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 Features
Postmortem
- Myth: The Fallen Lords
As the team
at Bungie Software put the finishing touches on the Marathon series of
first-person action games, our thoughts drifted to bringing our 3D game
experience to the real-time strategy game (RTSG) genre. We were inspired
by movies such as Braveheart, with its close-up portrayal
of bloody melees between large forces, and books such as Glen Cook's The
Black Company, in which gruesome tales of battle contrast with
engaging and intriguing characters. We envisioned a dark, amoral world
where opposing sides are equally brutal and their unity is torn by power
struggles within the ranks. We dreamed of game play that combined the
realism and excitement of action games with the cunning and planning required
by strategy games.
Our original design document, if you could call it that, was simply opposing
lists of "Stuff that Rocks" and "Stuff that Sucks." Anything vaguely cliché,
such as excessive references to Tolkien novels, Arthurian legend, or "little
boys coming of age and saving the world," went in the "Sucks" category.
The "Stuff that Rocks" list was filled with ideas that contributed to
the visual realism of the game: a true 3D landscape, polygonal buildings,
reflecting water, particle-based weather, "blood-spattered battlefields
littered with limbs," explosions that send shock waves through the terrain,
and "lightning frying guys and their friends."
Our goals for the product were lofty: simultaneous release on Windows
95 and Macintosh platforms, integrated Internet play, and a free online
service to allow players from across the globe to battle one another.
From this vision, Myth: The Fallen Lords was born.
The
Making of a Legend, er, Myth
The project
began in January 1996 with four programmers, two artists, and a product
manager; midway through development, one programmer dropped out and an
artist was added. Music, sound effects, and cut scenes were done out-of-house,
and a few artists were contracted to help with interface artwork.
The roots of the Myth programming team were on the Macintosh,
so most initial coding was done on the Mac with Metrowerks CodeWarrior.
When PC builds were required, though, we used Microsoft Visual C/C++.
Myth was written entirely in C.
In addition to creating the shipping product, we developed four tools
to aid in the construction of the game. One utility, the Extractor, handled
the importing of sprites and the sequencing of their animations. Another
tool, dubbed Fear, dealt with importing polygonal models such as houses,
pillars, and walls. The Tag Editor was responsible for editing the constants
stored in cross-platform data files, which we called tags. And finally,
Loathing, our map editor, handled the rest. Loathing was built around
the Myth engine and allowed us to modify the landscape, apply
lighting, set terrain types, script the AI, and place structures, scenery,
and monsters.
The artists
used Alias|Wavefront's PowerAnimator and StudioPaint on a single Silicon
Graphics Indigo 2 to create polygonal models and render all the characters.
At one point, the artists worked separate day and night shifts so that
they could maximize their time on the SGI. Models were brought into the
game using Fear, while the sprites were cleaned up in Adobe Photoshop
and imported with the Extractor. To create the texture maps for the terrain,
the artists used Photoshop to draw what looked like an aerial photo and
applied it to a 3D landscape in Loathing.
If this sounds like a lot of work to you, you're right. Most maps took
at least a week or two to create. We considered using fractal-generated
landscapes, but we were worried that the inherent randomness of such terrain
would make it extremely difficult to design good levels. As a result,
all maps were painstakingly constructed by hand. As the artists put the
finishing touches on the landscapes, the programmers, who doubled as level
designers, scripted the AI for the levels.
Myth took approximately two years from start to finish. It
began as a six-degree of freedom engine that allowed you to fly around
a landscape. Soon, troops were added, heads started flying, blood was
made to destructively alter the terrain's color map, and the network game
was born. Most of the first year was spent developing the initial network/multiplayer
game play. Almost the entire second year was spent developing the single-player
game, refining the levels, and testing bungie.net, our free online service.
What
Went Right
1. Bringing
carnage to the masses.
It's a real trick to create a simultaneous, identical-look-and-feel, cross-platform
release. It's even harder to do so within the expected time frame with
only three programmers. Our experience porting Marathon,
our popular Macintosh-only action game, to Windows 95 was a valuable learning
experience, and we vowed when starting Myth that, "This time,
we're going to do it right."
