SpriteKit has gradually emerged as the first-choice framework for many iOS game and app developers across the globe. Some interesting features of Apple’s very own game development system have been highlighted here.
The release of iOS 7, back in September last year, was accompanied by a new tool for 2D game and app developers. Apple created and launched SpriteKit, a user-friendly animations and graphics rendering tool, which had the potential to overtake the Cocos2D framework in terms of popularity. One year on, and that is precisely what has happened – with most iPhone app developers preferring to work with SpriteKit instead of having to learn up the other game development tools. The recently launched iOS 8 platform is completely compatible with SpriteKit too. We will here deliberate on some of the main advantages (and some probable flaws) in SpriteKit:
- High-end content support – Efficient game-rendering is not the only thing SpriteKit is about. Developers can use the framework to work with a vast range of content – from text and textured/non-textured rectangles (which are also called ‘sprites’), to video files. Figures that follow certain CG paths can also be specified. The high frame rate rendering capabilities of SpriteKit ensure that the quality of game development never suffers.
- Learning to use SpriteKit – Relatively simple, thanks to the compact nature of the SpriteKit infrastructure. Learning to create a ‘Scene’ (rendered by the SKView object) is the first thing new developers have to do. These ‘scenes’ can be included and customized in the responder chain, to add other personalized features and controls to games. You will need Xcode 5.0 to start off working with SpriteKit.
- Real-time previews – This is one feature that has hugely contributed to the adoption of Spritekit at leading iPhone app development companies. With the built in ‘Particle System Editor’, coders can check out previews, and make essential changes, in the layout of games (via particle emitters). There are several templates embedded within the editor. All the ‘particles’ are fully customizable as well. The Particle System Editor combines well with the Utility Panel, to keep developers in charge of their games and apps.
- Cross-platform support – SpriteKit is not going to be of much help for programmers interested in cross-platform mobile app development. The framework has been created by Apple, and can be worked with on iOS and Mac OS X (we hope Yosemite would support it too) systems. Certain SpriteKit games can be ported to Android – but the game loses many of its features during the process. You use SpriteKit, you stay with iPhone apps!
- The use of ‘actions’ – Defined in the SKAction class are small objects called ‘actions’. They are responsible for instructing the nodes about the types of animations that are to be processed by the ‘scenes’. Broadly speaking, ‘actions’ can be of two types – those used for single-frame animations and the ones for multiple frames rendering. Professional iOS app developers frequently create ‘sequences’ (combinations) of ‘actions’ – so that the latter are repeated in a loop, and complex, interesting effects are created.
- Sprite nodes enhance user-convenience – Adding content to the SpriteKit application is very simple – thanks to the presence of built-in Sprite nodes. For creating content in a ‘scene’, ‘spaceships’ have to be created – and the latter can be made up by using the objects residing in the SKSpriteNode class. Untextured figures (mostly rectangles) are used as placeholders, which are then seamlessly rendered into textured Sprites – without causing any changes in the overall tech specs of your game or iPhone app. To cite an example, a complete mobile app for kids includes close to a hundred (maybe more) of Sprite nodes. The hierarchy is like this: ‘Spaceship’ is the parent of game visual elements, and node is the parent of ‘spaceship’.
- Support for game physics – SpriteKit is one of the best app frameworks for adding interactive physics classes and elements. While creating a ‘scene’, coders only have to define the attributes correctly – and the program would add the requisite physics to the stage (along with gravity). What’s more, the physics can be tracked as well, with the help of downward vectors.
- Implementing customized OpenGL codes – The second blip in the otherwise excellent SpriteKit framework. For certain games, iPhone app development professionals need to write out and use their own OpenGL codes, and SpriteKit, till date, does not support that. The only way OpenGL can be integrated is by moving over (or remaining with) the Cocos2D game development system. Of course, there are other OpenGL-compatible app frameworks out there as well.
- Content rendering and animation – Okay, time to look at the chief purpose for which SpriteKit is used. As already highlighted above, all forms of game content have to be arranged in ‘scenes’ – and the views (under SKView) have to placed inside the designated window, for animation and rendering. The per-frame logic of any ‘scene’ depends on the duration of time for which the latter is presented. Scene delegates and/or subclasses can also be created inside SKScene (mostly for additional app functions and tasks).
- Performance – With SpriteKit being backed up by the entire API designing system of Apple (for 2D games), it is not a surprise that it aces on the speed and ease-of-usage counts. iOS app developers and/or coders who work mainly with Objective-C do not need to learn any new languages/development systems. There are many online tutorials, which can help new users leverage the full API power of SpriteKit in their games.
- Runtime textures – Yet another point that has endeared SpriteKit so much to iPhone app developers. For applying a picture (untextured) to multiple sprites, you generally have to first load the image file in your application bundle – via which the ‘texture’ is created. However, on SpriteKit, textures can be created in the runtime environment. A bunch of textures, known as ‘texture atlases’ can be used in 2D frames. Atlases are particularly great for improving the rendering quality.
- Creating sprites from videos – Most frameworks do not allow developers to render videos in sprite sheets. This ‘apparently difficult’ task is one of the most talked-about features of SpriteKit. Video files of varying resolution and quality can be added to Sprite sheets. In addition, app and game developers can use SpriteKit to add cool effects/visual elements to images.
All reusable graphical data is stored in the textures created in SpriteKit, sparing developers the trouble of creating them all over again. New classes can be defined and subclasses can be formed from the nodes (which come from UIResponder). SpriteKit ranks high on the reliability front too. All that developers need to start using it is a working knowledge of Xcode and familiarity with Objective-C programming. Not surprisingly, more and more of them are taking to SpriteKit everyday!
Do you use SpriteKit?