Drug Runner

Preliminary Design Document



First Draft

October 5th 2001


[dave's comments (all in red and bracketed):

star features


scope cutbacks]




alan woo andrew nealen connie fung cynthia lim james haslam serif askin

Table of Contents

1 Concept Issues *

1.1. Game Goals *

1.1.1 Drug Running Missions *

1.1.2 Boss Missions *

1.1.3 Money *

1.2 References *

2 Story *

3 Game Flow *

3.1 Overview *

3.2 Description of Gameplay Experience *

3.3 Flowcharts and Storyboards *

4 User Interface *

4.1 Front End *

4.1.1 Interaction *

4.1.2 Animation *

4.1.3 Sound *

4.1.4 Screen Layouts *

4.2 Pause Menu *

4.2.1 Interaction *

4.2.2 Sound *

4.2.3 Screen Layouts *

5 Game Modes *

5.1 Overview *

5.2 Single Player Mission Mode *

5.3 Multi Player Mission Mode *

5.4 Single Player Time Trial Mode *

5.5 Multi Player Time Trial Mode *

6 Characters *

6.1 Overview *

6.2 Classes *

6.2.1 Player *

6.2.2 Mob Boss *

6.2.3 Police *

6.2.4 Obstacle Vehicles *

7 World / Environment / Levels *

7.1 Overview *

7.2 Structure & Scope *

7.3 Flow *

7.4 World Interaction *

7.4.1 Level 1 *

7.4.2 Level 2 *

8 Game Play *

8.1 Overview *

8.2 Single Player Mission Mode *

8.2.1 Overview *

8.2.2 Control *

8.2.3 AI *

8.2.4 Missions *

8.2.5 Scoring *

8.2.6 Flow *

8.2.7 HUD *

8.2.8 Health *

8.3 Multi Player Mission Mode *

8.3.1 Overview *

8.3.2 Control *

8.3.3 AI *

8.3.4 Missions *

8.3.5 Scoring *

8.3.6 Flow *

8.3.7 HUD *

8.3.8 Health *

8.3.9 Power Ups *

8.4 Single Player Time Trial *

8.4.1 Overview *

8.4.2 Control *

8.4.3 AI *

8.4.4 Scoring *

8.4.5 Flow *

8.4.6 Health (and Replenishment) *

8.5 Multi Player Time Trial Mode *

8.5.1 Overview and differences to Single Player Time Trial Mode *

9 Rewards *

9.1 Overview *

9.2 Unlockables *

9.3 Collectibles *

9.4 Feedback (Sounds and VFX) *

9.5 Easter Eggs *

10 Graphics / FX *

10.1 Overview *

10.2 Cartoon Shading *

10.3 Particle System *

10.4 Billboarding *

10.5 Decal System *

11 Animation *

11.1 Overview *

11.2 Classes *

11.2.1 Characters *

11.2.2 Objects *

12 Camera *

12.1 Overview *

12.2 Gameplay Cameras *

13 Sound *

13.1 Overview *

13.2 Characters *

13.3 Ambient *

13.4 Music *

13.5 Front-end *

13.6 FX *

14 Tunable Parameters *

14.1 Overview *

14.2 Character Attributes *

14.3 World Attributes *

14.4 Object Attributes *

15 Additional Features *

16 Risks / Problems / Concerns *



  1. Concept Issues

    Drug Runner will be a mission-based driving game, similar in style to that of Crazy Taxi, but involving more complex and varied missions, and a pursuit element in a world that will unlock as the player progresses. The game will take place in a futuristic urban setting with a dark, yet comic-book style appearance. Vehicles will be rendered using a cel-shading technique to add a "Batman" like atmosphere to the game. The climax will occur when the player is tasked to kill his/her crime boss by running over him.


    1.1. Game Goals


    The overall theme of Drug Runner is to accomplish specific missions, which will involve driving about in a futuristic urban city to deliver drugs or other such underworldly tasks. After enough missions of sufficient difficulty have been accomplished, the player (herein referred to as "the drugrunner") will be required to finish a "boss" mission to unlock a further portion of the city. After all portions of the city are unlocked, the final boss mission must be accomplished to finish the game. Each completed mission will add more money to the drugrunner’s coffers. Of course, more difficult missions will give the drugrunner more money. Upon finishing the game the player is ranked upon how much money is in his/her bank account.

      1. Drug Running Missions

        These missions apply to both single-player and multiplayer modes.


        The drugrunner will have a preset amount of time to drive to marked locations within the city in order to accept missions. The missions will then define a number of further locations in the city in which drive to. Upon accepting the mission, the crime boss will present the details on exactly to do and why this mission is important. For example, the crime boss might tell the drugrunner that "this evidence needs to be dumped, and fast. Drive to the dump and drop the murder weapon into the trash." The missions will have varying difficulty and proportional reward.


        The mission then needs to be completed in a preset amount of time, or the drugrunner’s bank account will be deducted an amount of money. Should the player not have a sufficient amount of money, to cover the loss, then the player will die. On more difficult missions, running out of time will result in immediate death.


        While performing these missions, the drugrunner must be on the lookout for police, who will, if they catch you by smashing into you, deduct an amount for a bribe from your bank account. The same bank account rules apply here as in mission failure.


        A further danger is avoiding obstacle vehicles, which will be school busses, cars, trucks, etc. Hitting an obstacle vehicle or an inanimate object such as a building will result in damage to the drugrunner’s car. The performance of the drugrunner’s car may suffer as a result.


        The ultimate goal of the game is to unlock the entire driving area by completing enough missions, and to kill your bosses, thereby winning the game. The best Drug Runner players will have to attempt missions in different permutations in order to earn the most money and achieve the highest rank.




      3. Boss Missions

        These missions only apply to single-player mode.


        Once enough driving missions are performed of sufficient difficulty, the player will required to perform a "boss mission". This is where the player tires of "working for the man" and attempts to move up in the crime syndicate by killing his immediate boss. Completion of the first boss mission will unlock a further portion of the city for exploration and play. Completion of the second boss mission will win the game.


