WORKING WITH 2D TOOLS IN UNITY

ET13 – Week 15
Creating an entire Shooting Game / and a new way of organizing assets

• Create a new 2D project on your Save Here drive: yourName wk15
• Select main camera in Game view to select 5:4 aspect ratio
• Select camera Orthographic; set size to 6
• Save scene as Main
• Download WK15 Assets folder

In the Assets folder in the project window:

• Create a new folder called “background”
• Import “Star_Sky.PNG”; set pixels per unit to 50 in the properties window
• Drag in to Hierarchy window (always apply when promted): position should be x=0/y=0/z=0
• Import “scrollBackground.CS” script into background folder
• Select Star_Sky object in hierarchy, and drag ScrollBackground script into it’s property bar
• Select script from folder and examine
• Duplicate Star_Sky in hierarchy and set position to 0/20/0
• Zoom out and run; check in scene view

PLAYER

• Create new folder “spaceship”
• Import “spaceship.PNG”; set sprite mode to multiple; apply
• Open sprite editor; select slice type “grid by cell size” x=116, y=140; hit slice and apply
• Open sprite tray to show cells; shift-select all and drag to hierarchy
• A new animation is created; save as “spaceship”; double-click on object to zoom
• Select spaceship in hierarchy and position at 0/-5/0; scale at 1/-1/1 to invert
• Add Component/physics2D/polygon collider; check IS TRIGGER
• In Sprite Renderer select Sorting Layer/add/+ new layer name “player”
• Run and examine

Meteors!

• Create new folder called “meteor”; import “meteor.PNG”; set to multiple and apply
• Select Sprite Editor; slice type is AUTOMATIC; slice and apply
• Open meteor tray in assets folder; shift-select all; drag to hierarchy; save as “meteorAnimation”
• Double-click to zoom; select sorting later to “player”
• Add component/physics2D/circle collider; add Rigidbody 2D; set gravity scale to 0
• Close sprite tray; drag Meteor_0 object to folder creating a PREFAB
• Test. Remove original Meteor_0 from hierarchy.

BULLETS

• Create new folder called “bullets”; import “bullet.PNG” into new folder
• Set Pixels Per Unit to 400; Drag bullet into hierarchy (apply)
• In Sprite Renderer property, change color to bright (green)
• Add component/physics2D/circle collider; add Rigidbody 2D; set gravity scale to 0
• Drag bullet object to folder creating a PREFAB
• Remove original “bullet” from hierarchy.

SHREDDERS

• Create a new EMPTY game object; rename it “shredder”; position at 0/-10/0
• Add boxCollider 2D; size x=16/y=1; check IS TRIGGER
• Duplicate; position new shredder at 0/10/0
• Test in scene view for positions

SCORING AND USER INTERFACE

• Add GameObject/UI/Text; this creates a canvas overlay in exaggerated view.
• Rename text object “score” in canvas pull-down. Double click to zoom; keep zooming out
• Move “new text” box to upper left of Canvas; change text box to “0”
• Check “best fit” to select; change color to White.
• Run test.
• Add another GameObject/UI/Text; rename it “game over”
• Under Rect Transform, set W = 200 / H = 100; change text box to “Game Over!!!”
• Check “best fit”; position 0/0/0; center alignment; change color to Red.
• Test
• Disable check box at Text (Script) and test again

SCRIPTING CONTROLS!

• MOVING
• SHOOTING
• BULLETS
• METEORS
• SPAWNING
• SHREDDING
• CONTROL…

Game Control

• Create new EMPTY game object; rename it “controller”
• Go to Assets folder and create a new folder called “Scripts”
• Import “gameControl.CS” script file into new folder
• Examine in Inspector
• Select “controller” object from hierarchy; drag GameControl script into its inspector
• Select “score” for score text and “GameOver” for game over text

Meteor Control

• Go to Meteor Folder; Import “meteorMover.CS” script file
• Examine in Inspector
• Select the “meteor_0” prefab in the folder; Drag new script into its inspector window.
• Speed is set for -2; Drag a meteor prefab into hierarchy and run test.
• Remove meteor from hierarchy when done.

Spawn

• Create new EMPTY game object; rename it “meteorSpawn”
• Import “meteorSpawn.CS” script file
• Examine in Inspector
• 3 WAYS to attach script:
• Drag on to object properties
• Drag on to object in hierarchy
• Select as component  
• Select the “meteorSpawn” object in hierarchy; Drag new script into its inspector window.
• Position object at 0/8/0; select “meteor_0” for the Meteor Prefab field.
• Test run in game and scene views; observe activity in hierarchy!!

Shredder/destroyer

• Go to “scripts” folder; Import “DestroyOnTrigger.CS” script file
• Examine in Inspector
• Drag on to both Shredder objects.
• Test run in game and scene views; observe activity in hierarchy!!

Ship Controller

• Go to “spaceship” folder; Import “shipControl.CS” script file
• Examine in Inspector
• Find L/R move commands
• Find shoot and bullet controls
• Find collision control
• Drag on to “spaceship_0” object
• Select “controller” for Game Controller field and “bullet” for Bullet Prefab field
• Test run in game and scene views; control with L/R and spacebar
• Observe activity in hierarchy, no movement, no collisions!!

