Computer Games: F917 10/11/12 F917 10/11/12 Page 1
Contents Games Design Brief 3 Game Design Document... 5 Creating a Game in Scratch... 6 Adding Assets... 6 Altering a Game in Scratch... 7 If statement... 8 Creating a Game in GameMaker... 9 Adding Assets... 9 For Loop... 10 Altering a Game in GameMaker... 10 Creating a Game in Alice... 11 Adding Assets... 11 Collision Detection... 12 Testing your game... 13 Observation Checklist... 14 Test Strategy... 14 Test Plan... 15 Sample Test Plan... 15 Test Case... 15 Test Data... 15 Predicted result... 15 Actual result... 15 Yes/No... 15 Comment... 15 F917 10/11/12 Page 2
Sample Test Plan (Continued)... 16 Test Case... 16 Test Data... 16 Predicted result... 16 Actual result... 16 Yes/No... 16 Comment... 16 Evaluate a computer game... 16 Narrative/Background story... 16 Level/environment... 16 Gameplay/mechanics... 17 User Interface... 17 Report Template... 17 Justifying any changes... 17 Identifying improvements... 18 Evaluating the Game Environment... 18 F917 10/11/12 Page 3
Introduction (L4, L5, L6) This document contains the on-line content for Learning Outcome Two of Development Materials. The parenthesised letters and numerals to the right-hand side of each section title indicate the level for which the material is written. However, don t be constrained. If you are studying at a lower level, level 4 or 5, and what to enhance your knowledge by also reading material written for a higher level, please feel free to do so. There is nothing wrong with aiming for excellence. Game Design Brief (L4, L5, L6) Many people have an idea or concept for a game and are unsure how to develop this into a reality. A game design brief is a good place to start, even for a hobbyist or amateur. By writing down and developing your idea, you can develop a prototype for a game and identify the possible pitfalls and options available. Paper prototyping is a good way to test your game and allows you to see how it would work out. This is the ideal way to test the usability of your game and is a great way to find out what your players want before you begin coding. F917 10/11/12 Page 4
Game Design Document The Game Design Document (GDD) is the plan or blueprint for your game; it contains the detail necessary to build the game so that everyone in the team is working to the same plan and design. The games industry does not have a generic GDD as the varying genres make it difficult to generalize this document. Think of your GDD as a reference document, your primary source of reference from which the game will be produced. This is a living document which will be amended and updated throughout the development process. The game design document is the communication tools which all members of the team access to ensure they are working to the same specification. These assets were used in the game developed by the HNC Computer Games Development student and used in their game Animapocalypse.. F917 10/11/12 Page 5
Creating a Game in Scratch (L4, L5, L6) Creating a game in Scratch is fun and easy. Scratch has created a wealth of information to help you develop your skills with the program. A good place to start is with the Getting started guide.pdf Within the folders in Scratch some sample games have been created for you, including a Pong game. Adding Assets It is possible to add assets to Scratch in the form of graphics (Sprites), Backgrounds or Sounds. Click on the relevant tab to display these options: F917 10/11/12 Page 6
To add sprite graphics there are 3 possible options. Choose new sprite from file this option allows you to import a file you have created elsewhere or downloaded Paint new sprite this option allows you to use the drawing tools to create your own sprite Get surprise sprite this option choose a random sprite from the Scratch file directory To add a background: Paint this will open the paint editor where you can create your own background using the variety of tools on offer. Import will open the file import dialogue and allow you to select a background file from your computer. Camera uses your webcam to take a photograph and makes this your background. To add a sound: Record if you have a microphone you can record your own sound effects this can be great fun. Try a door opening, telephone ringing, screaming etc. Import as with the background and sprites, you can also import a file from your computer. Altering a Game in Scratch Scratch makes it easy to amend your game by altering the code used in the game. Dragging and dropping the code fragments is easy and you should work through some of the online guides and sample games available from the Scratch website to ensure your understanding. F917 10/11/12 Page 7
The range of amendments you could make to your game are almost endless but some popular alterations are: Changing the direction of assets by amending the x or y co-ordinate values Speeding up or slowing down movement e.g. speed of car Changing behaviour e.g. bouncing at edge of screen Changing costumes on sprites If statement The ability to control the flow of your program is invaluable to a programmer. The if statement is a conditional statement which tests to see if a particular statement is true or false and then executes the next section of code. One of the important functions of the if statement is that it allows the program to select an action based upon the user's input. For example, by using an if statement to check a user entered password, your program can decide whether a user is allowed access to the program. Without a conditional statement such as the if statement, programs would run almost the exact same way every time. If statements allow the flow of the program to be changed, and so they allow for the use of algorithms and more interesting code. F917 10/11/12 Page 8
Creating a Game in GameMaker (L4, L5, L6) When you open GameMaker 8 for the first time you will have the opportunity to follow the Your First Game Tutorial in the panel on the right hand side. If you are new to games development, this is an excellent resource to start with. There are three example games available to you within GameMaker street racing, treasure and tutorial 1. Load and play each of these games to gain some insight into the possibilities with GameMaker. An array of resources is available through the yoyo games website, and it is suggested that you should browse the site and view games that other students have created. GameMaker has been used in industry and one current popular game on the mobile download market is They need to be fed. Now you ve seen what GameMaker can do, have a go at making a Pong Game for yourself. Adding Assets Assets can be added to your game in the form of sprites, backgrounds, sounds, objects and rooms. With each of the assets you have the option to load existing assets from file. With Sprites and Backgrounds it is possible to make alterations within GameMaker. Sound files can be loaded and saved. F917 10/11/12 Page 9