        The boss mission will involve finding the bosses’ vehicle that is driving around somewhere in the city. Once the drugrunner has found that rat-bastard boss of his, he should attempt to destroy his bosses’ car by repeatedly ramming it. The boss will attempt to get away, and may curse, but the drugrunner must keep ramming until the bosses car is destroyed. Once his car is totalled, that swine will then exit his vehicle and attempt to flee on foot [dave's comment: character animation!]. It is at that point that the drugrunner will try to complete the boss mission by running over the boss. Squish! Try THAT in crazy taxi, Buster!


        The reward for killing your boss: If it’s the first boss than the reward will be a big pile of cash and an expanded play area. The second boss killed off will again give you cash, but also win the game!!!

      5. Money


      Every mission will add cash to the player’s bank account. More difficult missions will be worth more money. Boss missions will be worth the most money.


      Players with the most money by the time the game ends will wind up on a high-score list.


      Money can be also be used as penalty. For instance, if caught by police the drugrunner will have to bribe them to stay out of jail. For certain missions, not completing them in time will also hurt the piggybank. Monetary penalties will happen automatically.


    1. References


    Please refer to the following websites for further gameplay and atmosphere details:


    Batman comic book: http://www.batman.com

    Crazy Taxi: http://www.crazytaxi.com


  3. Story

    You have just graduated with your philosophy degree. Unlike previous years, the class of 2141 faces a significant economic downturn and there is little demand left for your platitudes nor considerable driving skills. You decide your talents could be best spent leading a life of crime, so you set your sights on moving up the ranks of the city's criminal cartels. One problem: you're pretty much broke and only have a corroded Mazda 30303 to your name.

    In desperation, you decide to accept your first ‘job’. Now drive to the site where the jobs are offered and listen to what your boss has to say. He’ll tell you where to drive and what to do. Careful! If the jobs you accept don’t get done in time, you'll anger your mob bosses, possibly ending up more inert than Jimmy Hoffa. [long comment from dave: are there 'bad' missions - i.e. too difficult - if yes, how do you know / need specific equip/power to complete particular mission] Also, there are numerous police roaming the city who, if they should catch you, it will cost you a cash bribe to keep your ass out of jail. If they catch you doing a particularly nasty job however, it’s straight to the clink for you!


    Accomplish the driving missions to your bosses' satisfaction however, and you will be rewarded handsomely. Little do they know however, you have eyes on their positions within the city’s extensive crime syndicate. You promise yourself that, if you ever encounter them in person, that you will run their car off the road, and squish them with your Michelins.


    It’s a big city out there, controlled by powerful characters. You must respect your territory of operation in the city. Only after becoming big enough in the mob can you move out of your area and take jobs in the city at large. Only one way to do that…. Hunt down your immediate boss and take care of him.

    One last thing, your car is now your livelihood. Don’t smash it up too bad by running in to civilian busses, cars, etc. that are roaming around, or you won’t be able to get around as quickly.


    Now, fasten your seatbelt, Poncho. There is a lot of money to be made and this city’s junkies desperately want your help!


  5. Game Flow
    1. Overview
    2. The game starts when the user runs the executable of Drug Runner. The first screen that pops up shows the logo for the game. The player can skip the next screen, which explains the story behind Drug Runner, and go directly to the startup screen. On the startup screen, the player is given several choices: 1) start game, 2) edit options, and 3) exit game.


      Normally, the player will choose to start game. The next screen that pops up will allow the player to choose the game mode. There are 4 game modes: 1)single player mission mode, 2)single player racing mode, 3) multiplayer mission mode, and 4) multiplayer racing mode. Game play experience differs for each game mode.


    3. Description of Gameplay Experience
    4. In mission mode, when the game begins, the player can see the locations of missions and his/her current location on the transparent HUD at the upper right corner of the screen. The player will choose a mission, and drive to the location where that mission will be assigned. Once the player drives through the mission location, the mission will be revealed in the textbox on the screen, along with the boss' commanding voice message. The player will continue to take on jobs until all available jobs in the city district are completed. Then, the player must find and kill the boss in that district within a set time. The game is finished when the player has completed all levels, or if the player fails to complete a mission or get caught by the cops. In between levels, there will be bonus levels in which user is to take on certain jobs. In bonus levels, the player can gain more money for upgrading his/her vehicle.


      In race mode, basically, the player can race specific predetermined paths in the city. The player will try to beat the best time for that particular race path. The game is finished when the player has completed the race, or if time is up.


      In any of the game modes, the player can choose to exit game at any time. For details about the game play modes, please go to section 5 on Game Modes.

      [long comment from dave on 3.1 and 3.2: eventually you must rate importance of intro, importance of number of modes, importance of levels and sound effects]



    5. Flowcharts and Storyboards



    Figure 3.3.1 Flowchart of gameplay

    [dave's comment on figure 3.3.1: good!]

    The flow chart shown here illustrates the basic game flow of Drug Runner.



  6. User Interface
  7. Overview

    The game interacts with the player in two major ways. First, the player can navigate through the introduction screens and startup screens before the actual game commences. These screens mostly provide the player with choices for configuring features of the game, setting up player's personal information, configuring controls such as input and sound, starting and exiting game.


    1. Front End
      1. Interaction
      2. Most of the front-end interaction involves the player using the mouse and the keyboard. The mouse is used only for navigation and selection purposes. The player will use the keyboard for inputting data information, and for maneuvering the vehicle around in the city districts.


      3. Animation
      4. Most of the animation in the game is used in the introduction of the game. Some animation might be used for providing extra information and tutorials about the game.


      5. Sound
      6. The player can choose the style of sound used for the front end. Each style has a template of sounds, which are used when events are invoked. These events include things being clicked-on on the screen, and systems errors invoked while the game is in focus. For details, please go to section 13 on Sounds.


      7. Screen Layouts

      Figure Startup Screen

      This screen will be the first to be shown when the player opens up Drug Runner.

      Figure Game Modes Screen

      The player has the option to choose game mode after the player starts the game.


      Figure Personal Profile Screen


      Figure Single Player Mission Mode

    2. Pause Menu
      1. Interaction
      2. During the game (in any of the four game modes), the player can choose to pause the current game by either clicking on the pause button on the screen, or by pressing ‘p’ on the keyboard. To resume a paused game, the player can click on the resume button on the screen, or by pressing ‘r’ on the keyboard.