Doing it "right" meant designing Myth from the ground up
to be cross-platform compatible. Ninety percent of the code in the game
is platform independent; the other ten percent is split evenly between
routines that handle PC- and Macintosh-specific functionality. It was
a programmer's dream come true -- we spent almost all our time implementing
features and solving real problems, rather than wasting it fighting the
OS.
All of the data for Myth, from animated cut scenes to the
percentage of warriors who are left-handed, is stored in platform-independent
files called tags. Tags are automatically byte swapped when necessary
and are accessed via a cross-platform file manager.
One of our programmers worked in conjunction with Apple Computer Inc.
to develop a cross-platform networking library code-named Über. One
of the greatest things about Über is that it supports plug-in modules
for network protocols. Thus, although Myth currently only
allows games over TCP/IP, AppleTalk, and through TEN, it would be trivial
to add support for new protocol modules. Myth must provide
a user interface to set up the connection, but once Über establishes
that connection, game play over a LAN is the same as over the Internet.
To keep the game's appearance identical across platforms, we implemented
our own dialog and font managers. This allowed us (actually, it required
us) to use custom graphics for all interface items. We designed our font
manager so that it supported antialiased, two-byte fonts, as well as a
variety of text-parsing formats. Thus, our overseas publishers Eidos and
Pacific Software Publishing were able to localize relatively painlessly.
The German version of Myth was finished only a couple of
weeks after the English release, with Japanese and French versions close
behind. The only game experience that is different for the two platforms
is the installation, and two players on bungie.net have no idea whether
their opponents are on Macintoshes or PCs.
2. bungie.net and beta testing.
Myth was also released with integrated support for our first
online service, bungie.net. This service was designed specifically for
Myth and was developed simultaneously. Similar to online
services for other games, it allows players to connect via the Internet
to game rooms, where they can chat or play against one another. The Linux-based
server that runs bungie.net keeps track of player statistics and gives
everyone a score in our ranking system. The service's web site (www.bungie.net)
has access to this database and sports a leader board that lists the top
players.
Our networking layer is based on a client/server model. Once you advertise
a game on the network, you become a server, and other players join your
game. Network traffic during a game is limited to the commands issued
by the players. All copies of Myth in a network game run
deterministically and merely interpret the commands that they receive.
This makes cheating difficult; if you hack the game to perform something
illegal, such as making all your units invincible, you'll go out of sync
with other players. When portions of the game data are periodically checksummed
and compared, a message will indicate that you're out of sync (and out
of luck). So far, the only form of cheating we've encountered is users
trying to exploit the bungie.net ranking system.
To rigorously test our server load capacity and the bungie.net code, we
released a public beta of the network game. We were initially apprehensive
because it was our first public beta test of a product, but it was an
amazing success. When errors occur, Myth alerts the player,
logs the error messages, and usually allows the user to save a replay
of the problem. Testers submitted these detailed bug reports via e-mail
and chatted about features and improvements to levels on internal newsgroups.
Best of all, the testers used bungie.net to give instant feedback to the
developers. This interaction allowed us to gather even more useful information
about bugs, and it made the testers really feel involved in the final
product. By the end of the beta-testing cycle, we not only had a clean
product, but also had a loyal following of users who sang our praises
when the NDAs were lifted.
3. 3D graphics acceleration.
When the project started, 3D acceleration hardware was only just starting
to become popular. Nevertheless, we tried to keep hardware acceleration
in mind when designing our rendering pipeline. When the opportunity arose
to add hardware acceleration, the implementation worked beautifully. We
worked closely with people from 3Dfx and Rendition and added support for
their chipsets in about a week. It's amazing how much these accelerators
add to the smoothness of the terrain, the fluidity of camera movement,
and the realism of the units and effects. These chips rock, and great
on-site developer assistance made them easy to support.
4. Getting back to the people.
Once we had released Myth, we definitely did the right thing
by waiting for player feedback and then releasing a patch to address their
issues. Since our public beta test caught most of the bugs in the shipping
product, nearly all our post-shipping efforts were directed towards adding
user-requested features. We scoured the newsgroups, read e-mail, and talked
to customers about their complaints. From these disparate sources, we
compiled a list of improvements for our 1.1 patch.
