Marble Platformer Prototype - GDD

2020

PROTOTYPE 1

MOMENTUM BASED 3D PLATFORMER

BILLY KANE – K013157I

High Concept....................................................................................................................................... 2
Player Character.................................................................................................................................. 3

Controls........................................................................................................................................... 3
Keyboard ..................................................................................................................................... 3
Controller .................................................................................................................................... 3

Mechanics ....................................................................................................................................... 4
Movement................................................................................................................................... 4
Jump............................................................................................................................................ 5
Camera........................................................................................................................................ 5
Saving & Respawn....................................................................................................................... 6
Colour Change............................................................................................................................. 6

Platforming Elements.......................................................................................................................... 7
Platforms......................................................................................................................................... 7
Control Point Platform ................................................................................................................ 7
Spline Platform............................................................................................................................ 7
Spinning Platform........................................................................................................................ 8
See-Saw Platform........................................................................................................................ 9
Bridge .............................................................................................................................................. 9
Button Bridge Puzzle.................................................................................................................10
Ramps........................................................................................................................................ 10
Loop............................................................................................................................................... 11
Teleport......................................................................................................................................... 11
Water ............................................................................................................................................12

Game Conditions...............................................................................................................................12
Collectables ................................................................................................................................... 12
Win State.......................................................................................................................................12

Level Maps ........................................................................................................................................13
Map ...............................................................................................................................................13
Collectables ............................................................................................................................... 13
Map - Path.....................................................................................................................................14
Beginning Area ..........................................................................................................................14
Main Area..................................................................................................................................14
Map - Measurements....................................................................................................................15
Map - Height .................................................................................................................................16
Map - Notes ..................................................................................................................................17

1

High Concept

Prototype 1 is a momentum-based 3D physics-based marble platformer focused on maximizing
character acceleration and physics challenges. Momentum and physics-based systems in games are

fun and challenging, with an air of unpredictability that is largely missing from most platformers.
The primary inspiration for this prototype are the Sonic franchise and Marble Blast Ultra. They use

speed to provide both challenge and fun, giving a sense of exhilaration at high-speeds while
requiring precision movement and slower speeds to solve challenges. It is an extremely fun and
challenging mechanic when balanced well. Levels must account for players who lack the skills to gain
a lot of momentum while also acknowledging some may speed through and gain incredible speed
and air. Levels must also encourage slower, methodical physics-based challenges without draining

the fun players get whilst rolling around.
The game, to distinguish itself from its peers and provide a refreshing platforming experience will
take the concepts of similar momentum physics platformers and translate it into a large, open map
encouraging exploration and giving players the freedom to play around with marble mechanics in a

sandbox environment.

2

Player Character

Controls
Keyboard

WASD – Move Forward/Left/Down/Right
R – Respawn
Escape – Pause

Spacebar – Jump
Mouse – Move Camera

Controller

LA – Move Forward/Left/Down/Right
X or Y – Respawn
Start – Pause
A or B – Jump
RA – Move Camera

3

Mechanics
Movement
Players can move the marble using the WASD keys or the L-Analog Stick. The marble (player pawn,
spherical physics object) is then pushed in the direction of the input using force, causing the marble
to roll. Force is calculated by getting camera vector and applying force (=vector*1000).

If an input different to the current rolling direction of the marble is inputted, then the force will push
against the momentum of the marble. This means at higher speed the marble turns slower and takes
longer to break to stop. Using an input opposite to the current roll of the marble will help reduce its

speed.

4

Jump
Pressing the Spacebar or A/B buttons will make the marble jump. The player cannot control the
movement of the marble whilst it is in the air be it from jumping or being launched by momentum.

The max height of the jump is 300 Unreal Units.

Camera
The player camera can be controlled using the Mouse or R-Analog stick. The marble is always
centred and 1/3rd of the screen height, allowing the player to see more of the level and less of the
ground. As players speed up, the camera zooms out, however the marbles position on screen will

remain the same.

5

Saving & Respawn
Players can use the Save locations to automatically save progress when entering its vicinity. When

the marble dies, it will respawn beside the save location column.

Colour Change
Players will be given a variety of colour options for their marble which can be changed by rolling on

to buttons at the beginning of the level.

6

Platforming Elements

Platforms
There are a variety of moving platforms that are used to build puzzles and provide different

challenges to the player.
Control Point Platform

A simple platform that moves from point A to point B then point B to A on loop (ping-pong).

Spline Platform
Allows more diverse movement than the Control Point platform. Platforms can move to an unlimited
number of points. Platforms can move from on a First Point>Last Point>First Point loop similarly to

the Control Point Platform.

7

Platforms can also move on a First Point>First Point loop, but only if First and Final Points are the
same location, allowing continuous movement in a closed circuit.

Spinning Platform
The Spinning platform will rotate continuously on its central pivot point. Alternate shapes can be

used to provide unique challenges.

8

See-Saw Platform
The See-Saw platform will be a physics-based platform that will react to the marbles weight, bending

on its pivot. When the platform has no weight applied it will return to its original flat positioning.

Bridge
Bridges will be used to connect separate parts of the map. They will react to the marbles weight

using the engines physics, akin to a rope bridge.

9

Button Bridge Puzzle
Button bridges will remain hidden beneath water, rising when the associated button is pressed to

allow players to reach previously unreachable areas.

Ramps
Ramps can be used to launch players who are traveling at high speed. The steeper the incline the
faster the marble must travel to climb it, and speed gained beyond the amount needed to scale it

will provide added momentum to the launch.

10

Loop
At super high speeds, the marble can travel 360-degrees in a looping ramp.

Teleport
When the player passes through the Teleport, they will be transported to a predetermined location

on the map.

11

Water
Water is the only hazard the player will encounter, killing the marble instantly when touched.

Game Conditions

Collectables
The player must collect all collectables in the level to complete the game.

Win State
Once all collectables are gathered, the player unlocks new abilities.

Jump Height During Game Post-Game
Water Hazard 300 Unreal Units 600 Unreal Units
Deadly Non-Deadly

12

Level Maps

Map
The map is split into 2 areas, the beginning area on the right where players will get used to and learn

controls and the main area where players have more freedom to explore.
Collectables

There are 19 collectables in the map.
Players must collect all 19 to complete the level.

13

Map - Path
Beginning Area
The path here is linear and simple, providing basic challenges to aid the player in getting used to
mechanics and show them what is required to complete the level.

Main Area
Players are given more freedom in the main area of the map, with 4 distinct path splits towards

different challenges and collectables.

14

Map - Measurements
The map will be a huge 130000x9000 Unreal Units compared to the players size of 100 Unreal Units.
This space allows players to make the most of rolling at high speeds, something a smaller map would

not allow.

15

Map - Height
This map shows the height of the level, which is also huge, peaking at 20000 Unreal Units (again

compared to the Marble’s 100u). This allows for larger ramps for accelerating speed.

16

Map - Notes
Here are some additional notes detailing information about moving platforms and puzzles.

17

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