      3. Sound
      4. Some ambient music will be played in the background while the game is paused.


      5. Screen Layouts


    Figure Game Paused Screen



  8. Game Modes
    1. Overview
    2. The Game will include four game modes. Two of which are single-player and two multi-player.

    3. Single Player Mission Mode
    4. This will be the main mode the design team will focus on during development [dave's comment: good!]. It is the teams’ goal to implement this mode fully tweaked before too much work is invested in the other modes of gameplay.

      In single player mission mode the player initially controls a low-fidelity vehicle and starts with only little cash and a time counter counting backwards. The car might not be the fastest, but at least it is still undamaged. The player is ‘given’ a vehicle and does not have the option to select one from the front-end menu. He/She is thrown directly into the action, giving the gaming experience an ‘arcade like’ feeling. Using an alpha transparent HUD with a city map (described more in detail later), the player must select from various ‘missions’, which are color coded on the map. Some missions may involve simply ‘picking something up’ by driving over the checkpoint and dropping it off by passing another checkpoint. Other more sophisticated missions can include bringing the car to a complete stop in the checkpoint area and having to wait on people, such as bank robbers trying to get away from the cops. Depending on the nature of the mission, it is categorized in three difficulty classes, ranging from green over yellow to red on the HUD, which is also reflected in the scoring system. The car can take damage from hitting other vehicles, buildings or other obstacles mentioned in the ‘characters’ and ‘world’ sections of this document. On fulfillment of an assigned job, the Player receives more time, more cash and repairs to his/her car. There will be police cars underway, trying to catch the player should he/she be seen. In case a police car stops the player, a bribe is expected. Should all missions be completed, then the player must beat the boss of the level, by hitting the boss car often enough to force the boss out of the car and then drive over him! This then unlocks a new vehicle and new areas of the city. The game ends when time runs out or all levels are completed. The cash sum is calculated and a school grade rating is given based on the accumulated time and money during the game. The initials of the player are kept together with the rating and cash in the persistent high score list. For more detailed gameplay, see the ‘gameplay’ section.

    5. Multi Player Mission Mode
    6. This mode will be similar to the single player mode, with the difference of a vertically split screen with two players competing simultaneously. All areas and vehicles unlocked in the single player mission mode are available to the multi player mission mode via the multi player setup in the front-end menus. The time limit is gone, so emphasis is put on completing the missions and accumulating as much money as possible. There will be equal amounts of missions of each difficulty level scattered throughout the city, to keep the game balanced and strategic, yet the players must select wisely based on their skills as they might still be in need of repairs due to car damage. The game might end before all missions are accomplished, as a vehicle is destroyed if the damage level reaches 100%. A few power-ups will make interaction between the opposing player’s quite interesting (see ‘gameplay’ for more details on power-ups). At games end, the player with the greater amount of cash wins. There are no ‘boss’ fights as in single player mission mode. No high score list is kept of this game play mode.

    7. Single Player Time Trial Mode
    8. The game will include a time trial mode, in which the sole purpose of the game is to race around the city along a predetermined path and complete three laps as fast as possible. All obstacles that exist in the single player mode also are included in this mode. Additionally, AI controlled police cars will try to block the player and try to reach the goal themselves. So one must not only be fast, but also evade the pursuing police cars to minimize car damage, which will result in reduced top speed. The city is grid based (see section ‘world’), so multiple paths can be possible throughout the city, possibly allowing multiple options to get to the goal. Best times of players are stored in a high score list along with the track chosen.

    9. Multi Player Time Trial Mode

    Basically the same as the single player time trial mode, but with a vertically split screen to allow two players to compete simultaneously. In this mode (as in multi player mission mode) power-ups will exist to make for more interesting competition between the opponents. Police cars can be optionally switched off in the menu, as this mode of gameplay is not stored in the high score list.



  9. Characters
    1. Overview
    2. There are four main classes of characters in Drug Runner: players, mob bosses, police, and other characters [dave's comment: the cars are characters] [andy's comment: yeah, we talked about that and also considered cars to be characters in our discussion] populating the Drug Runner world that mainly serve as obstacles. For the most part, these characters are dependent on their vehicles and we see only their vehicles, never the characters themselves. In fact, the only class of characters that ever emerge from their vehicles to wander the game world on foot are the mob bosses. This, however, will happen very rarely during game play, namely during the last mission that a player takes on in order to complete a level. (Refer to the mission descriptions in section 8.2.4.)


    3. Classes
      1. Player

Joe Mojo is a small time criminal who starts out in the rank and file, running errands for the local mob bosses.


At the beginning of the game, Joe drives a green Hauler that has seen better days. It is boxy and heavy, following an aesthetic that has been readopted and abandoned yet again and is now not quite old enough to be retro. However, Joe is very attached to his old car, and doesn’t plan on ditching it for a newer model anytime soon. Any money that comes his way will be spent on upgrades instead, and possibly a new paint job. That is, unless he is persuaded to take over the vehicles of those he "inactivates".


Animation of the player’s vehicle will be minimal, probably restricted to the brake lights going on whenever the brakes are applied.

[dave's comment on animation and appearance: wheels? suspension?]


Dialogue will also probably be minimal. Joe may give Crazy Taxi-style admonishments to the people he picks up who aren’t getting into the car fast enough.


We will have to design the player’s vehicle in more detail than the other vehicles, paying attention mostly to how it looks from the rear and sides. This is because it will always be on screen, since the camera will always be directly behind it.


Sounds will be restricted to vehicle sounds like screeching tires and engine revs.


Joe is of course completely controlled by the player of the game. Interactions of the player’s vehicle with other vehicles in the world are described in other


      1. Mob Boss

Different mob bosses are present in the Drug Runner world, forming a hierarchy which is reflected in the game levels. Vinny Spumoni, Joe’s first employer, and Vinny’s boss, Kendall Play, are the only ones that Joe knows about for the time being.


Vinny drives a bright yellow Flasher that doesn’t quite live up to its name. It is a little smaller than Joe’s car, and has a higher top speed, making him tough to nab should Joe ever need to catch up with him. Kendall rides in a black Luxmousine that is not terribly fast, but big and solid enough to take a lot of damage.


Vinny himself is low enough on the ladder to enjoy tricking himself out like a gangster in those music videos from the turn of the last century. Bright, fall-off-the-ass baggy clothing and lots of fake gold chains are the look Vinny favours. Kendall, on the other hand, prefers the tasteful floor-length trenchcoats and huge shoulder pads of a more refined era.


