Function scaleFromMidpoint

Scales a line from its midpoint

Example: Shorten by 50%, anchored at the midpoint

import { Lines } from 'https://unpkg.com/ixfx/dist/geometry.js'
const l = {
 a: {x:50, y:50}, b: {x: 100, y: 90}
}
const l2 = Lines.scaleFromMidpoint(l, 0.5);

scaleFromMidpoint(line, factor): Line
Parameters
- line: Line
- factor: number
Returns Line