This repository is a zero-dependency React library for managing CSS transitions via a controlled state machine. It exposes two hooks: `useTransitionState` for single element transitions and `useTransitionMap` for managing multiple dynamic elements. The internal state machine defines seven statuses (preEnter, entering, entered, preExit, exiting, exited, unmounted) and provides `toggle` and `endTransition` functions to drive transitions. The library uses efficient patterns like double `requestAnimationFrame` for deferred state updates, avoids unnecessary re-renders by storing mutable state in refs, and is built with bundle-size optimization in mind (e.g., single-character internal property names). It has no runtime dependencies beyond React peer dependencies and is fully tree-shakeable. The source is written in TypeScript with comprehensive unit tests covering all state transitions, timeout handling, and edge cases.
The Universal Transition Shader is a Godot shader that provides a wide variety of transition effects (wipes, fades, masks, shapes, and clock wipes) with extensive customization options. It uses a grid system to allow for complex patterns like staggering, mirroring, and cell-based animations. The shader is self-contained and can be applied to any CanvasItem in Godot, making it a reusable tool for game developers and creators.
ffmpeg-concat is a Node.js CLI tool and library for concatenating video files with OpenGL-based transitions. It extracts frames from input videos using ffmpeg, applies GLSL transitions between consecutive frames using headless-gl, and transcodes the result to MP4. The architecture is modular with separate modules for frame extraction, transition rendering, audio handling, and final encoding. Key entry points are lib/index.js (library API) and lib/cli.js (command-line interface). The system relies on ffmpeg as a system dependency and wraps it with fluent-ffmpeg for Node.js integration. The code demonstrates solid engineering practices with clear separation of concerns, proper error handling, and test coverage. However, the dependency ecosystem shows signs of age - many packages date to 2018-2019, and the Travis CI configuration uses outdated Node.js versions. The OpenGL-based transition system is the core innovation, allowing complex visual transitions that would be difficult to implement with ffmpeg filter graphs alone. This is a practical tool for video editors and developers needing programmatic video concatenation with visual effects. It's not a research project or data pipeline - it's a production-ready library with CLI support.