shoheiyokoyama
Gemini
Swift

Gemini is rich scroll based animation framework for iOS, written in Swift.

Last updated Jul 5, 2026
3.3k
Stars
199
Forks
18
Issues
0
Stars/day
Attention Score
74
Language breakdown
No language data available.
โ–ธ Files click to expand
README

Overview

What is the Gemini?

Gemini is rich scroll based animation framework for iOS, written in Swift. You can easily use GeminiCollectionView, which is a subclass of UICollectionView.

It enables you to make multiple animation which has various and customizable properties, and moreover can create your own custom scroll animation.

Gemini also provides a fluent interface based on method chaining. you can use this intuitively and simply.

collectionView.gemini
    .circleRotationAnimation()
    .radius(400)
    .rotateDirection(.clockwise)

Features

Platform Cocoapods Carthage compatible License Swift pod

  • [x] Rich animation with scrolling
  • [x] Easily usable
  • [x] Highly customizable
  • [x] Several types of animations and properties
  • [x] Supports vertical and horizontal flow layout
  • [x] Supports easing function
  • [x] Supports Swift5.0
  • [x] Fluent interfaces based on method chaining
  • [x] Compatible with Carthage
  • [x] Compatible with CocoaPods
  • [x] Example project with lots of stock animations
  • [x] And More...

Contents

Animation Types and properties

The following animation types are available. See sample code here for details.

- Roll Rotation - Pitch Rotation - Yaw Rotation
  • Scale
  • Custom You can create your own custom scroll animation using multiple properties, rotation, scale, translation, etc.
In addition, you can also customize the following properties for the above animation types.

Cube

It's a cube animation like Instagram. If you would like to customize the cube animation, change cubeDegree. If cubeDegree is 90, it moves like a regular hexahedron.

collectionView.gemini
    .cubeAnimation()
    .cubeDegree(90)

CircleRotation

An animation moves in a circle. You can change circleRadius and CircleRotationDirection.

collectionView.gemini
    .circleRotationAnimation()
    .radius(450) // The radius of the circle
    .rotateDirection(.clockwise) // Direction of rotation. 
    .itemRotationEnabled(true) // Whether the item rotates or not.

3D vector rotation

Available for Roll, Pitch and Yaw animation. These rotation animation are designed based on 3-Dimensional vector. Figure-1 shows direction of rotation based on device.

Figure-1 Pitch, roll, and yaw axes ######

Reference: Event Handling Guide for UIKit Apps

Roll Rotation

Pitch Rotation

Yaw Rotation

Each types of rotation animation has RotationEffect(e.g. RollRotationEffect) and degree of rotation.

Customize RotationEffect (up, down, sineWave, reverseSineWave) and degree of rotation.

In the case of rollRotation, like this:

collectionView.gemini     .rollRotationAnimation()     .degree(45)     .rollEffect(.rollUp)

Scale

The scaleUp gradually increases frame size, scaleDown decreases.

collectionView.gemini
    .scaleAnimation()
    .scale(0.75)
 ย  ย .scaleEffect(.scaleUp) // or .scaleDown

Custom

You can flexibly and easily customize scroll animation. Customize properties of GeminiAnimation.custom such as scale, scaleEffect, rotationAngle, translation, easing, shadowEffect, alpha, cornerRadius, backgroundColor, anchorPoint, etc.

The animation of gif is customized in the following way:

collectionView.gemini
    .customAnimation()
    .translation(y: 50)
    .rotationAngle(y: 13)
    .ease(.easeOutExpo)
    .shadowEffect(.fadeIn)
    .maxShadowAlpha(0.3)

Or right side of gifs is customized as follows:

collectionView.gemini
    .customAnimation()
    .backgroundColor(startColor: lightGreenColor, endColor: lightBlueColor)
    .ease(.easeOutSine)
    .cornerRadius(75)

There are more sample code at CustomAnimationViewController.swift.

Easing function

Gemini supports various easing functions based on distance of scroll.
  • linear
  • easeInQuad
  • easeOutQuad
  • easeInOutQuad
  • easeInCubic
  • easeOutCubic
  • easeInOutCubic
  • easeInQuart
  • easeOutQuart
  • easeInOutQuart
  • easeInQuint
  • easeOutQuint
  • easeInOutQuint
  • easeInSine
  • easeOutSine
  • easeInOutSine
  • easeInExpo
  • easeOutExpo
  • easeInOutExpo
  • easeInCirc
  • easeOutCirc
  • easeInOutCirc

Shadow effect

Default value is ShadowEffect.none. Return shadowView in your custom class, which is a subclass of GeminiCell.
  • fadeIn
  • nextFadeIn
  • previousFadeIn
  • fadeOut
  • none
class CustomCollectionViewCell: GeminiCell {
    @IBOutlet weak var customShadowView: UIView!
    override var shadowView: UIView? {
        return customShadowView
    }
}

Usage

  • Use Gemini classes
Gemini is designed to be easy to use. Use GeminiCollectionView and GeminiCell. These classes is subclass of UICollectionView, UICollectionViewCell.
  • Configure animation
Configure animation with fluent interface based on method chaining. You can develop expressive code that enhances readability.
  • Call function for animation
Finally, call animateVisibleCells() in scrollViewDidScroll(_:)
NOTE: If you want to adapt animation immediately after view is displayed, call animateCell(:) in collectionView(:cellForItemAt:) and collectionView(_:willDisplay:forItemAt:).
// Import Gemini
import Gemini

// Inherite GeminiCell class CustomCell: GeminiCell { ... }

// Conform to UICollectionViewDelegate and UICollectionViewDataSource class CustomViewController: UIViewController: UICollectionViewDelegate, UICollectionViewDataSource {

// Inherite GeminiCollectionView @IBOutlet weak var collectionView: GeminiCollectionView!

...

// Configure animation and properties func configureAnimation() { collectionView.gemini .circleRotationAnimation() .radius(400) .rotateDirection(.clockwise) }

// Call animation function func scrollViewDidScroll(_ scrollView: UIScrollView) { collectionView.animateVisibleCells() }

func collectionView(_ collectionView: UICollectionView, willDisplay cell: UICollectionViewCell, forItemAt indexPath: IndexPath) { if let cell = cell as? GeminiCell { self.collectionView.animateCell(cell) } }

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell { let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "CustomCell", for: indexPath) as! CustomCell self.collectionView.animateCell(cell) return cell }

See Example, for more details.

To run the example project, clone the repo, and run pod install from the Example directory first.

Requirements

  • Xcode 10.2.1
  • Swift 5.0

Installation

CocoaPods

Gemini is available through CocoaPods. To install it, simply add the following line to your Podfile:

pod "Gemini"

Carthage

Add the following line to your Cartfile:

github "shoheiyokoyama/Gemini"

Author

Shohei Yokoyama

License

Gemini is available under the MIT license. See the LICENSE file for more info.

ยฉ 2026 GitRepoTrend ยท shoheiyokoyama/Gemini ยท Updated daily from GitHub