University of Derby, 
               Department of Computing and Mathematics 
                 Mediterranean College of Thessaloniki 
                             
                             
           Design Patterns For Implementing 
                   Game Mechanics 
          
          
          
          
                             
         Author:                                                    Supervisor: 
         Xeni-Christina Kounoukla                      Dr. Apostolos Ampatzoglou 
                             
                             
          
                      Thessaloniki, May 2016 
                       Abstract 
        Typically, developing computer games is a very complicated task and as a result, 
        many games suffer from poor design and weakened software quality attributes like 
        maintainability. On the other hand, according to the software engineering literature, 
        the application of GoF design patterns in game development is beneficial concerning 
        certain design-time qualities. The aim of this study is to introduce basic instantiations 
        of game mechanics through GoF patterns and evaluate the benefits of this mapping. 
        Having specified  implementations  on  how to  instantiate  a  game  design  pattern  is 
        expected to increase their usability in practice. Nine mappings were identified and a 
        case study on open source software Java games was performed in order to explore the 
        applicability  of  the  approach  and  evaluate  the  resulting  benefits.  Additionally, 
        alternative, non-pattern employing implementations were developed, in order to be 
        directly compared to the GoF pattern involving instances regarding software quality. 
        The  findings  suggest  that  the  application  of  GoF  design  patterns  in  the 
        implementation  of  game  mechanics  improves  certain  aspects  of  software  quality, 
        while it might, one the other hand, weaken some other. Therefore, it is necessary for a 
        designer to consider several factors, such as the most desired quality attributes and 
        perform a multi-criteria decision analysis. The results provide pointers to interesting 
        areas  for  future  work,  as  well  as  advices  on  design-time  decisions  in  game 
        development.       
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                    Acknowledgements 
        Firstly, I would like to express my sincere gratitude to my dissertation supervisor Dr. 
        Apostolos Ampatzoglou, whose expertise, patience, continuous support, and generous 
        guidance made it possible for me to conduct this project and related research. His 
        immense knowledge and persistent help inspired and motivated me. He has supported 
        my effort in uncountable ways. It was a great pleasure working with him. 
        I  am  thoroughly  grateful  to  Dr.  Tasos  Stylianou  for  his  insightful  comments, 
        suggestions, and encouragement during the course of this project.  
        Last but not least, I would also like to thank all my Professors who put their faith in 
        me. Their knowledge and commitment to the highest standards were a constant source 
        of inspiration. 
         
                     
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        Table of Contents 
        Abstract .......................................................................................................................... 2 
        Acknowledgements ........................................................................................................ 3 
        List of Figures and Tables.............................................................................................. 6 
        1.  Introduction ............................................................................................................... 7 
         1.1  Motivation ........................................................................................................... 8 
         1.2  Aim and Objectives ............................................................................................. 8 
        2.  Literature Review.................................................................................................... 10 
         2.1  Background Concepts ....................................................................................... 10 
          2.1.1  What Is a Design Pattern? .......................................................................... 10 
          2.1.1  Game Design Patterns ................................................................................ 10 
          2.1.2  GoF Design Patterns ................................................................................... 11 
          2.1.3 Software Quality Attributes ......................................................................... 12 
         2.2  Related Work and Contribution ........................................................................ 14 
        3.  Research Methodology ........................................................................................... 16 
         3.1  Research Questions ........................................................................................... 16 
         3.2  Cases and Units of Analysis (Sampling) ........................................................... 16 
         3.3 Data Collection ................................................................................................... 17 
         3.4 Data Analysis ..................................................................................................... 18 
        4.  Findings and Results ............................................................................................... 19 
         4.1  Mappings Between Game and GoF Design Patterns ........................................ 19 
          4.1.1  Implementation of Turn-based Games with Template Method.................. 19 
          4.1.2  Implementation of Agents with Strategy .................................................... 20 
          4.1.3  Implementation of Power-Ups with Visitor ............................................... 21 
          4.1.4  Implementation of Game World with Composite ...................................... 22 
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