Unity 2D Toolkit

2D Toolkit

• $65 on the Asset Store
• Current version is 2.00/2.10
• This is based on 1.92 (breaking changes with 2.0)
• http://unikronsoftware.com/2dtoolkit/

Cameras

• Standard Unity Camera in Isometric mode
• Pros: Familiar, scrolls easily
• Cons: Scales, rather than uses pixel-perfect display
• tk2dCamera
• Pros: Uses pixel units
• Cons: Doesn't behave like a standard Camera
• Bottom-left is always origin
• Must adjust items within scene to scroll

Sprite Collection

• Asset
• Builds sprite sheets out of individual images
• Optimizes based on Camera/Player settings
• Advantage over Orthello/Futile/etc.: you don't need an external program for this
• Allows you to edit bounding boxes (polygon mode)

Sprite Animations

• Asset
• Requires Sprite Collection
• A link between "Sprite Collection" and "Animated Sprite"

Sprite

• Requires Sprite Collection
• Is a Unity object that can take other components

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Animated Sprite

• Requires Sprite Animation
• Uses Sprite Animation vs. Sprite Collection
• Play("animationName")
• IsPlaying("animationName")
• Stop()

Static Sprite Batcher

• Used to bake down multiple sprite objects into a single batch for performance

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Text Mesh

• Requires a BMFont definition and image
• BMFont: http://www.angelcode.com/products/bmfont/
• Glyph Designer (Mac)
• You can also draw your own manually (but hard to troubleshoot)
• Can update dynamically (call Commit() afterwards)

Patterns I Use

Warning: may contain anti-patterns

Creating Moving Objects

• Sprites still behave as 3D objects, so lock Z movement and X/Y rotation
• Use a Collider generated by the Sprite Collection
• RigidBody.AddForce(vector, ForceMode.VelocityChange)

Creating Platformer Movement

• Use CharacterController
• isGrounded
• Move method returns detailed collision info (side/above/below) immediately
• Haven't found anything (free) that replicates this
• CharacterController uses a capsule collider
• Tweak at runtime to figure out the proper Step, Height, Radius, and Skin Width
• Remember that capsule collider curves along Z axis
• Must disable the Box Collider (set isTrigger, possibly in your custom controller script)

Creating Platformer Movement

Script from:�https://www.youtube.com/watch?v=EW0phq6xoJk&list=PLA5781666685406E1

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• Applies its own gravity rather than trying to use physics (feels tighter and more controlled than built-in physics)
• Can adapt this script to use input from an AI logic script

"Is it a...?"

When interacting with other objects (i.e., triggers):

if (obj.GetComponent<MyType>() != null) {

// do something

}

​

• Components define object capabilities, even if I don't interact with their methods or fields
• There are probably better ways to do this.

Layering / Extending Components

• Develop general components which are used by more specific/variant components
• Example:
• AIMotor knows about the Unity CharacterController
• WanderAI, HopWanderAI, etc. read and write exposed fields on AIMotor to determine state and move the NPC
• Example:
• PlatformerController knows how to move the character around; doesn't care what it's attached to
• PlatformerPlayerAnimation is attached to a tk2dAnimatedSprite and inteprets exposed state fields on PlatformerController to animate it

Destroyed Objects Become Null

• You can keep references to other objects in your components, then test if they are destroyed by checking whether they're null
• Example:
• AISpawner has a maximum number of spawns, and keeps a list of enemies it has spawned
• When an enemy is killed, it is destroyed with DestroyObject
• When AISpawner fires, it goes through the list and removes all NULL objects, then tests whether it is under its spawn limit
• This isn't exactly how .NET normally works

Stuff I'm not familiar with...

Sliced Sprite

• Used to create "windows," etc.

Clipped Sprite

• Displays a clipped rectangle from a sprite

Tiled Sprite

• Creates an area filled in with a repeated pattern

Tile Maps

• Beta
• Allows you to "paint" a map based on a tileset
• Can import .tmx files