Animation of the vehicles is again minimal. The boss characters will need to be animated (using billboarding; refer to section 10.4) once they get out of their cars, but we will probably restrict this to a very small number of billboards per animation in order to reduce complexity.


The boss vehicles will follow very simple and possibly random paths through the game world for most of a level. When the player finishes all missions on the level and begins to give chase to the boss vehicle, however, the boss should try to evade the player’s attack (especially after the first collision).


On any given level, the boss of that particular level will provide narration on the mission descriptions, which run when the player picks up missions. Second, the boss’s voice may be heard whenever a player is taking too long to complete a mission, in the form of snarling and hilariously rude reminders to hurry up. Third, the boss may react verbally to assaults on his vehicle and his person. Finally, the player’s rating at the end of a level will be delivered both on-screen and by the voice of the boss who


We will have to design each boss vehicle. We could reduce complexity by basing all of them on the same car, one that is nevertheless easily distinguishable from the other types of vehicles (it should look much different from a police car, for example, even without the flashing lights), adding more shiny chrome trim as necessary.


  • Sound

Beyond the dialogue requirements mentioned above, there will also be collision sounds made when a player manages to inflict damage on the boss vehicle.


The bosses and their vehicles do not interact much with the player during most of a game level, beyond perhaps being seen driving around. It is at the end of a level, when the player must first damage the boss’s vehicle and then run over the fleeing boss, that the boss’s position and actions really become important to the player.


Oddly enough, the police take no notice of boss vehicles, and vice versa.


      1. Police

The police vehicles provide an element of pursuit to the game.


Police vehicles will be big, heavy, boxy, and not terribly fast. The stereotypical blue-and-white designs will be used, complete with lights on the roof that start flashing when a police vehicle gives chase. There will be a varying number of them on a game level, depending on its difficulty.


Animation will be restricted to flashing brake lights and flashing sirens.


The AI for the police will be the most complicated. A police vehicle should give chase to the player if the player is within a certain radius of the police vehicle and also in its line of sight. Thus, if the player turns a corner, the police should not be able to follow (unless it was close enough).


The police vehicle’s sight range should vary according to the difficulty of the mission that the player has picked up. For example, it should be longer when the player is attempting to take a hostage, reflecting the fact that the police are on higher alert for the player’s vehicle.


Police dialogue will be restricted to snide comments when a player is caught, along of course with the request for bribes.


We will need to design one police vehicle; all police vehicles look the same, so this is sufficient.


  • Sound

Beyond the dialogue described above, and possible collision or screeching noises made when the vehicle rounds a sharp corner in pursuit, there should also be siren noises that start up when a player is being pursued and stop when the police vehicle loses the player’s tail.


As stated in the notes on police AI above, the police give chase to the player only if the player is within the police vehicle’s sight range and line of sight. When a police vehicle manages to tag the player, the player is forced to stop and pay a penalty. Refer to the appropriate game play section for details.


      1. Obstacle Vehicles

There are two kinds of obstacle vehicles: normal cars on the streets that move in very simple paths, and schoolbuses that sit at the curb, or in the middle of the street blocking traffic.


The normal cars will be simple and not flashy; the idea is that they do not detract too much attention from the more important vehicles or the rest of what is going on during the game. They should also be easily distinguishable from the other types of vehicles in the game (mostly due to their anonymity).


Schoolbuses will be big, of course, and grey instead of yellow; they will also have children staring out of the barred windows making faces at passing traffic.


There will be no animation of the obstacle vehicles, beyond perhaps flashing hazard lights on the schoolbuses.


The AI for the moving obstacle vehicles will be very simple, probably along the lines of taking a left or right turn at random when they reach the end of the street that they are currently on.


There will be no dialogue for the obstacle vehicles.


We will need to design one moving obstacle vehicle and the schoolbus with perhaps two or three accompanying children’s faces. This will be enough, as all schoolbuses will look same and all moving obstacle vehicles will look the same except that they may be different semi-drab colors.


  • Sound

There will be no sound associated with the obstacle vehicles, except perhaps the sound of screaming schoolchildren in the background.


The player may drive around and damage these obstacle vehicles as necessary, keeping in mind that damage will also be inflicted on the player’s vehicle.



  1. World / Environment / Levels
    1. Overview
    2. The game takes place in a futuristic urban city.

      [dave's comment: concentrate on one level, only outline for other levels needed]

    3. Structure & Scope
    4. The map of the city is a 20 by 20 grid. Various landscapes and objects will appear on each block.

    5. Flow
    6. Initially only half of the map will be available to the player. As the player completes enough missions to advance to the next level, the map will unlock and the whole map will be available to the player to explore.

    7. World Interaction
      1. Level 1
        1. Overview
        2. The map available for this level will be the city centre. City centre is a very busy region with many streets, intersection, and car. Many important buildings will be located in this part of the city.


          [Insert Map of city here]

        3. Objects
        4. Buildings of different size, shape, and colour will be placed side by side along the side of the roads. There will be cars parked along the road and there will be cars moving in the direction of the flow. Traffic lights at each intersection will control the movement of cars going in different directions. Lampposts will be placed along the road with certain distance apart to provide lighting during night-time.


          [Insert pictures of buildings, lampposts and traffic lights here]

        5. Characters
        6. Since this region is the heart of the city, police will patrol this area more frequently to reduce the criminal activities. There is a school located in this area, therefore school bus will occasionally appear taking children to school, home and field trips.

        7. Gameplay
        8. The player will have to drive in busy streets with cars blocking the way and traffic light limiting the player's freedom to pass intersections safely. The player also has to be very alert because of the high police encounter rate in this area.

        9. Art Requirements
        10. Buildings will be represented by large block with different textures attached to each surface. Lamp posts and parked cars are static objects. Traffic lights will need a texture switch during the transition of states.

        11. Sound

        There will be a background sound that compose of various elements: engine sound from moving car, people sound from pedestrian, sound from birds overhead and radio from other cars. When the police is in a pursuit, there will also be siren sound.

      2. Level 2
        1. Overview
        2. The whole map will be available to the player. New areas surrounding the city centre have been unlocked for the player to explore. There are new landscapes, such as mountain and highways, and new places, such as the park, the dock and the airport.

