Hacker News Reader

Comment by dminor | Hacker News Reader

> when someone visits the site, imgix will deliver the appropriate photos and, in need be, reformat or resize them. If someone visit your site with an Apple iPad, the service can instantly reformat an image for the tablet’s “Retina” display.

I didn't see any documentation about this on their site. Can they deliver, via a single URL, differently sized images for mobile vs desktop? This is one of the biggest headaches when trying to do responsive design.

View on HN

We have a service similar to imgix (thumbr.it). The way we serve retina images is that you add @2x to the name of the images with JS, and when we see the image name ends with @2x we serve double the size you requested (see http://thumbr.it/api/documentation/#retina).

I guess the imgix guys do something similar.

Serving different images with exactly the same URL is tricky because it will confuse the cache.

Stupid question: are you just doubling every pixel of a non-retina source for the @2x images? Does that really provide any extra clarity on a Retina display (beyond setting the proper size of the image?) Or are you actually starting with an @2x image and halving it for non-2x default?

The retina modifier is only useful when you request a smaller thumbnail than the original.

So your original may be 1000x1000px, you use a 128x128 thumbnail on your regular (non-retina) site, and you serve 256x256 thumbnail to your retina users.

If your original image is small then there is nothing to do.

Reply on news.ycombinator.com