Objects are defined by yoyo games as objects are either visible or invisible, and these objects perform actions. Actions to be performed are performed on usual occasions, these occasions are called events. An object can make an action when it is created, before it is destroyed, when it collides with an object, when a key is pressed, when the mouse is hovering over it, and many more. The object properties dialogue box allow for a huge array of choices and actions. Sounds files can be loaded and tested within this dialogue box. For Loop When you wish to repeat an action multiple times, it is an efficient method of coding to use a loop. Loops come in several formats for loop, do-until, while etc. The simplest loop is a for loop. Altering a Game in GameMaker There are several ways to alter your game in GameMaker, either through the interface, by editing your graphics, or by changing the code itself. The best way to become confident is to make as many small games as you can. F917 10/11/12 Page 10
Creating a Game in Alice (L4, L5, L6) When you first start Alice you have the opportunity to follow through a few Tutorials this will help you to understand the basic concepts of the package and is highly recommended. Programming in Alice is easy as it is done by pointing and clicking, dragging and dropping, selecting from menus, and some typing. Adding Assets The first thing we need to do in Alice is to build our World and add our objects and characters. Click the Add Objects button and play around with this for a while. It can be great fun to create an amusement park etc. Let s create a throwing/catch game. Click Add Objects and select People. Choose 2 people you wish to have in your world and one object to act as the ball (I choose a basketball). Your Object Tree should look similar to this 2 characters and one ball. F917 10/11/12 Page 11
Add some code segments to pass the ball from once character to the another and even have a conversation! Altering a Game in Alice The code segments make it very simple to alter the game. By clicking on any of the dropdown arrows in the code you can make any necessary alterations. Collision Detection Within a game environment collision detection is one of the hardest problems to simulate. Multiple objects moving in 2D or 3D space could overlap and this has to be spotted without using excessive amounts of CPU power. Wikipedia defines collision detection as Collision detection typically refers to the computational problem of detecting the intersection of two or more objects. While the topic is most often associated with its use in video games and other physical simulations, it also has applications in robotics. In addition to determining whether two objects have collided, collision detection systems may also calculate time of impact (TOI), and report a contact manifold (the set of intersecting points).[1] Collision response deals with simulating what happens when a collision is detected (see physics engine, ragdoll physics). Solving collision detection problems requires extensive use of concepts from linear algebra and computational geometry. You can mimic collision detection easily in Alice by moving the camera and checking its distance from an object. F917 10/11/12 Page 12
More advanced collision detection is possible and information can be found on the Alice Forums and website. Testing Your Game (L4, L5, L6) You will almost certainly have heard of Games Testers these are people who are paid (in most cases) to play and test games for the large games companies. The games industry spends millions of dollars each year on testing; this gives an indication of how pivotal it is to the success of a game. Games need to be tested for usability, fun, difficulty, to ensure they are error free etc. As you develop games in Scratch, Game Maker or other applications you should regularly test your projects. There are many ways to accomplish this you may post your games online and seek feedback from the community. You may create a questionnaire focusing on particular questions or areas; ask friends and family to give you honest feedback. This feedback will help improve your game and you should not take criticism personally, but work to overcome the issues. Here are a few questions to ask your testers: Did you enjoy the game and would you play again? Did the game feel too long/short? Did you understand the goal of the game? What was it? Did you understand the instructions? Did you think it was too challenging/not challenging enough? Did you like/dislike the graphics/sounds? Did the pace feel too fast/slow? Wikipedia defines games testing as a subset of game development, is a software testing process for quality control of video games. The primary function of game testing is the discovery and documentation of software defects (aka bugs). Interactive entertainment software testing is a highly technical field requiring computing expertise, analytic competence, critical evaluation skills, and endurance. F917 10/11/12 Page 13
Observation Checklist A simple way of testing usability and ease of use is to observe players playing your game, this maybe friends and family initially. By observing their behaviour and progress through the game you can gauge where problems and difficulties might arise. Constructing a questionnaire can aid this process and ensures you consistently evaluate each individual. The following questions could be asked outright to the individuals or completed through observation: Did you manage to start the game successfully first time? Were the controls easy to use and understandable? How far through the game did you progress? Did you find it easy, average or difficult to play the game? Could you easily defeat the enemies? Did the sound effects and music add to the ambience of the game? Did the graphics add to the playability of the game? Would you play the game again? Any comments: Test Strategy During your planning stage, it is a good idea to develop a testing strategy. This will outline how you propose to test your product and ensures all key players such as managers, testers and developers are on track. Within the games industry testing is an on-going feature. Many companies build test areas specifically for this. These are all for testing of movement, sprite life cycles and enemy movement. They may also check for score boards, health areas, pause functions, gravity and physics the list is almost endless. Creating a test plan is the most comprehensive way to test your game throughout and at the end of development. Many large games companies employee huge numbers beta testers to test their games before they are released to the public. F917 10/11/12 Page 14