          [Insert whole map here]


        3. Objects
        4. There will be highway signs such as speed limit along the highway. Large advertising billboards and directional sign will also appear along the highway. Trees, chairs and statues will be placed at various locations inside the park. Boulders will occasionally appear on mountain roads. There will be new buildings such as airport terminal and pier.


          [Insert pictures of signs and chairs etc]

        5. Characters
        6. Highway patrols get a lot less funding than regular police, therefore they have a tendency to slack off, which means the chance of encounter is relatively low. Wild animals will jump in front of cars along the highways and mountain range. Falling and rolling boulders are common when driving in the mountain.

        7. Gameplay
        8. On the highway, the player can enjoy driving at high speed. In the mountains, the player can enjoy the excitement of fast pace downhill with shape turns. In both cases, the handling of the car is crucial. Different driving surfaces and different weather will have different impact on the performance of the car.

        9. Art Requirements
        10. The grass on the two sides of the highway and the rocks in the mountain can be created using textures with self-shading. Objects at the park are static and only require a model. Wild animals and boulders can be created using billboarding.

        11. Sound

    The background sound will mainly consist of wind whispers. Animal howls can sometime be heard. There will be a little wave sound near the dock and also tire squeaking when doing tight turns.


  2. Game Play
    1. Overview
    2. The four gameplay modes are described in the ‘game modes’ section. The following section will use each of these game modes to describe a typical game scenario, including control, AI, the scoring system, flow of the game, the HUD, car damage and mission types.

    3. Single Player Mission Mode
      1. Overview
      2. The parts described in 8.2 are similar to some areas of the multiplayer mode, so this will be most extensive. Multiplayer mode will simply describe the differences between single and multiplayer mode.

      3. Control
      4. The control scheme of the vehicle is very straightforward: there will be configurable buttons for acceleration and braking with no shifting. The vehicle of the future has only one gear, which can ‘morph’ as needed by the transmission. The feedback to the player will be sense of speed and the noise generated by the engine. Also, the vehicle will be able to steer left and right with buttons assigned to those functions as well. Only digital controls will be implemented and the physics of the car will be implemented in respect to the digital controller scheme. An additional action button will be necessary to pick up and drop some of the missions that require these actions.

      5. AI
      6. The single player mode will include four different AI controlled vehicles, those being vans, school busses, regular cars and police cars. The first three follow their daily deeds and do not react to the player’s car, unless the player hits them. In case of a hit, the player’s car takes damage, but so does the other vehicle. If the AI vehicles’ damage level reaches 100%, it explodes, which can have effect on the player’s damage as well.

        The police cars are different: if a police car spots the player during an illegal mission (yep, they’re all illegal!), then they will pursue the player. If a police car manages to catch up to the player, the player must stop and ‘pay’ a bribe to the police car, which will then leave the player alone for the rest of the level. But it costs money and time and should be avoided at any cost. The method by which the police searches for the car and their states of awareness will be described in much more detail in the technical design, but it should be mentioned, that the player must be able to escape. The extremes known to the design team are ‘midtown madness’, where the police is super smart and practically unbeatable due to x-ray vision, and ‘metal gear solid’ with almost blind and completely stupid enemies that suffer from extreme memory loss even after being shot in the leg. Both extremes nullify immersion.

      7. Missions
      8. The whole game is based around taking on missions and accomplishing them within the time limit given. Missions are graded on their color-coded difficulty level that can range from easy (green) over intermediate (yellow) to hard (red). Initially, there will be a set amount of missions available on the map, depending on the level currently played. A smaller map will naturally have a reduced set of missions. Currently, there are four different mission types, which can differ in difficulty level, depending on the distance from start to destination:


        Mission Name


        Pick up and deliver

        Grab a package of drugs or other illegal wares and drop them off at the destination point. This is the simple ‘fire and forget’ kind of mission, where the player must simply pass a checkpoint to ‘grab’ the package and then pass the destination checkpoint to drop it off. Distances may vary, so this mission can be either green or yellow

        Dump evidence

        The player must find a small package within a fixed radius from the start point of the mission and then drive it to a destination point, which must simply be driven over. The difficulty of this mission type lies in the search for the evidence to be dropped, as it is not precisely charted on the HUD. It therefore ranges between yellow and green.

        Pick up and drive criminals

        Go to the scene of the crime, stop the car to a full stop, pick up the criminals. Then drive them to their hideout and stop there again. The difficulty arises from the fact, that the player must bring the vehicle to a full stop at the origin and destination of the mission, losing valuable time in the process. Also, police activity will be by far higher than regular, which may result in increased car damage! Difficulty: yellow to red.



        Mission Name


        Take a mobile target hostage

        This mission type is definitely the most difficult mission on the list. First, the hostage must be found around the mission’s point of origin, then dropped off at a hideout point by bringing the car to a stop. On top of it all, the police will be on the lookout for the player’s car. Of course, this pays off in the highest amount of cash.



        Additionally there will be the boss level after all missions in the current level are completed. In the boss level, the player has a fixed time to reach the destination of the boss’s car (marked on the HUD) and force the boss to get out of the car by hitting the boss vehicle often enough. When the boss is forced to leave his car he can be run over with a loud -splat!- to finish the level, gain a new, faster, more robust car and unlock a new part of the city. In more advanced levels, some of the above missions may be combined to form a single, long mission, which is paid very well, but not before all mission parts are accomplished.

      9. Scoring
      10. Scoring is based on difficulty of mission, time taken to accomplish the mission, and damage to the car taken, as it is automatically repaired to 0% damage at completion of a mission. Scoring is split into time, money, car damage and police capture. The scoring in more detail:




        Scoring Topic



        The timer is initially set to 15 seconds. This is the time the player has to pick up the first mission and stock up on time. Depending on the difficulty level, the players time counter is added 20, 30 or 40 seconds. This is the time granted to accomplish the mission. Once a mission is successfully completed, the player is given an extra 15 seconds to search for the next mission. All given time is accumulated, so the more skillful player can gather much time to go after the really hard missions.


