Hacker News Reader

Comment by DavideNL | Hacker News Reader

Apple decided Sidecar (an iPad as second screen) isn't available on my Macbook Pro 2015 in macOS Catalina;

Luckily i found http://dev.zeppel.eu/luca/SidecarCorePatch which patches the SidecarCore framework and now it runs just fine.

View on HN

The CPU in your machine probably doesn’t support native video encoding extensions, thus taking a massive performance hit encoding the video stream for Sidecar. I believe that’s why Apple did this.

Happy to be corrected on this, by the way.

No you're 100% right.

Only the 2016+ generation of Macs support hardware accelerated HEVC encoding/decoding.

My guess is that OP's computer would struggle to use Sidecar with an app like Photoshop (a primary use case for this feature).

That might be true indeed, i have not tested any heavy/graphic editing apps like Photoshop. Also i'm using the smaller 10'5 iPad pro, not the 12'9.

Playing a 1920x1080 video (6000 Kbps) works just fine, super smooth and no cpu spikes or whatever. However i just noticed when using the default Catalina wallpaper on the Desktop the iPad screen starts flickering. Weird.

Ah, I wonder if this is why Google Hangouts is so awful on my 2015 MBP.

Google Hangouts is awful on most devices, while webrtc demo apps work fine

In fairness, they "obsoleted" machines whose CPUs didn't have the features to support a good experience with Sidecar[1]. I wanted to wait until the 16" MBP rolled out before replacing my 2015, but I opted to go with a 2019 and couldn't be happier.

[1]: http://dev.zeppel.eu/luca/SidecarCorePatch/issues/29#issueco...

Yeah, that seemed a bit odd to me. Maybe there's some sort of non-obvious hardware dependency. (There is admittedly one issue I've found with Catalina related to Captive Portal which has a workaround but I can at least believe has a hardware component.) But it certainly wasn't clear why the cutoff.

The old hardware lacks the required video encoders.

My guess is that iPads only have the hardware decoders for format X so that’s what you have to produce, then if the host machine lacks hardware encoders you break the “second monitor” feature - eg bad performance: lagging/dropped frames would break video, etc

Reply on news.ycombinator.com