What is foil-shaders?

Foil Shaders is a SwiftUI library that brings a collection of visual effects called Paper Shaders to iOS and macOS apps, using Apple's Metal graphics technology to run them efficiently on device. Paper Shaders is an existing set of animated visual effects like mesh gradients, swirls, dithering patterns, and paper textures, originally built for the web using WebGL. This project reimplements those same effects natively for Apple platforms so Swift developers can use them without relying on a web view. Developers add it to their project through Xcode's package manager or by editing their Package.swift file directly, pointing at the project's GitHub repository and a specific version number. Once installed, using an effect is as simple as adding a SwiftUI view like AnimatedMeshGradient with a few parameters for colors, distortion, and animation speed. Many effects also come with ready made presets copied from the original Paper Shaders project, and colors can be written as hex codes or in common formats like rgb and hsl. The animated components are considerate of accessibility and performance by default: they respect the system's Reduce Motion setting and pause rendering when the app is inactive or the view is offscreen, though developers can turn either behavior off for specific cases. There is also a companion desktop app, Foil Shader Studio, available as a separate download for browsing and previewing the shaders visually. The project includes a visual comparison system that checks its Metal based output against reference images from the original web based Paper Shaders project, to confirm the two look the same. The README notes this project is still in an early alpha stage before its first stable release, so its programming interface may still change. This is aimed at iOS and macOS developers who want polished, animated background effects in their SwiftUI apps. It is released under the Apache 2.0 license, allowing free use, modification, and redistribution, including commercially.