        Cash is given to the player upon completion of a mission. After the player takes on a mission, a cash award is displayed in the HUD, gradually counting down as time progresses. The initial sum of money in the HUD is based on the difficulty of the mission: green = 10000$, yellow = 15000$ and red = 20000$. Every second the game progresses, the money counter looses 100$. When the mission is successful, the remaining amount of money is transferred to the player’s permanent account.



        Scoring Topic



        During missions, the player’s car can take on heavy damage leading to a reduction in top speed and also reduced grip. The damage level of the car is 0% initially, but increases depending on the collision events that have taken place during the mission. A more detailed description can be found in the ‘health’ sub-section.

        Police capture

        As mentioned in the AI section, if a police car in pursuit ‘tags’ the players car, the player will be forced to stop, loose 5 seconds on the timer and pay a 2000$ bribe to the police. The bribed police car will not bother the player during the complete level after being bribed. Depending on the level of play there will be between 2 and 5 police cars patrolling the city (visible on the HUD). If the player can not come up with the money, then for each missing 500$ of the bribe, 1 second is removed off the time counter.



        The values mentioned in this section are all preliminary and will be set in a separate file or in a special developer mode, so the game designers can tweak these parameters during testing of the game. Balance is the key word here. Also, level design must be tuned toward these parameters, especially the size. This again depends on the top speed and handling of the vehicle. It is very obvious that this part of the game will need to be extensively play tested.

      11. Flow
      12. The player starts on a fixed spot in the level, with no cash, 15 seconds on the timer and in no motion. The camera zooms in on the player’s vehicle, while the level boss counts down from three (or some other voiceover, to be discussed). Once the zoom is completed, the game starts! With respect to the missions described above, the game runs in a frantic pace, only forcing the vehicle to stop when the mission requires it or the player gets tagged by the cops. The sequence in which the player tries to accomplish the missions is crucial to his/her overall success and might be determined by the time left, the difficulty of the mission, the position of the police cars and the vehicle’s damage level. If the player succeeds in accomplishing all missions in a single level, the boss’ car appears as a big orange dot on the HUD. The player must then locate and destroy the boss’ car within 40 seconds. During this time the boss uses all foul language know to man to stop the player from harassing him, which of course has no effect, as it is the players goal to kick his ass out of this district so the player him/herself can take over. Once the boss’ car is destroyed, the boss gets out of the car, screaming and swearing (billboarded sprite with little animation, see graphics/animation sections). The player then can simply run over the boss to finish the level and gain cash and other nifty awards such as a newer, faster car and a completely new area of the city, which is merged with the known universe to make up for a larger playfield in the following levels of gameplay. After the scoring is done and the melody of victory is played, the camera pans away, the screen fades out and the next level of gameplay starts exactly like the first one.

      13. HUD
      14. This is an important element of gameplay, as it supplies the player with almost all-important geographical information on the game world. It must be alpha transparent so the action in the background is visible to the player and at the same time be non-obtrusive. This makes it clear, that the HUD will be placed towards one of the four corners of the screen. As the map is a grid, the HUD will display the district in which the game is played in a static manner (tech: orthogonal projection of simple quads and points, with points being updated according to their position in the world. no transforms). The missions and their respective destination points are displayed as colored dots, coded in their difficulty levels. The police cars are coded as blue squares. These encodings vary slightly in multiplayer (see ‘multiplayer’ subsection).

      15. Health

      The damage level of the vehicle is initially 0%. Depending on the object with which the player collides, the damage

      level increases according to the table below.



      Collided Object

      Damage Increase



      Other Object (i.e. lamppost)




      Exploding Vehicle (due to 100% damage of AI vehicle involved in collision)




      Every 1% of damage taken reduces the top speed of the car by 0.25%. Additionally, grip might be influenced. If the damage level reaches 100%, the players car is destroyed and the game ends. At completion of a mission, the vehicle is automatically repaired to 0% damage level, or until all money is depleted. Repairing 1% of damage will cost the player 10$. This amount is deducted off the player’s permanent account directly after the boss paid him/her off for the last mission. Damage, which can not be covered by the player account persists and is taken along to the next mission.

      The AI vehicles all start off with a certain (random) level of damage, so the player can not necessarily know, which cars will explode on impact.

    4. Multi Player Mission Mode
      1. Overview
      2. As mentioned above, many parts of the single player experience also apply to this game mode, so the following will only describe differences and additions/deletions between the two modes.

      3. Control
      4. The control scheme is identical to the single player mode. Only small change is that the action button can also be used to activate a power up, of which only one at a time can be possessed by each player.

      5. AI
      6. The only notable difference in AI behavior is that the police cars lock on to whoever’s car they spot first. Once the ‘lock’ is removed again (due to the locked player escaping the ‘lock’) the police goes back to ‘awareness state’, locking on to either player again.

      7. Missions
      8. Same as in the single player experience.

      9. Scoring
      10. Scoring is somewhat different, as there is no time limit set to the game. The frantic pace of the multiplayer game emerges from the race against each other, to get the best paying jobs and complete them as fast as possible. All scoring schemes set up in single player mode are the same in multiplayer mode, with the difference, that certain power ups can turn the tides of battle quite drastically. See the ‘power ups’ subsection below.

      11. Flow
      12. The game is played on a vertically split screen with only one central HUD map for both players to use. This map is likely to be placed in the center of the screen in the top area. Both players are randomly placed in the city with no clue as to where they are starting. The map offers 2-3 missions of each difficulty level to give the game a good balance. When all missions on the map are accomplished, the game ends and the player with the greater amount of cash wins. The front end of the game (menus) must support multiplayer selection and offer various vehicles and maps depending on the unlocked maps/vehicles in single player mission mode. New assets in the multiplayer mission mode are the power ups, which are presented in more detail below.

      13. HUD
      14. The HUD map is shared in this game mode, to reduce clutter on the screen, one more reason why it is static, displaying the entire game world. Color codings are similar to single player mode, yet differ in some aspects: The mission destinations are color coded to the player who is trying to accomplish them, and each player is depicted by a big colorful glowing circle on the HUD.

      15. Health
      16. The players damage level is just as critical in multiplayer mode as it is in single player mode. Repairs are also handled identical.

