1 Introduction
1.1
Objective
The objective of this report is to create a creative and interesting
application for the tabletop computing environment. In this project, it was
decided that a game named ‘Bananas’ would be developed.
1.2
Scope
The game will include the entire implementation of the game from the
idea generation, scenario design, making scenes to testing.
1.3
Methodology
The game will be developed with the Torque Game Builder, multi-touch
tabletop in the Interactive Multimedia lab and various other softwares such as
Gimp and Notepad++.
2 Background
Human–computer
interaction (HCI) is the study of interaction between human(users) and computers.
The rapid growth of computing has made
effective human-computer interaction essential. It is important for the growing
number of computer users whose professional schedules do not allow elaborate
training and experience that was once necessary to take advantage of computing.
Increased attention to usability is also driven by competitive pressures for
greater productivity, the need to reduce frustration, and to reduce overhead
costs such as user training. As computing affects more aspects of our lives,
the need for usable systems becomes even more important.
Multi-touch and tabletop are the most popular areas of interest in
HCI. They have been creatively combined to form the multi-touch tabletop. It
has become a very active area of research and countless number of applications
has been developed for them. Multi-touch
tabletop involves the input technology using hands and gestures are the most
intuitive tools for human. Thus, this technology becomes a core component of
the information devices adopting dynamic touch interfaces.
The success of this technology can be seen from the success of Microsoft
tabletop, iPhone and tabulaTouch.
3 Overview of
Entire Game
There are various types of games that can be developed for the
multi-touch tabletop. They are role-playing, tile-based, board, card, dice,
miniature and paper & pencil.
After much consideration, role-playing games was chosen. This is the
result of the role-playing games genre gaining popularity among people of all
walks of life.
After doing some research and having countless group discussions, we
decided to base our game on the popular game ‘Worms’. The idea of creating a
bright and cartoon-styled animation with a arsenal of weapons caught the
group’s attention.
We then decided to create a two-player game where the objective is to
defeat the other player with their individual arsenal of weapons. The players’
movements are restricted to a certain region of the tabletop.
In the arsenal of weapons, there is a super weapon which inflicts the
most single damage. The other weapons can only inflict lower amount of damage.
We did a verbal survey and the general consensus seemed to be the monkey
and the jungle theme. So we decided the monkey to be our avatar and have a
jungle-themed background.
4 System Block
Diagrams
The following show the overall and specific block diagrams of the
game:
Overall System Block Diagram
Block
Diagram of Weapons
5 Novelties
The game is visually pleasing as the graphics design has taken into
consideration what would make any player unknowingly attracted to the game at
first sight. This is partially due to the cartoon-styled animations. Once the
player starts playing the game, he will find that it very intuitive and
user-friendly. A certain amount of realism has also been embedded into the game
such the splash of blood when the monkey is hit. Moreover, the learning curve
is gentle and thus the player can get hang of the game very easily. The
following explains further the novelties of the game in detail:
Monkey Movement: This functionality
allows the player to capitalize on the affordance of a touch interface. The
movement is very intuitive and natural as it just requires the user to drag the
monkey from one place to another.
BomBanana: It makes the the game incredibly fun by
increasing the difficulty by its homing capability. Thus, it gives the players
opportunity of having bragging rights if he/she is able to evade the homing
banana. The special feature about the bombanana is that the spawned bananas
which appear from the trees and home to the player.
Grenade and Cannon: Both these weapons are unique from the rest in
the sense that both are projectiles. Since the game is being played in a 2D
top-down view, it is impossible to implement actual projectile motion. As such,
by varying the size of the grenade and cannon ball, we were able to visually
simulate projectile motion. In addition, both these weapons have a ‘powerbar’
feature which allows the user to fire at the opponent with varying speed. The ‘powerbar’
appears as the user holds down the ‘fire’ button indicating the speed of the
projectile.
Bow/Arrow and Machine Gun: The firing rate is controlled by having a
delay between each shot which makes the game more challenging. It is unlike
other games where the firing rate is unlimited.
Monkey Copter: There is a trackpad
control implementation which makes use of the affordances of multi-touch
interface. The movement is made much more intuitive as opposed to buttons to
make it go up, down, left or right.
Console/Ammo: We have added two
functionalities into one interface in the console area. The icon which shows
the remaining ammo is also used to enable the player to alternate between
arsenals of weapons available to the players.
Crates:
Although this concept has been applied before and is evident in other
games, we felt it would be very much suitable to Bananas. We took it one step
further by introducing super weapons such as the bombanana and the monkey
copter which can have either ammo replenished, or activated by the crate
respectively.
