Different objectfit strategies for rectangular regions preserving aspect ratio
npm install objectfitThis is a suite of functions for fitting (possibly overflowing depending on
the technique) one rectangular shape into another rectangular region,
preserving aspect ratio.

 
Displayed below is an example of drawing an image on a canvas using theobjectfit/contain function. It should be noted that as the functions
all use the same function signature, objectfit/cover could be used in
it's place.
``js
// examples/contain.js
const fit = require('../contain');
const crel = require('crel');
const img = crel('img', { src: 'http://upload.wikimedia.org/wikipedia/commons/thumb/4/46/Plasma_globe_60th.jpg/1024px-Plasma_globe_60th.jpg' });
const canvas = crel('canvas');
const css = require('fdom/css');
const context = canvas.getContext('2d');
// set document.body styling
[ ['margin', 0], ['overflow', 'hidden'] ].forEach(css(document.body));
function redraw() {
var bounds = fit(
[0, 0, window.innerWidth, window.innerHeight],
[0, 0, img.width, img.height]
);
canvas.width = window.innerWidth;
canvas.height = window.innerHeight;
context.drawImage.apply(context, [img].concat(bounds));
}
// redraw on image load and window resize
img.onload = redraw;
window.onresize = redraw;
document.body.appendChild(canvas);
`
All objectfit functions use the following function signature:
```
fit(container, => subject) => [x, y, width, height]
Use letterboxing or
pillarboxing) to resize
an object to fit within another containing rect, without affecting the
aspect ratio.
Ensure the subject completely fills the container leaving no whitespace
visible in the container.
Copyright (c) 2014, Damon Oehlman
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