      17. Power Ups

      This is the only real addition to the multiplayer mode. In some streets, the players will find power ups lying on the ground, which can be picked up by driving over them. Any player can hold only one power up at a time. To activate the power up, the player must press the action button. Here is the table of possible power ups:


      Power Up


      Gas Tank

      When activated, the player’s top speed increases by 30% for 4 seconds. This results in less control over turns and braking, so it should be used on straight paths with only little traffic. But careful: if the player is going less than 60 km/h, the gas tank explodes instead of being picked up! So be fast!

      ‘Steal’ Object

      When activated, the player must simply touch the other player’s car to ‘steal’ the mission from him/her. The power up is active for 5 seconds after activating it.

      Damage ‘Object’

      When activated, the player inflicts 30% of damage to everything he/she hits, including AI controlled cars, so take it careful! Lasts for 5 seconds after being activated

      Money Bag

      Simple. It just stocks up on your cash. Even number of moneybags distributed throughout the city to keep things even.


      An important aspect of the game: If there are still jobs available and the player is out of a job for more than 20 seconds, his/her cash is gradually reduced by 50$ per second, as the boss doesn’t like fights or laziness! This is to prevent one player from ‘only’ fighting the other player (at least in this mode).

      The power ups are not visible on the HUD map and are placed at random, so the player must find them during the game. This should introduce some interesting decisions and tradeoffs in the multiplayer game.

    5. Single Player Time Trial
      1. Overview
      2. Depending on the unlocked areas in the single player mode, there will be time trial paths through the city, which can be selected, in the menu front end.

      3. Control
      4. As described above

      5. AI
      6. In this mode, there will be AI controlled cars, both as obstacles and police cars. The goal of the police cars is to reach the goal in minimal time, just as it is the player’s goal. Additionally, the police cars will react aggressively to the player trying to pass them and will try to push the player into other vehicles and buildings.

      7. Scoring
      8. The sole purpose of this mode is to reach the goal after three laps in the fastest time possible and also the best race position possible as the police cars are also trying to win. Best times are kept in a persistent high score list.


      9. Flow
      10. The player starts at the goal/finish line and a timer counts down from 3 (boss voiceover). The race proceeds as mentioned above, with the damage level of the player rising as more collisions occur. The game ends after three laps are completed or the damage level of the car reaches 100% leading to the often-mentioned explosion.

      11. Health (and Replenishment)

      Damage levels are the same as in single player mission mode, but as there are no missions, the player can pick up gas tanks as in multiplayer mission mode. These gas tanks not only speed up the car for 4 seconds, but also reduce the car damage level by 25%.

    6. Multi Player Time Trial Mode
      1. Overview and differences to Single Player Time Trial Mode

    The multiplayer time trial mode is mostly similar to the single player version, only that the front end must allow to switch police opponents on or off (as the scores are not tracked in the persistent high score list), and that some power ups exist on the track selected. These are listed in the multiplayer mission mode. Only the Damage Object and the Gas Tank of the multiplayer mission mode will make it into the multiplayer time trial mode (as the other two wouldn’t make much sense).


  3. Rewards
    1. Overview
    2. Rewards in the Game are based on completion of levels in the single player mission mode. Every time the player finishes a mission, he/she is rewarded with new assets as described below.

    3. Unlockables
    4. Each level, which the player can successfully finish, gives way to a new part of the city map. These new explorable parts add game play to all modes of the game. In single and multi player mission mode, the player/s has/have a larger city to explore with more intricate mission structures. Also, tracks are added to the time trial modes.

    5. Collectibles
    6. The player starts off with a rather slow and not very stylish vehicle. As he/she unlocks levels, new vehicles with higher top speeds, better handling and much better visuals are unlocked. These are then also available in the time trial modes and can (and must) be used in the higher levels of mission gameplay.

    7. Feedback (Sounds and VFX)
    8. Accomplishing a mission or even a level will be gratified by the level boss (or oneself after killing off the boss) by voiceovers, which mal vary depending on the time taken for the mission. If missions are completed in time, the boss will praise the accomplishment. A slew of ‘eye candy’ will be implemented in the game to let the player know what’s going on (See section ‘graphics/FX’ for more details).

    9. Easter Eggs

    When all levels of the game are finished (we are currently aiming for two levels), The map will be populated by billboard versions of the six group members, which must all be driven over in 60 seconds! Any grief of the player towards poor design or other visual flaws can be lived out at this point. Our counterparts will run through the streets screaming and begging for their life! But reaching this spot will be very, very hard!

    [dave's comment: fun!]



  4. Graphics / FX
    1. Overview
    2. The rendering engine will have many tasks to do to achieve the visual style we strive for. There are many detailed issues to the renderer, but the following section will describe in more detail the key visual concepts of the rendering engine. The technical details will be described in much greater detail (and optimized) in the technical design document.


      The special graphics effects that will be employed in Drug Runner can be broken down into four broad categories: Shading effects, Particle system effects for smoke and sparks, bill boarding effects for boss models and decal effects for persistent changes to the universe.


    3. Cartoon Shading
    4. The predominant visual style in the game is best described as a ‘gritty, futuristic comic like setting’, much like it is known from popular comics such as ‘Batman’. The rendering of this world will therefore use much surface coloring, instead of excessive use of textures. Textures will mainly be used to animate surfaces on various vehicles and where cartoon shading does not achieve the desired effect. Otherwise, the world will consist mostly of streets and buildings, which are rendered using one-dimensional (color) textures and rendering the corners of all objects with thick black lines, mimicking the ink of the cartoon artist. If this cannot be achieved dynamically, which will be our first attempt, then static world objects will be designed in a comic style, only using dynamic cel shading on the vehicles and other dynamic objects. A more technical description will be available in the technical design document. There are many resource on the web, especially on gamasutra.com, which describe in great detail the technique of cartoon rendering.

      [dave's comment: note that cartoon textures may work just as well]

    5. Particle System
    6. The particle system will be used to support all special effects and the physics system. The table gives a brief description of all the areas in which various derivatives of the base particle system will be used.




      Use of Particles


      The entire explosion will consist of glowing particles. Additionally, if the object exploding is a vehicle (which is very likely), then the particle system can also be used to simulate flying debris after the explosion occurred


      As a side effect of the explosion, a cloud of smoke will arise from the center of the crash and also from all flying debris.

