Liang-Barsky line clipping algorithm
npm install liang-barskyFast, _destructive_ implemetation of Liang-Barsky line clipping algorithm. It clips a 2D segment by a rectangle.
This is an adaptation of the C++ code
that impressed me by its simplicity.
Destructive
``js`
const a = [-10, -10],
b = [10, 10];
clip(a, b, [-5, -5, 5, 5]); // returns 1 - "clipped"
console.log(a); // [-5, -5]
console.log(b); // [5, 5]
Non-destructive
`js`
const a = [-10, -10],
b = [10, 10];
const an = a.slice(),
bn = b.slice();
clip(a, b, [-5, -5, 5, 5], an, bn); // returns 1 - "clipped"
console.log(an); // [-5, -5]
console.log(bn); // [5, 5]
console.log(a); // [-10, -10]
console.log(b); // [10, 10]
Return value is 1 if the line was clipped, and 0 if it lies completely
outside of the provided bounding box.
`
npm install -S liang-barsky
`js`
import { clip } from 'liang-barsky';
// or
var clip = require('liang-barsky');
Or just drop-in the file
`html`
I ran a check against the Cohen-Sutherland algorithm implemented by @mourner
for clipping just one segment. Though test include memory allocation, they are
fair for the task at hand, since you can use the results in an equal manner after
the invocation of the clipper.
`
npm run benchmark
`
liang-barsky x 112,058,856 ops/sec ±6.46% (87 runs sampled)
mapbox/lineclip x 27,754,592 ops/sec ±1.94% (98 runs sampled)
- Fastest is liang-barsky
Implement a sub-routine for polylines. Loop through pairs, tracking in-out
transitions.
MIT