CoreAnimation icons

I've been experimenting with creating pixel-perfect icons using CoreAnimation layers, filters and effects. Also I built a small native AppKit app for testing rendering.

Here a brief overview of some technical details and tools used in process.

Mica App

Mica is Apple's internal tool for UI design, prototyping, animation and inspection, built on Core Animation. Internal resource accessible via Apple's private VPN at https://mica.apple.com

This app looks to be turning 20 years old. It started around the same time as original John Harper's LayerKit project (which later became Core Animation). Today it uses an extended version of CoreAnimation through main internal frameworks LayerKit and MicaKit (all in one MicaKit.framework these days).

I strongly believe Mica was ahead of its time, introducing many features years before they became common in current design tools.

Some of features included: states management and transitions between layer tree compositions, keyframe recorder, pseudo-3D camera control, built-in mesh face/vertex editor, events/signals, scripting language (JS-to-CA/LK/ObjC), extensible architecture with plugins, components and modules. Also seamless integration with Mica Player for iOS with deep hardware support.

Mica can produce some CA tree data — xml, archive, bundle, bundle-cpio (.caml, .caar, .layerkit, .ca, .cadr) that you can load into your app using CAPackage and manage states using CAStateController, CAState, etc. Understanding states and transitions is key to making simple animations and prototypes.

Mica widely used by engineers and designers across the company. Many features you use daily were built or ideated and prototyped using this tool. For example, iOS 6 shredder effect, presented by Scott Forstall was made with it:

Even from an engineering perspective, Mica is powerful CoreAnimation playground, especially with its easy customization and extensibility.

Kite Compositor App

This is another CoreAnimation focused design tool, though currently abandoned.

Available publicly at https://kiteapp.co

It's no surprise it looks similar to Mica, as Kite was developed by an Apple employee who now works on Mica internally.

This app implements many of Mica's concepts and ideas, though without proprietary extended LayerKit functionality.

It can also produce CoreAnimation archives (.caar) that you can use in your apps through CAPackage or other methods.