Haskell SpriteKit - a Purely Functional API for a Stateful Animation System and Physics Engine

schedule 03:00 PM - 03:45 PM place Grand Ball Room 1 people 3 Attending

Graphics, animation, and games programming in Haskell faces a dilemma. We can either use existing frameworks with their highly imperative APIs (such as OpenGL, Cocos2D, or SpriteKit) or we waste a lot of energy trying to re-engineer those rather complex systems from scratch. Or, maybe, we can escape the dilemma. Instead of a Haskell program directly manipulating the mutable object-graph of existing high-level frameworks, we provide an API for purely functional transformations of a Haskell data structure, together with an adaptation layer that transcribes those transformations into edits of the mutable object-graph.

I this talk, I will explain how I used this approach to architect a Haskell binding to the animation system and physics engine of Apple’s SpriteKit framework. I will discuss both how the binding is structured and how it achieves the translation of Haskell side changes to SpriteKit and vice versa, such that it is sufficiently efficient. Moreover, I will demonstrate by example how to use the Haskell library to implement a simple game.

 
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Outline/structure of the Session

This talk uses Haskell and SpriteKit as concrete technology in its examples, but it requires neither previous experience with Haskell nor with SpriteKit. In a similar vain, the talk is based on Apple’s SpriteKit framework, as there is no reasonable (in terms of effort) way around platform-specific technology if you want something that is simultaneously state-of-the-art, practically useful, and convenient to use. Nevertheless, the concepts explained in the talk transcend the specific technology and are generally applicable.

Learning Outcome

  •  How to wrap a stateful, imperative framework in a nice functional API using Haskell

Target Audience

Developers interested in applying Functional Programming to Animation and Physics Engine

schedule Submitted 3 months ago

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