Jstrokes

Jstrokes is a term used in computer graphics to describe methods and software for rendering and processing stroke-based graphics in JavaScript environments. It encompasses algorithms that simulate natural handwriting and calligraphy, as well as tools for creating and editing strokes in web applications.

Applications include digital drawing apps, educational tools for teaching handwriting, and UI components for stroke-based input. Features commonly associated with jstrokes include dynamic stroke width based on velocity or simulated pressure, smoothing and resampling of input points, stylized rendering that imitates brush or pencil, and support for layered or composite strokes.

Implementation approaches typically rely on the Canvas 2D API or WebGL, often using Bezier curves to approximate stroke shapes. Key techniques include path construction from point samples, smoothing algorithms such as Catmull-Rom or Chaikin, velocity-based width calculation, and optional pressure emulation to mimic traditional media.

Performance considerations include minimizing redraws, batching updates, and using offscreen canvases. Compatibility with pointer events and touch input is standard, with fallbacks for mouse input.

In the broader ecosystem, several libraries and frameworks address similar goals, including Paper.js for vector graphics and Rough.js for sketch-like rendering. Jstrokes remains a conceptual category rather than a single canonical project, with multiple independent implementations.