      Exhaust Smoke (Car Damage)

      Instead of geometry deformation, we will give visual feedback to the player through varying amounts of smoke and sparks exiting the vehicle’s exhaust pipes.


      When the players vehicle collides with a building or another vehicle, there will be sparks flying, with a different visual style depending on the object hit.


      To support the dark, sinister style of the game, it will be possible to make it rain in secluded areas of the map.

      Physics System

      To simulate proper car handling and suspension, the particle system will be expanded to handle springs and interconnections between particles. This will be used to independently control the force on all tires of the vehicle

      Atmospheric Effects

      Such as burning trashcans, broken lampposts, and busted phone booths (this is all optional and depends strongly on the time we have)


    7. Billboarding

      A billboard effect is an image or texture placed onto a flat surface whose normal always points towards the camera, regardless of whatever is going on in the rest of the universe. The image displayed to the camera is always "face-on". Unlike a regular model therefore, a billboard only requires the graphics system to consider one side, thus significantly reducing computation time and coding, at the cost of eliminating the 3 dimensional "feel" to the model.



      Notice how in this figure how the "boss" will always be facing the car as it passes by.



      In drug-runner, there will be "bosses", which will be complex looking, humanistic characters. To display such a complex object, this billboarding technique will be used.


      In addition the contents of the billboard will change slightly over time (perhaps two frames only), to simulate "animation".


    9. Decal System


Decals are used to show pot marks, burns, blood, foot prints, and sometimes insignia and such on walls and floors. In most cases this is done by having a polygon sitting just above or just in front of the wall or floor to give the illusion that the blood stain or bullet hole is actually on that surface. Of course the decal is clipped to fit on the surface on which it is placed so that it does not hang out over the edge and look funny.

In Drug Runner, decals will be employed to implement the following effects:




  1. Animation
    1. Overview
    2. The Game will not be very ‘animated’ in that sense as the timeframe offered to develop the art assets simply doesn’t exist. Yet, there will be some small areas of animation, which are described below.

    3. Classes
      1. Characters
      2. Some of the gameplay elements require human beings to be populating the streets of our virtual city. Especially the hostage missions the ‘kill the level boss’ parts and – not to forget – the ‘Easter egg’ part where the designers must be killed. The animations will be simply animated textures on billboards. The texture style will be consistent with the rest of the world in a cartoon rendered way. There will only be a few frames [dave's comment: this may be larger than you think] of animation to each character, as this will enhance the comic/retro look of the game.

      3. Objects

    The vehicles, especially the busses, will have animated textures, to give the impression of the vehicles being full of people, afraid of all the havoc going on in this dark futuristic world. Most time will be invested in getting some flashy animation’s going on the players’ vehicle. Other textural animations will include the flashing lights of police cars in ‘alert state’.


  2. Camera
    1. Overview
    2. The game camera will be mostly fixed behind the player in the first iteration, but to reduce ‘jerkiness’, the team will

      Try to enhance the visual appearance in a second iteration involving a constrained quaternion rotation to the joint between the player and the camera.

    3. Gameplay Cameras

    The complete game will played from a 3rd person point of view to enhance the overview of the game and make for a more arcade like experience. The player will be able to select from 3 different camera positions: close-up, normal and far. It will be able to set this in the front-end menu (default), but will also be adjustable on the fly during the game (extra button necessary). As the game will work with back face culling activated on all solid objects, the camera can simply pass through them, not having to worry about collision with world objects. If the world would consist of transparent objects, this would be an issue (-> hasn’t been thoroughly discussed yet).

  3. Sound
    1. Overview
    2. The overall style of audio used in the game is going to be dark and mysterious to match the context of Drug Runner. However, there will still be an option in the game for the player to choose the style of audio he/she prefers to be used.


    3. Characters
    4. Only some characters will require sound implementation. They include the boss who will give the mission commands, cops who are chasing after the player, voices coming out of other cars which are hit by the player, and voices from the debriefing screens (e.g. 'congratulations' screen, 'try-again' screen). Also, narration is provided at the beginning and end of missions.


    5. Ambient
    6. There will be an ambient sound effect layer. As the player passes over certain districts on the city map, that terrain type's ambient sound loop begins to play. As the player passes over a second district type, the first ambient track gently fades out while the second fades in. There will be no more than two ambient sound effects cross-fading into one another at a time.


    7. Music
    8. Music is split among 4 categories: 1) Setup mode, 2) Mission panel, 3) In-game music, and 4) win/lose music.

      In-game music responds to the state of affairs the player is experiencing . In other words, music in the game will respond to the state of the game, i.e., what's going on. Music for non-interactive parts of the game will depend on the player’s preference for style of music used in the game.


    9. Front-end
    10. The player can choose the style of sound used for the front end. Each style has a template of sounds which are used when events are invoked. Most of the sounds used for the front-end will be ambient. They are there to create the appropriate atmosphere for the game, such as engaging the player into starting the game, or bringing the player to the next level.

    11. FX

    There will be a 3D sound engine, complete with a parameter list defining each sound's path, traveling speed, special effects, and so on. The goal here is to have in-game dependent sounds, as the game itself is 3D. Real time Doppler engine will be implemented. Also, the special effects will provide "enhancement" to the gaming experience, further immersing the player in a dark and mysterious setting. Action sounds include car explosions, car collisions, and human screeching screams.

  4. Tunable Parameters
    1. Overview
    2. There are some variables that the programmer can change to modify the attributes and behaviours of different objects in the game.

    3. Character Attributes
    4. Various parameters for the car such as top speed and acceleration are tuneable to alter the performance of the vehicle.


      The distance that a police car can see is a tuneable parameter that will alter the difficulty of the game.

    5. World Attributes
    6. The current weather such as sunny or rainy is tuneable to give different driving conditions.


      The frequency of traffic lights change is tuneable to give different difficulty when passing an intersection.

    7. Object Attributes

    The size and location of objects are tuneable parameters.


  5. Additional Features
  6. This section is pending. Will be added in later versions of the document.


  7. Risks / Problems / Concerns

The design team is aware of the scope of the game and has planned all modes separately, so that parts can be left out, if time problems arise. The core part of the game is the single player mission mode with the cartoon rendering, the physics system for the vehicle and some special effects such as decals and particles (and of course the mission based structure). Once these parts are all accomplished, the other aspects can be tackled.