All major user complaints were addressed in the patch. We added support
for Rendition and Voodoo Rush cards. We extended the camera's maximum
zoom for a better view of the battlefield. We made our easy difficulty
levels even easier. And we improved the unit AI. By the time the early
reviews came out, we'd already released a beta patch that addressed almost
everything on the reviewers' lists of Myth's failings.
5. Doing more with less.
It doesn't take fifty people to create a major cross-platform software
title. Period. Bungie Software has barely half that number of employees
in the entire company, and we not only develop all our games, but publish
and distribute them as well! Macintosh and PC versions of Myth,
all our internal tools, and our online service were essentially developed
by only six people, and everything shipped on time with no major glitches.
There's no big quality assurance department here at Bungie; the public
did our testing for us, and we listened to them as seriously as if they
were coworkers on the project.
We didn't hire any game designers, writers, or level designers to come
up with our game concept and story line. Myth truly is the
combined vision of our team, and each of us feels that it was our game.
We came to work each day excited about the project, and we're damn proud
of what we managed to create.
What
Went Wrong
1. Staffing
problems.
On the flip side, it became clear very early in the project that we were
understaffed for such an ambitious undertaking. Success or failure rested
with a handful of people, and that was extremely stressful. Losing a programmer
halfway through development added still more pressure during the final
push to get the game out the door. Additional programming tasks had to
be shouldered by the remaining developers, who were already also responsible
for level design. To alleviate the problem somewhat, we even found it
necessary to ask our busy network administrator to aid in AI scripting
and level design.
We did hire a third artist near the end of the project, but it was almost
too late. While his contributions to the final product were by no means
insignificant, it took a long time to get him up to speed. Similarly,
when we dropped the services of our original sound guy late in the development
cycle, a new sound team had to rush to redo all the work.
If you're looking for good anecdotes about how we blew off steam with
wild weekend trips to Cancún, you won't get any. We all worked
incredibly hard, and did so willingly because Myth represented
a two-year labor of love. All the great previews and supportive feedback
from beta testers kept us excited and made us realize that we really did
have something special on our hands. Nobody wanted to slack off and allow
competing products to beat us to the shelves. The moral of the story:
staff up as early as possible and plan to weather the unexpected.
2. Scripting.
The biggest announced feature that didn't make it into the final version
of Myth was a scripting language that would allow the player
to modify elements of the game. We had hoped that user scripts could be
written for extensible artificial intelligence, as well as custom formations,
net game rules, and map behaviors.
We selected Java as a good basis for the Myth scripting language
because of its gaining popularity, good information-hiding capabilities,
and relatively simple byte code interpretation. After several months of
work, early versions of the game loaded, compiled, and ran code from tag
files. A few simple scripts worked for presentation purposes, including
one that instructed a unit to search the battlefield for the heads of
the enemy and collect them in a pile.
Unfortunately, when the programmer responsible for the scripting language
parted ways with Bungie, we were left with a number of features to implement
and no library of user-friendly interfaces with the game code. Given its
incomplete state at such a late stage of development, there was little
choice but to drop this functionality.
3. More frames of animation.
One of the complaints most often voiced by players is that the sprite-based
units' animations are not fluid enough. At the start of the project, when
we planned for the number of frames of animation per unit, there was a
good deal of uncertainty regarding how much RAM would be consumed by large
texture maps, sounds, and other resources. As things were, it was not
uncommon for our landscape textures to reach 5MB in size, and certain
animations already consumed close to 1MB -- our uncertainties were not
unfounded. We erred on the conservative side. Though we implemented caching
schemes that greatly reduced our memory requirements, there wasn't enough
time to rerender the units.
4. Pathfinding.
Perfect pathfinding seems to have become the Holy Grail for games in the
RTSG genre, and Myth is no exception. The game's terrain
is a 3D polygonal mesh constructed from square cells, each of which is
tessellated into two triangles. Cells have an associated terrain type
that indicates their impassability, and they may contain any number of
solid objects, including trees, fence posts, and units.