Bullet Control

• Go to “bullet” folder; Import “bullet.CS” script file
• Examine in Inspector
• Add script to “bullet” prefab inspector; NOTE speed adjustment (10)
• Test run…… in silence!

AUDIO!

• Go to Assets folder; Import 4/18/16.mp3 audio loop (or your choice)
• Select “spaceship” object in hierarchy; Add component/Audio/audio source
• Select 4/18/16.mp3 for AudioClip; Select Loop and Play On Awake
• Go to Assets folder; Import quick_laser.ogg (or your choice)
• Select “main camera” object in hierarchy; Add component/Audio/audio source
• Select quick_laser.ogg for AudioClip; DO NOT select Loop and Play On Awake
• Go to “scripts” folder; Import “audioScript.CS” script file
• Select “main camera” object in hierarchy; Drag new script into its inspector window
• SAVE!
• Test run!!

MIDI description and tutorial

Search the net (or teacher's folder) for .MID files

Audition MIDI files from media player. MIDI files are the vectors of a musical performance. The final performance of a MIDI file is determined by the local synthesizer (internal or external) in the case of Windows machines it is the MS SoftSynth.

Editing MIDI, however requires a sequencer/editor program that outputs the .MID file format.

To convert MIDI to audio, patch the output of the Media Player to be recorded to Sound Forge; or import the MIDI file into ACID and save as audio.

Size comparison:

After the file is converted, it can then be brought into GameMaker as a WAV or MP3 to preserve the actual performance of your synthesizer but be aware of audio file size. Any audio file much over a MEG can crash GameMaker on load or playback. Save after every import!! MIDI files can be played in GameMaker as background music providing the most efficient format for music in games.

THE GAME DESIGN SEQUENCE

The Main Concept - The Goal/Topic
Every game must have a clearly defned goal. This may seem obvious but it is a very common mistake. Game design goals are the absolute difference between a good and bad game. Some times the importance of clear goals does not become evident untill later in the development cycle, and then it may be too late. The topic must resonate with the player and the game play; and remember, the number one job is to be the advocate for the player!

Research and Prep

Once a concept has been decided on and a goal defined, everything about this topic must be researched. The best game designers immerse themselves in their game's topic, it's world, and it's language.

Design Phase

This is where the play mechanic is applied. What makes your concept a game? Why would it be fun? Would it be fun using physical pieces? or does it have to be digital? Will it be replayable for hours? or a casual couple of minutes? This is where the concept, the goal and the main topic is made to be playable.

User Interface

This applies to both physical and digital games. It also applies to both 2D and 3D gaming. How does the user interact with the game? Is the player an avatar (3rd person, remove)? first person? Do we use the cursor keys? a mouse? on-screen buttons? special game controller? joystick? And that's just the I of I/O. For the output, how does the game feed back to the user? Heads-up display? sound? vibration?

Game Play Mechanic or Structure

How do we maintain the fantasy of the game and still have a practical system? a working piece of software? The game play still needs to center on the main concept. Does the complexity of the the design exceed the limits of the available tools? Can the tools deliver the suspension of disbelief? Can the player find the optimum game experience that allows the attainment of flow? Remember, too many features can also just get in the way! How can you empower the user within practical restraints?

Programming Structure

This is where the concept and game mechanic must be laid out as a logical flow chart to be created in software. All of the commands and instructions that are to be engineered must be possible with the authoring/programming tools. This is where all variables and routines need to be clearly defined and proven capable. All resources, such as memory, storage space, processor speed; need to be mapped out and tested to show if the game will actually run on the platform hardware. The program needs to be stable and bullet-proof to the user's every possible action. Code must force the desired action and still be as elegant and efficiant as possible.

Pre-production

If all of the above plans have proven themselves, then documentaion needs to be formalized. Commit all design features to paper. Define the I/O structure and the game play mechanic in terms of programming instruction. Reconcile the player's experience with the technical considerations.

Programming Phase

This is the easiest part of the process, believe it or not! Though it is repetitive, it is generally very straightforward. It requires patience, acquired skill, and dedicated focus. It cannot be rushed or under done. In a sense, this process requires as much "flow" as the actual game play itself.

Playtesting

Needless to say, this activity is as important as all of the other design procedures put together. Playtesting should be started the moment any part of the game is playable. And testing will need to happen again and again, for every possible combination of the program. Sometimes this happens just to find (and kill) the bugs; sometimes this happens to determine the target audience of the game for marketing purposes. But again, the main job is for the benefit of the end player.

Review & Repeat (if neccessary!)

Once the game is playable; or released; the feedback will never stop. Everyone is a critic. As a designer, the decision rests on you as to whether the game is complete. But the public is the final judge. If they don't buy the game, you lose the money AND your message as a game developer is not heard. If you are satisfied that you have met all or most of your original goals, celabrate; and start planning your next project!!

(Special thanks to Chris Crawford)

Continuation of in-class demo project: adding scoring engine, level navigations, balancing game play.