As at the initial publication of this book, WWDC15 recently completed and gave us a great new SpriteKit demo project for iOS 9 and Xcode 7 named DemoBots.
DemoBots is a SpriteKit project provided by Apple that uses components, state machines, on-demand services, GameplayKit, ReplayKit, and more!
The full project documentation to DemoBots can be found at https://developer.apple.com/library/prerelease/ios/samplecode/DemoBots/Introduction/Intro.html.
To see it in action from WWDC15, see the video and PDF file from the Deeper into GameplayKit with DemoBots keynote:
https://developer.apple.com/videos/wwdc/2015/?id=609
The SpriteKit keynote can be found here:
https://developer.apple.com/videos/wwdc/2015/?id=604
DemoBots's gameplay even has easily editable enemy AI / navigation schemes uses the SKCameraNode introduced in iOS 9 that follows the player and doesn't move the scene around in the view as in past versions of SpriteKit. As we mentioned at the beginning of the chapter, mimicking the tools we see in multiplatform game engines.
We went through a number of topics here in this chapter. We first spoke on why SpriteKit was a welcomed addition to iOS after years of developers only having third-party gaming frameworks, such as Cocos2D and Sparrow. We discussed how SpriteKit fits in the game development ecosystem as rather powerful, multiplatform game engines, such as Unity and Unreal Engine, continue to become more prominent. Next, we went into the SpriteKit game loop and rendering cycle that is used by SKScene. Then, we began to build our demo tile game, SwiftSweeper, and dove more into the basic structure of SpriteKit's most prominent object classes. The iOS 9 assets folder was reviewed in addition to texture atlases and how to animate sprites using these asset tools. Then, we went into the rather complex logic and code that goes into mimicking a tile game such as MineSweeper.
Next, we move on to iOS's 3D game development framework, SceneKit, where we will diverge more towards the visual tools Apple now brings to us since iOS 8 / iOS 9. We'll take less of a code-centric methodology now that we know the basic scene/code structure that both SceneKit and SpriteKit share. SpriteKit scenes can overlay SceneKit scenes, so we will see some of what we hinted at with Apple's own DemoBots demo shortly.