#  [](https://www.npmjs.com/package/@thi.ng/geom-clip-line)  [](https://mastodon.thi.ng/@toxi) > [!NOTE] > This is one of 214 standalone projects, maintained as part > of the [@thi.ng/umbrella](https://codeberg.org/thi.ng/umbrella/) ecosystem > and anti-framework. > > 🚀 Please help me to work full-time on these projects by [sponsoring > me](https://codeberg.org/thi.ng/umbrella/src/branch/develop/CONTRIBUTING.md#donations). > Thank you! ❤️ - [About](#about) - [Status](#status) - [Related packages](#related-packages) - [Installation](#installation) - [Dependencies](#dependencies) - [API](#api) - [Authors](#authors) - [License](#license) ## About 2D line clipping (Liang-Barsky). This is a support package for [@thi.ng/geom](https://codeberg.org/thi.ng/umbrella/src/branch/develop/packages/geom). Current implementation is partially based on [toxiclibs](http://toxiclibs.org) (Java) and Clojure version [thi.ng/geom-clj](http://thi.ng/geom-clj). Also see [@thi.ng/geom-clip-poly](https://codeberg.org/thi.ng/umbrella/src/branch/develop/packages/geom-clip-poly) sister package. The following main functions are provided: - [`clipLinePoly()`](https://docs.thi.ng/umbrella/geom-clip-line/functions/clipLinePoly.html) - [`clipLineSegmentPoly()`](https://docs.thi.ng/umbrella/geom-clip-line/functions/clipLineSegmentPoly.html) - [`clipPolylinePoly()`](https://docs.thi.ng/umbrella/geom-clip-line/functions/clipPolylinePoly.html) - [`liangBarsky2()`](https://docs.thi.ng/umbrella/geom-clip-line/functions/liangBarsky2.html) ## Status **STABLE** - used in production [Search or submit any issues for this package](https://codeberg.org/thi.ng/umbrella/issues?q=%5Bgeom-clip-line%5D) ## Related packages - [@thi.ng/geom-clip-poly](https://codeberg.org/thi.ng/umbrella/src/branch/develop/packages/geom-clip-poly) - 2D polygon clipping / offsetting (Sutherland-Hodgeman, Grainer-Hormann) ## Installation ```bash yarn add @thi.ng/geom-clip-line ``` ESM import: ```ts import * as gcl from "@thi.ng/geom-clip-line"; ``` Browser ESM import: ```html ``` [JSDelivr documentation](https://www.jsdelivr.com/) For Node.js REPL: ```js const gcl = await import("@thi.ng/geom-clip-line"); ``` Package sizes (brotli'd, pre-treeshake): ESM: 762 bytes ## Dependencies - [@thi.ng/api](https://codeberg.org/thi.ng/umbrella/src/branch/develop/packages/api) - [@thi.ng/geom-isec](https://codeberg.org/thi.ng/umbrella/src/branch/develop/packages/geom-isec) - [@thi.ng/vectors](https://codeberg.org/thi.ng/umbrella/src/branch/develop/packages/vectors) Note: @thi.ng/api is in _most_ cases a type-only import (not used at runtime) ## API [Generated API docs](https://docs.thi.ng/umbrella/geom-clip-line/) ```ts import { clipPolylinePoly, liangBarsky2 } from "@thi.ng/geom-clip-line"; clipPolylinePoly( // polyline vertices [[10, -50], [30, 30], [-50, 50], [150, 50], [70, 70], [90, 150]], // boundary polygon vertices [[0, 0], [100, 0], [100, 100], [0, 100]] ); // result is 3 polylines: // (since the original is temporarily leaving the poly) // [ // [ [ 22.5, 0 ], [ 30, 30 ], [ 0, 37.5 ] ], // [ [ 0, 50 ], [ 100, 50 ] ], // [ [ 100, 62.5 ], [ 70, 70 ], [ 77.5, 100 ] ] // ] // Liang-Barsky is optimized for rectangular clipping regions liangBarsky2( // line end points [-10, -20], [30, 400], // min/max clip rect [0, 0], [100, 200] ) // [ [ 0, 85 ], [ 10.952380952380953, 200 ], 0.25, 0.5238095238095238 ] // returns undefined if line is completely outside the clip rect liangBarsky2( // line end points [-10, -20], [-30, 400], // min/max bbox [0, 0], [100, 200] ) // undefined ``` ## Authors - [Karsten Schmidt](https://thi.ng) If this project contributes to an academic publication, please cite it as: ```bibtex @misc{thing-geom-clip-line, title = "@thi.ng/geom-clip-line", author = "Karsten Schmidt", note = "https://thi.ng/geom-clip-line", year = 2013 } ``` ## License © 2013 - 2026 Karsten Schmidt // Apache License 2.0