIV came out in early 1991. So it must have been about a year and a half. That was a long development cycle in those days!

The game runs at 25fps. Was that a deliberate design from the start or there was too much action happening to make it 50fps?

We wanted mayhem. We chose gameplay over frame rate.

There are occasional points in the game where it slows down (especially the huge number of stealth fighters that fly over once the first big baddy is destroyed, it looks like the game drops to about 16 or 12fps). Did you think it'd be better to slow down but have a huge attack wave than smaller characters or less fighters?

I've always thought of the attack wave design as a musical composition: there is a rhythm to it, fast parts, slow parts, build up to a crescendo, then calm again… As I said we tried not to compromise gameplay for frame rate. I think players in general are forgiving if a frame rate drop occurs during a "holy cow look at this" moment.

Is the game using the copper-split method where partway down the screen (which changes depending on the scroll) it is effectively "reset" to be the top so you only need one screen for the buffer? Or is it redrawing the entire screen every frame?

The screen is not redrawn. It is made to scroll by the copper. The copper was also used to make the frame buffer wrap around, like you form a sheet of paper into a cylinder. So what is shown at the top of the screen could be the bottom of the frame buffer.

The copper was also used to make better use of the hardware sprites, and (as I mentioned above) to modify the palette throughout the map.

Whose idea was the load-while-you-play system? How long did that take to perfect?

I believe it was my idea. I first developed the technique for Silkworm. The final boss encounter followed the last level immediately, but used a different set of graphics. The boss graphics did not fit in memory with the rest of the level, so I decided to load them from disk, as you approach the final screen. Then I used the idea extensively for The Ninja Warriors. By the time I used it for SWIV, I had done it twice before, and it was almost routine.

How does it work? (I am guessing the game is running mostly from the vertical blank interrupt and there is a main loop doing nothing but waiting for specific points, loading data from the disk and decompressing it over a safe area of memory for the next batch of baddies and tiles?)

That is exactly right.

What map editor did you use or was it a custom written one?

Oh boy. The map editor was a custom tool, and a monster of a project in its own right. For one thing the map is not tile based. It is built up out of sprites. It allowed Ned to place all background elements on pixel positions, and overlap them in any way he wanted. The editor also allowed Ned to place the copper-driven palette changes that I mentioned. And of course it let him place the enemies.

The map for the game is huge! Who created the map? Was a common map used for all versions of the game (ie. 8 bit and 16 bit) with different graphics or different tile sizes meant this wasn't possible?

Ned Langman made the map, with endless patience and precision. Correct me if I'm wrong, but I believe it was the first game to use one continuous map. The maps for the other versions are completely different.

How did you store the attack patterns data?

Ned had to place markers in the map to trigger enemy waves, and position bosses. Movement patterns and behavior were programmed in code.

Was the game fun to write? (It seems most Amiga users remember this game fondly so I hope it wasn't a chore!)

Yes and no. We were genuinely excited to be working on something this cool. After two arcade conversions (Silkworm, The Ninja Warriors), it was the first time that this team (Ned Langman, John Croudy, Dan Marchant, and myself) were allowed to make it all up. The sky was the limit. Well, the sky and blitter performance.

On the other hand, there were a lot of all-nighters, cancelled vacations, missed deadlines, lonely spouses, and trying to convince our boss that we could really pull this off, if we could just get a little more time…

Were there any impressive technical tricks in the game that you are especially proud of?

Oh gosh, quite a few. The size of the map, and all the tricks we used to bring variation in it. The sprite based map. The dynamic disk access.

But let me mention something that not many people have noticed: SWIV uses a software synthesizer. There were several samples, but many of the sound effects are synthesized in real time. Sound synthesis was (and is) a hobby of mine.

The player bullets seem to be created with sprites, and 2 separate sprites for a 'double bullet'. Was this a deliberate design idea so one of the shots could hit an enemy and the other one continues up the screen to hit another target?

Hmm, I'm not sure why we did that. If there is room in the sprite, it would be smarter to have a double bullet graphic. If you want one bullet to continue after the other hits a target, you can always switch it to a single bullet graphic. It's odd. But I'm sure there was a reason for it at the time…

You must have heavily re-used the 8 sprites all over the screen for all the bullets. Is the game repositioning them on the fly as it's drawing the screen?

The copper repositions the sprites dynamically. I don't think I used the control words.

Harry (one of the WHDLoad team that hard drive installs games) noticed that the score panel at the top used some trick that doesn't work on AGA machines and that part of the game had to be re-coded. Can you remember how the score part was done?

It uses a non-scrolling fifth bitplane, and a trick to make it mask out the other four bitplanes, so it looks like it sits on top. The fifth biplane is only enabled for those few scan lines. AGA machines did not exist yet.

How did the score panel mask work? The only obvious way I can think of is to 'OR' the score graphics onto bitplanes 1-4 and have 5 enabled? If you play the game under emulation and switch to AGA mode all the status panel flashes reds, oranges and yellows - the colour palette entries 16-31 for the bullets. So it looks like the trick to make that plane sit on top doesn't like AGA machines.

The 'OR' method that you describe would require the line to be erased and redrawn every frame, at least on the four scrolling bitplanes. Two expensive operations! No, the obvious way to do it would be to set palette entries 16…31 all to the same color. But that would have worked without trouble on the AGA chip set, so I must have done something else… I can't remember. Your knowledge of the Amiga hardware is a lot fresher than mine. I haven't touched the platform for two decades.

Nearing the end of the development you must have known you had a big hit game on your hands. At what stage of things did copy protection come into play? Who chose the protection system (Rob Northen copylock) and did you implement it?

Rob Northen didn't have much competition at the time. We really did not spend much time thinking about it, or installing it.

Did you ever try and disassemble or crack the copylock yourself to see how difficult it would be for hackers?

I don't remember doing that.

Do you have any idea how much a copylock cost for a game?

I was never involved in purchases or licensing deals.

Did you read the SWIV reviews at the time? Were any of those unfair/too low? (I personally think anything under 90% is a travesty!)

Yes, of course I have read them!

But let me tell you, as cool as it was (and helpful for my career) to have had a hit at that time, what really strikes me is how fondly people remember SWIV, even now, twenty years later. That blows me away. So… thank you!

Do you still have the source for this game (or any of your games?)

No. Lost in the mists of time.