Apple appears to be cracking down on the use of a hybrid graphics API which is a cross between Apple’s proprietary Metal and the open source Vulkan.
MoltenVK allows developers to use Vulkan in their programs, but the library then makes Metal API calls allowing the apps to run on iOS and macOS.
Apple has refused to update a game from an indie studio which uses MoltenVK.
MoltenVK 1.1.73 was being used without any modification. Had some tweaks been used, it would provide another potential reason for the refusal. As it stands, it seems Apple is simply not too happy with developers using MoltenVK.
The studio first published its game in May to the App Store, which Apple authorised despite the use of the MoltenVK API. The update, which was only a bug fix release, was rejected citing the use of a non-public API.
Modern graphics APIs have been prevalent in recent years with several notable releases including DirectX 12, Vulkan, Metal, and the now-defunct Mantle.
The reason for this recent prevalence is the emergence of multi-core systems and how older APIs were not optimised for them.
Some of the benefits have been impressive. A test of DOOM witnessed a performance improvement of 30 percent with the use of Vulkan over OpenGL.
You can find out more about MoltenVK here.
Do you think Apple should clamp down on the use of MoltenVK? Let us know in the comments.
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