Core Animation Reference

Search these docs to answer questions about Core Animation (the QuartzCore framework). Use this skill when working directly with CALayer, layer-backed UIKit/AppKit views, explicit keyframe or spring animations on layer properties, particle systems, or per-frame callbacks via CADisplayLink.

For SwiftUI's declarative animation API (withAnimation, Animation, .animation(_:value:), transitions), use guide-swiftui-animations instead. For SwiftUI immediate-mode drawing, use swiftui/canvas.md and swiftui/graphicscontext.md.

Return Format

Always include:

1. Summary — answer the question concisely.
2. File paths — list relevant files for full details, e.g.:
   • calayer.md for layer geometry, contents, hierarchy
   • cabasicanimation.md for animating a single property between two values
   • catransaction.md for batching, disabling implicit animations, or changing default duration

Files