Test Plan The test plan is the detailed specification for the testing of your game. Test plans consist of a number of test cases which test a specific object or action. Tests have to execute the test cases at least once and report any defects founds. The developers then fix the issues (known as bugs) and the testers re-test. This is an on-going cycle. Sample Test Plan Test Case Test Data Predicted result Actual result Yes/No Comment Game Load Test if game loads Game loads up properly, loading screen shows Games loaded as expected, loading image showed up Yes Loading screen was changed for visual effect Images load properly Test that images are loading and the sprites are inserting correctly All images load properly and sprites All worked well Yes All worked well Start screen Test it works correctly and all options are available Start screen works fine, music plays All but one option on the start screen worked No The controls option did not work Test clouds scroll Test to see if the clouds scroll on a loop All will seamlessly move There is a slight glitch in the transition of scrolling No The picture for the clouds will need to be aligned to stop glitch Player attack Check if player has attacked enemy and that enemy loses health and dies Enemy will be hit then after they lose all their life they will die and disappear All worked well Yes All worked fine Test health potions Check that health potions appear in the right place and when they are touched they add health and disappear All are expected to add health All worked as expected Yes As expected F917 10/11/12 Page 15
Sample Test Plan (Continued) Test Case Test Data Predicted result Actual result Yes/No Comment Test flame in dungeon Ensure flames appear and hurt player if contacted Cause loss of health All flames appear but player does not lose health No Add impact to lose health Evaluate a Computer Game (L4, L5, L6) Evaluating your game may prove difficult since you are naturally proud of your achievement and will have worked long and hard to produce your best work. However, being able to be critical of what you have produced and to identify areas of improvement is a necessary skill for any games developer. There are a number of areas which you can evaluate. Narrative/Background Story Before you developed your game, you probably had a clear idea of the narrative or background, but did you manage to convey this in your finished product? Does the player understand the sequence of events that have lead them to their start location? It is possible that this narrative may continue throughout the game play is it consistent? Does the narrative still represent the original idea? Could it be improved in any way? Not all games have a narrative, for example, a puzzle game could be improved by a description of how to progress through the levels of the game. Level/Environment You may have developed your own graphics or found some open source files. Whatever the mix, it can be difficult to create or source the perfect graphics every time. Could there be improvements here? Do the graphics give a feeling of realism? Are they aesthetically pleasing? Do the graphics work well together and set the mood for the game? F917 10/11/12 Page 16
Gameplay/Mechanics Being able to play the game from start to finish allows a sense of achievement. Does the game flow well? Are the challenges within the game too easy or too challenging? Can the player access and escape from all areas? Can the player run, jump, shoot etc. as necessary? User Interface How intuitive the player finds the controls can be very important. Are the controls natural? What improvements could be made here? Can the game be played with a mouse and keyboard? Report Template It is likely that your report will cover many of the items mentioned above and will look specifically at improvements and comments around the areas of: Introduction Narrative Level/Environment Gameplay/Mechanics User Interface Conclusion Justifying any changes Whilst it is important to evaluate the game and identify any improvement, it is also good practice to identify how consistently the game has been developed with the original design. Reading back through your original design document will help to identify any changes that have been made. Many of these will have justifiable reasons. For example, it may have been necessary to remove a bug identified during testing, or perhaps your original plans had been too optimistic given the timeframe and programming skills available. F917 10/11/12 Page 17
Identifying improvements Identifying improvements can be easy you may have run out of time, did not have the expertise of a graphic designer or 3D modeller, had to produce your own sound effects etc. Some or all of these issues could be improved upon given greater resources such as time and money. Writing a game review is an art in itself and jobs in freelance game reviewing are highly sought after. The best way to understand the practicalities of writing a game review is to read through some online. Have a look at the Games TM website which always has up to date game review on display: http://www.gamestm.co.uk/category/reviews/ Producing a user review allows you to highlight the strengths and weaknesses of the game. Evaluating the Game Environment Every game development environment and programming language has limitations but these are often out-weighed by the strengths. Ease of use and the quick turnaround of games development can be a huge draw and advantage of many environments. The use of online support materials and user forums can also be beneficial and may influence your choice of environment. F917 10/11/12 Page 18