WWDC2015 | My WWDC 2015 application

I am new to SceneKit, and I am trying to move nodes around the scene. How do I align a node to the node adjacent to it by making it 'snap into place'?

This is what it currently looks like when moving a node, it does not show ANY guide:

I do not want to manually change the values, as sometimes it shows multiple, as well as this being inconvenient and slow:

I can see there is an ability to make the node align (I assume using the keyboard or in some settings?) as seen on the WWDC 2015 Enhancements to SceneKit at 6m 20s.

Notice - it 'snaps' into place next to the other wooden box:

How am I able to achieve this? What other keyboard shortcuts/settings do I need to know? (I only know about the ⌥ (option) key which duplicates nodes)

Did Apple use some 3rd-party app?

If you have any questions, please ask!

Is there a way to get double-buffering at 120Hz (ProMotion) instead of triple buffering? I'm trying to minimize UI latency.

When I use Xcode's iOS Game template (which renders a rotating cube), I still get triple-buffering at 120hz, despite the trivial amount of work. It's double-buffered at 60hz.

To reproduce:

1. Create a new project in Xcode using File → New → Project
2. Select iOS → Game
3. Select Swift / Metal
4. In GameViewController add mtkView.preferredFramesPerSecond = 120
5. Product → Profile
6. Select Metal System Trace
7. Observe: triple buffering (3 colors for frames):

Looking at the graph, it seems the GPU finishes well within the time required for double-buffering.

Here's a useful video to watch for some background: https://developer.apple.com/videos/play/wwdc2015/233/

I was watching WWDC 2015 session 409 - Optimizing Swift Performance . It mentioned that Swift ensures array access happen in bounds. And Swift can lift checks out of loops. So that O(n) checks become O(1).

The example from the talk looks like this:

Ok I have a protocol called Environment

I'm attempting to configure a custom UIView in interface builder and get the view to render. Every time I attempt to do this with a custom Xib, I can get the xib to look fine in interface builder, but the moment I attempt to drop my MyCustomView into a UIVewController in interface builder, I get all sorts of compiler errors.

Every tutorial I've looked at goes something like this: "Just add @IBDesignable in front of your class declaration and put @IBInspectable in front of your vars and then watch the magic happen" (example: WWDC 2015 video). Or it's in Objective-C, or it's a 30 minute video in Aramaic with Chinese subtitles, etc.

My end objective is to be able to drag a UIView in, assign my custom class in identity inspector and have the contents of xib fill the UIView I dragged in and be able to tweak @IBInspectable properties.

Where I've looked for answers:

SO Post: @IBDesignable crashing agent

NS Hipster

A Medium Post

Errors I get:

Base.lproj/Main.storyboard: error: IB Designables: Failed to render and update auto layout status for PlaylistViewController (o1G-QR-OwX): The agent crashed

Base.lproj/Main.storyboard: error: IB Designables: Failed to update auto layout status: The agent crashed

Identity Inspector for my CurrentlyPlayingView:

Storyboard of my view after the I get the aforementioned errors:

The view that I'm trying to get to appear at the bottom of the above storyboard:

My code:

I recently got an iOS app rejected due to lack of IPv6 compatibility. After browsing the internet to investigate on the subject, I decided to view those two videos:

https://developer.apple.com/videos/play/wwdc2015/719/

https://developer.apple.com/videos/play/wwdc2016/714/

Now back to debugging the app, I am trying to follow what I can read here: http://www.brianjcoleman.com/tutorial-how-to-test-your-app-for-ipv6-compatibility/

At one point in the document we can read:

14. Once sharing is active, you should see a green status light and a label that says Internet Sharing: On. In the Wi-Fi menu, you will also see a small, faint arrow pointing up, indicating that Internet Sharing is enabled. You now have an IPv6 NAT64 network and can connect to it from other devices in order to test your app.

This is where I hit a problem. In my case I can indeed see:

"a green status light and a label that says Internet Sharing: On"

But I do not see in the Wi-Fi menu:

"a small, faint arrow pointing up, indicating that Internet Sharing is enabled".

So my guess is that I must have either done something the wrong way or have a configuration not matching what is expected by this document.

I have also tried several choice for Share your connection from: but to no avail. In the same way, looking at my iPhone does not show any sign of new access point.

Any suggestion coming from an expert on the subject or someone with some experience would be very much appreciated.

So I was watching a video from WWDC 2015, in which the presenter showcased a table view that has a fixed bar at the bottom, and he put a progress bar and some label in it. The video is about on-demand resources, so he didn't go into detail on how the bar is implemented. But I'm genuinely intrigued on how it's implemented:

The view's controller is a subclass of UITableViewController, so the root view of that controller must be a table view. As far as I know, there is no clean way to fix some UI view inside a table view.

It doesn't look like a toolbar from the navigation controller either, since the label is at the center and the progress bar is across the whole bar. I think you can only put discrete buttons inside the toolbar? Maybe that's not the case, but the from the size of that table view controller, it seems he didn't write much code to implement it.

I wonder how is this bottom bar implemented? You can see it at this moment of the video.

(I wonder if it's legal to paste a screenshot of WWDC video here?)

Reading from WWDC 2015 Session 720 it says:

Silent notifications are enabled by default. The user does not need to give permission to your app to use them. You can start using them without asking the user for permission

My question is:

1. How do you get the push token to use without registering for remotes?
2. If I still have to register, then what does "default" mean here?

Does it mean that you don't have to prompt to register, but still you have to register under the hood upon app launch? Which likely means default was a very bad word to choose?

I read this question but it doesn't answer this.

I've updated the Advanced NSOperations sample app to Swift 3. The only remaining build error is on this snippet of code from the DownloadEarthquakesOperation class.