Comment by drinchev | Hacker News Reader

Comment by drinchev | Hacker News Reader

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I wonder how they achieve "Zero lag". I've been using similar software ( AirDisplay [1] ) and the lagging is awful.

You have to be certified hardware manufacturer if you want to use the USB connection to transmit any data between the iPad and your Mac [2]. So my bet is they either use WiFi ( which can roughly get 60fps on retina resolution ) or Bluetooth 4. In both cases I think the refresh rate would not satisfy in a lot of cases, e.g. playing a YouTube video through their software on the iPad.

1: https://avatron.com/applications/air-display/ 2: https://avatron.com/support/faq-air-display/#toggle-id-13

EDIT:

I've found more information on their facebook page [3]

> To setup, download and open duet on your Mac (for free) and on iOS.

> Connect your device using a lightning or 30 pin cable. Done.

> No need to worry about firewall settings, Wi-Fi speed or your 802.11n network.

> Duet is secure, simple, and allows you to use your iOS and OS X devices in harmony.

So I guess I was wrong with my bets. Maybe they got a hardware manufacturer license from Apple. Anyway launch is on 16th, so let's see.

3: https://www.facebook.com/duetdisplay/info?tab=page_info

http://www.businessinsider.com.au/duet-display-app-turns-ipa...

Has a review

"Most importantly, Duet Display is the first app that actually turns your iPad into a second display I’d actually like to use. As someone who has tried Air Display and uninstalled it shortly afterward, frustrated, I can honestly say this is the only option that’s worth it."

Interesting, I tried Air Display and (another app) ages ago and used it off and on. It was "neat" and worked well as my Terminal window but a very poor stand for a monitor.

Looks like I'll be dusting off my iPad 2.

My guess would be they're just using the shared documents area .

There's a number of libraries on the desktop that let you access an API to write to the shared documents area. I'd guess they'd just be piping a mp4 feed to this and the iOS would just be reading from there.

> [...] shared documents area. I'd guess they'd just be piping a mp4 feed to this [...]

If this is the case I'd worry about the internal flash drive of the iPad. There must be a lot writes.

Is there any chance this approach could eventually be used on a Linux distro or Windows?

The technology already exists in X11. The problem is getting devices to act as display servers.

I haven't seen examples of folks trying to use iPads (for example) as X11 displays, likely because it's outside my area of expertise. Do you know of any examples?

iSSH includes an X11 display server, and I've had reasonable success using it with clients on an assortment of architectures, including a Tru64 VM running Open Genera. I wouldn't expect it to work well with something like video playback unless you've got a very fast and uncongested wireless network (or possibly a Lightning-to-Ethernet adapter, if such things exist), but if you don't need that kind of sustained responsiveness, it's at least worth a try.

I think the original product link isn't using wireless but instead depends on a wired connection. I've heard about using X11 over the internet but I'm worried that the lag would make this approach more annoying than effective.

It would be great to have a wired connection option on other operating systems besides the Mac.

Sounds like something that could only exist on Cydia. Has anyone checked there?

I do a lot of reading / annotating on my iPad. My other use case mostly involves emacs. I'd love to have a Linux matchstick dongle that I could simply plug in to my iPad to run emacs (and associated goodies like R, Python, etc).

https://news.ycombinator.com/item?id=8776877

There's a working download link in the footer, not sure why.

I downloaded the application, and it prompted a restart to install a driver, but did nothing further. duet.app does nothing when I open it, and plugging in my iPad does nothing either. Looks like we have to wait for the App Store release to install the iPad half of the app.

After installing, there is an icon in my menubar that says I should open duet on my iOS [1]. I believe we wait for the iOS app tomorrow and see what's the price and how this thing works

1: http://i.imgur.com/1fEHPLF.png

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