3 ms·
It says specifically for maps rendering. Keep in mind the original Apple Watch had a 520 mhz single core processor and 256 MB of RAM shared with the OS and anyt
by wlesieutre 5y ago
It says specifically for maps rendering. Keep in mind the original Apple Watch had a 520 mhz single core processor and 256 MB of RAM shared with the OS and anything else running in the background. And pre-SwiftUI, 3rd party developers were working with WatchKit which was a lot more limited than what Apple was using internally.
Could that render a single map frame? Probably. But if this was an animated map showing the car location with zoom/pan to follow along, I can definitely see it making sense to offload to the phone.
What surprises me is that they needed a private entitlement for this, since you should be able to render a view out to an image without any entitlements [1]. Maybe that solution doesn't work offscreen? Or if the map was animated, maybe this can't play smoothly enough?
[1] https://stackoverflow.com/questions/30696307/how-to-convert-a-uiview-to-an-image https://stackoverflow.com/questions/30696307/how-to-convert-...
- wlesieutre 5y agoMore info on WatchKit, per [1] > Can I use custom views in the Apple Watch? Can I customize the interface elements beyond their public API? > No. You can’t use custom views. WatchKit only supports certain native interface elements. None of the interface elements can be subclassed or customized beyond their public API. The available interface elements are WKInterfaceLabel, WKInterfaceButton, WKInterfaceImage, WKInterfaceGroup, WKInterfaceSeparator, WKInterfaceTable, WKInterfaceSwitch, WKInterfaceMap, WKInterfaceSlider and WKInterfaceTimer. In the original watchOS release, you can't even draw shapes, only display images. So to make a custom map you'd have to render the image yourself for display as a WKInterfaceImage. With watchOS 2 you were able to draw to a WKInterfaceImage with Core Graphics [2], but Uber had written their app before this. [1] https://www.raywenderlich.com/1950-watchkit-faq https://www.raywenderlich.com/1950-watchkit-faq [2] https://github.com/shu223/watchOS-2-Sampler#draw-paths-updated-by-hoppenichu https://github.com/shu223/watchOS-2-Sampler#draw-paths-updat...
- lallysingh 5y agoYeah that's the part that seems off. It implies that the image for the watch was on the iphone screen first, which doesn't seem quite "professional quality". Did they render something high quality (to look good on three options) with the GPU and then subsample the image for the watch?