6 Technical Challenges
One key difficulty in developing a multi-touch game is integrating
everything together. Since there are so many objects that respond to touch,
ensuring that the right event is triggered for the appropriate gesture by the
player is crucial. Therefore, we had to do several rounds of testing to ensure
that the player experience is not pre-flawed. There were also specific
technical challenges with the regards to the other components of the game.
Monkey Movement: It was difficult from
the player’s experience point of view. There was difficulty in determining
whether the player had actually touched the monkey sprite and dragged it
correctly so that it will move (touching outside the monkey will not allow it
to move). Thus to overcome this issue, we made use of red and green sensor
images that allow the player to know if they have got it right. A green sensor
means they can move the monkey while the red means otherwise. This made a world
of difference and players were able to adapt to the controls much faster. Sound
effects of the monkey were also added and this helped too. Another difficulty
was to limit the monkeys from going over the river. This was solved by using an
underlying terrain which can respond to touch events. That terrain was set to a
size appropriately such that it does not cross over the river. This also prevents players from controlling
the other player’s monkey.
BomBanana: The scripting of the Homing
portion of the banana efficiently so that it doesn’t take up too much
computation. It was also required for the balancing of the algorithm so that it
is indeed possible to evade the homing bananas.
Grenade and Cannon: Both these weapons simulate projectile motion
as mentioned in the novelties section above. Due to inadequate features
available in TGB, we had to vary the size of the projectile based on the
distance it will travel which in turn is determined by the duration of hold of
the ‘fire’ button. Due to some math and geometry calculations, the coding
eventually turned out to be very complicated. Another difficulty that arose
from this was that the projectile had to ‘pass over’ the opponent if the power
is too large. This had to be done while detecting collision and determining if
the projectile has travelled the correct distance based on the initial speed
and power. Once again, the math proved to be a big hurdle that we had to
overcome.
Monkey Copter: This weapon required a
whole new approach to code the implementation. The main challenge was changing
the control buttons to track pad since we have to change from 4 buttons that
perform four individual tasks instead of a single button which can do all four.
7 Conclusions
The outcome of the project has been very good based on the feedback from
people who played the game. However, there are various aspects of the game that
can be improved:
·
Having an
option of allowing more than two players. But there is a limitation of how many
players can play at one time due to the limitation of action area for each
player.
·
Introduction
of computer-controlled avatars which randomly aid or attack the players. Thus
would make the gameplay more interesting.
·
There
should be a beginner and advanced play mode for the game to be playable among
all age groups.
The principle aim of HCI is to improve interactions between users and computers
by making computers more usable and receptive to the users’ needs. The ultimate
outcome of HCI should be to eventually minimize the barrier between human’s
cognitive model of what they want to accomplish and the computer’s
understanding of the users’ task. From the experience of using multi-touch
tabletop, it is believed that the principle aim is nearer and the outcome is
definitely achievable.
Although considerable amount of time and effort
has been put into the project, the group feels that it was worth it. The group
has gained a huge wealth of skills and knowledge. The group looks forward to
further exploration into digital media technologies and definitely recommends
the module to be offered to future students.
Appendix
Screenshots
General Game View
General Game View with
Labels
Links
Blog:
http://bananas-ultimatemultitouchgame.blogspot.com
PowerPoint
Webpage
Game Run Instructions
Source Codes:
Game Scripts
Game Behaviors
OR
Bananas Beta 1.0 (or
Other)\game\game\gameScripts
Bananas Beta 1.0 (or
Other)\game\game\behaviours
Contacts:
•
Ritesh Angural ritesh@nus.edu.sg
•
Murtaza Shabbir Kurbanhusen u0705949@nus.edu.sg
•
Joshua Lurdes Newman joshua_newman@nus.edu.sg
•
Sean Yeo Weiliang u0705860@nus.edu.sg
References
[1] Human Computer Interaction: Introduction and
Overview. (n.d.). Retrieved March 6, 2010, from
http://www.sigchi.org/chi97/proceedings/tutorial/rjkj.htm
[2] Implementation of
Multi-touch Tabletop Display for HCI (Human Computer Interaction). (2007). Retrieved March 1, 2010, from http://www.springerlink.com/content/ank44350j6t56384/fulltext.pdf?page=1
[3] Jacko, Julie A., & Sears, Andrew. (2008). The Human-Computer
Interaction Handbook : Fundamentals, Evolving Technologies, and Emerging
Applications (2nd ed.). New York: Lawrence Erlbaum Associates