Ah! Square cells, you say? Having read previous Game Developer articles
(Bryan Stout, "Smart Moves: Intelligent Pathfinding," Game Developer,
October/November 1996; Swen Vincke, "Real-Time Pathfinding for Multiple
Objects," Game Developer, June 1997), your first thought
may be that the A* pathfinding should do the trick. The first problem
with a pure A* approach for Myth is that impassable obstacles,
such as troops and trees, may lie anywhere on the terrain. Penalizing
the cells beneath impassable obstacles is a bad idea because the cells
are fairly large and obstacles are not guaranteed to be aligned at the
center of a cell. Furthermore, even if a tree did consume exactly one
cell, the A* path to avoid it would make a unit walk up to the tree, turn,
and continue around it. Units that bump into trees and walk between the
centers of large cells appear extremely stupid; you really want your group
of troops to avoid obstacles (including each other) ahead of time, and
smoothly weave their way through a forest.
To produce this effect, we created our own pathfinding algorithm. First,
we ignore all obstacles and calculate the A* path based solely on the
terrain impassability. For all intents and purposes, the terrain in Myth
never changes, so this path can be calculated once and remembered. Now,
we consider the arbitrarily placed obstacles and periodically refine our
path using a vector-based scheme. If the planned path would cause us to
hit an obstacle, we need to deviate our path. We recursively consider
both left and right deviations, and choose the direction that causes us
to deviate least from our A* path. Thus, we've considered terrain impassability
information and we can avoid arbitrarily placed (or even moving) obstacles
well before we bump into them.
For every game, pathfinding is a pretty complex and sensitive beast. This
method worked well for 90 percent of our cases, but rigorous testing revealed
certain cases that were not adequately handled. As the ship date drew
near, we were forced to say "good enough" rather than handle these problem
cases and risk introducing new bugs. Our current algorithm works pretty
well and provides the effect we sought, but there's definitely room for
improvement.
5. Features that missed the cut.
With a few exceptions, everything from our list of "Stuff that Rocks"
made it into the final product. Those features that didn't make it came
so close and were so exciting that they definitely deserve mention.
Near the end of the project, we started adding support for 3D fire, which
would be ignited by explosions and flaming arrows. Our flames were sprite-based
3D particle effects, complete with translucent smoke. Fire could spread
across the landscape and move at different rates over the various types
of terrain. To our dismay, when a spark in the woods spread into a raging
forest fire (as it should), all the translucent smoke sprites slowed even
fast, 3Dfx-accelerated machines to a crawl. With little time to rectify
the problem, we had to put out the fire, so to speak.
We had also planned for wildlife to scamper across the terrain and for
birds to fly through the air, breathing life into our empty landscapes.
Our attempt at ambient life started with a giant squirrel created by one
of our artists. Unfortunately, due to time constraints, we didn't have
a chance to create very interesting behaviors for it. Just about the only
AI that we had a chance to code simply made the squirrels gravitate towards
the player's units. We thought it best to drop ambient life rather than
subject players to hordes of nuzzling squirrels.
Post-Release
Reactions
With all
the prerelease hype Myth had received, we were very anxious
to see how the public would receive the final version. The reactions from
beta testers were phenomenally positive, as were the comments from customers
and reviewers. Our swiftness in correcting problems and adding several
user-requested features with a 1.1 patch only earned us more kudos from
the press and public.
But possibly the most satisfying result of the game is the degree to which
it lessens the appeal of playing with a traditional isometric perspective.
Working on Myth so consumed our time that we didn't get a
chance to play anything else; we looked forward to playing some old favorites
and the latest demos of our high-profile competition after we shipped.
It was a real surprise to discover that once we were accustomed to Myth's
3D camera and its associated freedom, playing isometric games was frustrating
-- the action seemed distant and unrealistic, while the view of the world
was annoyingly rigid. This sentiment was echoed in both player comments
and reviews of the game. Since our Marathon products were derided by some
as Doom rip-offs, it was especially satisfying to hear players say that
Myth pushes the genre in a new direction, from which there's
no looking back.
As of late
1997, Myth: The Fallen Lords had shipped 350,000 copies worldwide
in four languages on two platforms. bungie.net currently boasts tens of
thousands of registered users and is being expanded to keep up with the
constantly increasing demand. As I write, it has just been declared Game
of the Year by Computer Games Strategy Plus and Strategy
Game of the Year by Computer Gaming World. It remains to
be seen whether Myth will inspire other entries into the
3D real-time strategy game genre. But if nothing else, Myth
is proof that a very small team with a strong product vision can still
make a very big game.
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