iOS 9 and OSX El Capitan Issues

Hi all,

I'm running the developer betas for iOS 9 and OSX 10.11, and both platforms seem to have issues that break CesiumJS. I've got an app being built with Cesium and it works fine in iOS 8 and OSX 10.10 (Safari 8.06), but it gives a rendering error in Safari 8.1 and on iOS 9 mobile Safari and mobile Chrome. It does still work in desktop Chrome in OSX 10.11.


Can you post the exact errors you are seeing? Unfortunately, these are most likely bugs in Safari itself. Apple does not seem to care much about WebGL (or web standards in general). Safari can’t even run the WebGL conformance tests without crashing the entire browser (let alone pass them).

As for mobile Chrome, it’s actually just a wrapper around Safari because Apple doesn’t allow custom rendering engines on iOS. If it doesn’t work in Safari on iOS, it won’t work in Chrome or Firefox on iOS either (because it’s all using Safari under the hood).

I recommend anyone who wants to see Cesium (or WebGL in general) run better on iOS file bugs with Apple. If any of the examples no longer work in Safari, they might be more likely to fix those (since they are regressions).

Here’s the error. Also, I just checked some of the demos… and these do not work:

but… this does:


I can reproduce these errors using the Safari Nightly build (even on Yosemite). It looks like the problem is on their end and is related to our use of ALWAYS for depth testing in the SkyBox. I would file a bug with WebKit and Apple. You can use this link: which works in the official Safari but fails in Nightly versions. It will also provide extra debugging information about the failure for them.

I’ll file it later today. Thanks for your help.